PROTEIN: All of Your Burning
Questions Answered
By Alan Aragon
- FIRST EDITION Copyright: ©2021 By Alan Aragon
All rights reserved. This book or any part thereof, may not be
reproduced or recorded in any form without permission in writing
from the author, except for the quotation of brief excerpts, to
which proper attribution is given.
Suggested citation:
Aragon AA. Protein: All of Your Burning Questions Answered. 1st ed., Los
Angeles: Alan Aragon. https://alanaragon.com/books
Cover art by Jeana Aragon (@jeana.aragon on Instagram)
This book is NOT intended for the treatment or prevention of disease, nor
as a substitute for medical treatment, nor as an alternative to medical
advice. It is a review of scientific literature presented for informational
purposes, to increase public knowledge of the developments in the field of
nutrition. The information herein should not be adopted without
consulting your doctor or qualified healthcare professional. Use of the
information herein is at the sole choice and risk of the reader. The author
and publisher specifically disclaim all responsibility for any liability, loss, or
risk (personal or otherwise) incurred as a direct or indirect consequence of
the application of any of the contents of this book.
-1-
This book is dedicated to Jeana, Lex, and Max.
You are my dream team and my life’s joy.
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Contents
Chapter 1: Hierarchy of importance (start here, then skip through
the book as you wish) [5]
Chapter 2: How much protein does the general public habitually
consume? [8]
Chapter 3: How much protein is needed to maintain health in the
general population? [10]
Chapter 4: How much protein do competitive athletes habitually
consume? [13]
Chapter 5: How much protein maximizes athletic performance?
[16]
Chapter 6: How much protein maximizes muscle gain? [18]
Chapter 7: How should protein be distributed through the day to
maximize muscle gain? [24]
Chapter 8: How much protein maximally preserves muscle while
losing fat? [27]
Chapter 9: How should protein be distributed through the day to
maximize muscle retention while dieting? [30]
Chapter 10: How does protein intake influence recomposition?
[36]
Chapter 11: How does protein timing (pre, during, and postexercise) impact athletic performance? [39]
Chapter 12: How does protein timing (pre, during, and postexercise) impact body composition? [43]
Chapter 13: How does BCAA supplementation affect body
composition? [49]
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Chapter 14: How does a high protein intake impact ketosis? [53]
Chapter 15: How does protein restriction influence longevity?
[56]
Chapter 16: How does advanced age impact protein utilization
and dosing requirements? [62]
Chapter 17: How much protein do adolescents need? [67]
Chapter 18: How do sex differences influence protein
requirements? [69]
Chapter 19: How do high-protein diets impact bone and kidney
health? [73]
Chapter 20: Is there an inherent advantage to pre-bed casein?
[76]
Chapter 21: How does postworkout whey compare to chicken,
beef, or casein for improving body composition & strength? [79]
Chapter 22: How do whole eggs compare with egg whites for
muscle growth? [82]
Chapter 23: If collagen is considered a low-quality protein, does
that make collagen supplements useless? [85]
Chapter 24: How do plant proteins compare to animal proteins
for muscle growth? [87]
Chapter 25: How satiating is protein, really? [92]
Chapter 26: What about non-linear protein intake through the
week (training days vs non-training days, protein hyperfeeds)?
[95]
Chapter 27: Protein servings & sources [101]
Postscript [108]
References [109]
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Chapter 1: Hierarchy of importance (start here,
then skip through the book as you wish)
Welcome!
Welcome, and thank you for cracking open this little beast. In
the odd case that you’re reading this, yet you don’t know who I
am or why I’m worth listening to, here is my bio, and here are
my peer reviewed publications. The content of this book is
meticulously compiled from the current state of the scientific
evidence combined with nearly three decades of field
experience. I’m proud to say that I’ve co-authored several of the
key research publications that have shaped the current
practice guidelines on protein intake for sports and fitnessoriented populations.
The aim of this book is to provide a highly focused, fluff-free
resource that concisely answers the most frequently asked
protein questions I’ve encountered throughout my career as a
trainer, nutritional counselor, researcher, and educator. So yes,
get excited. Get very excited. :)
Hierarchy of importance
Here’s the crux of why I wanted you to read this introductory
section first. Without maintaining the proper big-picture
-5-
perspective, the smaller details will lack meaning and context.
As you go through the material, keep in mind that there’s an
underlying order of importance when it comes to the various
aspects about protein. From most to least important, the
ranking is as follows (keep in mind that these are specific to
protein; this hierarchy does not apply to all nutrients):
1) Total daily protein amount. For most of you reading this,
getting total daily amount right is the most influential factor.
Still, for a minority of individuals with very limited options,
it’s theoretically possible to get total daily intake right, but
lack quality (sufficient essential amino acids within
bioavailable contexts1). We’ll be operating under the
assumption that quality of the dietary protein sources is high
overall. Therefore, from a practical standpoint, total daily
amount is king.
2) Distribution of protein through the day – in other words, the
spread or pattern of intake, including number of feedings
and protein dose per meal. The impact of a more evenly
spread versus skewed pattern, or a low vs. high feeding
frequency, or a narrow versus broad feeding window
depends on the individual goal. Nevertheless, these aspects
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of within-day distribution are of distantly secondary
importance compared to total daily amount.
3) Timing of protein relative to the training bout. For most
goals, this factor has the least impact, especially in the
context of programs with typical protein feeding
distributions amounting to the proper daily total. Exceptions
where protein timing relative to the training bout warrants
attention are programs with very low meal frequency (e.g.,
1-2 meals per day). In the latter case, the positioning/timing
of protein can potentially influence rates of progress. The
finer details of these concepts are elucidated in subsequent
chapters.
Caveats
Keep in mind that nutritional needs vary across the stages of
the human life cycle, well as different disease states. The
protein requirements discussed in this book apply to healthy
adults, unless specified otherwise.
With that out of the way, let’s dive in!
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Chapter 2: How much protein does the general
public habitually consume?
A common statement made by professors throughout my
college experience was that protein supplements (and the push
for greater protein intakes in fitness-related media) are a scam
because people already consume more than enough protein. A
more nuanced approach to this topic shows that different goals
warrant different protein intakes. So, this claim always set off
my skepticism sensors.
The latest protein consumption data from the National Health
and Nutrition Examination Survey (NHANES)2 shows that men
aged 19-50 years consume 101.2-109.5 g/day. Using NHANES
data, the Centers for Disease Control and Prevention (CDC)
reported that the average bodyweight of men in the US is 89.8
kg.3 This amounts to an average protein intake of
approximately 1.17 g/kg in men. NHANES data for women aged
19-50 years showed an intake of 70.3-72.9 g/day.2 The CDC
reported an average bodyweight of 77.4 kg.3 This works out to
a protein intake of approximately 0.92 g/kg in women.
Both of these protein intakes (1.17 & 0.92 g/kg in men &
women, respectively) exceed the Recommended Daily
-8-
Allowance (RDA) for protein, which is 0.8 g/kg.4 So, by that
standard, my professors were correct. The general public’s
protein intake exceeds the “official” public health guideline.
The problem is that the RDA is insufficient to meet the needs of
a substantial proportion of the general population, and it comes
up short for practically all dieting and athletic populations. The
following chapters cover the RDA’s shortcomings in more
detail.
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Chapter 3: How much protein is needed to maintain
health in the general population?
Ancient & tenacious
The Recommended Daily Allowance (RDA) for protein is 0.8
g/kg.4 Notably, this figure was derived from nitrogen balance
studies on sedentary individuals. It formally became part of the
public health guidelines in 1980. It’s now 2021, and the RDA for
protein hasn’t changed; no adjustments for athletes or
physically active individuals, no increase for the elderly. Forty
years is a long time for a guideline as important as protein
intake to be outdated, despite a mountain of research showing
benefits of greater intakes across virtually all populations. But,
this is pretty much the normal (glacial) pace of conventional
wisdom when it comes to altering established nutrition rules in
general.
Moving forward
The research community’s call to re-evaluate the RDA has been
ongoing and vigorous. A memorable 2009 review by Donald
Layman,5 one of the pioneers of protein research in physically
active subjects, was blatantly titled, Dietary Guidelines should
reflect new understandings about adult protein needs. This was
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perhaps the first paper to address the RDA’s lack of
contingencies for protein needs based on the state of energy
balance. Layman accurately contended that protein
requirements are inversely proportional to energy intake. In
other words, protein requirements increase in the face of
hypocaloric (energy deficit) conditions, which pose an inherent
threat to lean mass preservation. Furthermore, Layman noted
beneficial effects on calcium metabolism and bone health at
protein intakes above 1.2 g/kg.
Protein requirements for the general adult population are
largely focused on preserving lean mass in compromising
conditions such as dieting and aging (separate goals from
getting jacked or enhancing athletic performance, covered
elsewhere in this book). A review by Lonnie et al6 relayed the
collective guidelines of the International PROT-AGE Study
Group and European Society for Clinical Nutrition and
Metabolism (ESPEN) for individuals over age 65, which are as
follows: 1.0-1.2 g/kg for healthy folks, 1.2-1.5 g/kg for those
with acute or chronic illnesses, and 2.0 g/kg for those with
severe illnesses, injuries, or malnutrition.
A review by Phillips et al7 took direct aim at the RDA, focusing
on protein needs for optimizing health and longevity, arriving
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at a recommendation of 1.2-1.6 g/kg. This recommendation
was inclusive of the general adult population, from younger to
older. On the more generous end, Pencharz et al8 proposed an
intake of 1.5-2.2 g/kg. Interestingly this recommendation
pertained to the general population (not strength athletes or
bodybuilders). However, their reasoning for this range was
based, in part, on the Institute of Medicine’s Acceptable Daily
Macronutrient Range (ADMR) of 10-35% of total energy
intake,9 which carries a high degree of subjectivity.
As is typical in research, the recommendations vary according
to different perspectives and interpretations of the data.
Among these recommendations, the intake range best
supported by the research evidence for the healthy, notnecessarily-athletic-nor-dieting general public is Phillips et al’s
proposed guideline of 1.2-1.6 g/kg.7 In Imperial terms, this
translates to 0.54-0.72 g/lb.
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Chapter 4: How much protein do high-level
competitive athletes habitually consume?
Strength/power athletes
Gillen et al10 reported that elite-level Dutch strength athletes
(71 subjects) had a protein intake that averaged 1.8 g/kg in
those who used protein supplements, and 1.5 g/kg in those
who did not. Slater and Phillips10 relayed the reported intakes
of various strength/power athletes at the elite, national, and
international levels as follows:
Throwing:
Sprinting:
Weightlifting:
Men
1.3-2.4 g/kg
1.5 g/kg
1.3-3.2 g/kg
Women
1.1-2.5 g/kg
1.7 g/kg
[no data]
Bodybuilders
Slater and Phillips11 reported that the protein intakes of elitelevel male and female bodybuilders was 1.7-2.4 g/kg & 1.5-2.0
g/kg, respectively. A systematic review by Spendlove et al12
reported a range of 157 g/day (1.9 g/kg/day) to 406 g/day (4.3
g/kg/day) among a mix of drug-free and enhanced competitive
bodybuilders. Chappell et al13 reported that in high-level drugfree bodybuilders, pre-contest protein intakes of men and
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women who placed in the top-5 were 3.3 & 2.8 g/kg,
respectively. Protein intake of men and women who placed out
of the top-5 were 2.7 & 2.9 g/kg, respectively. Body
composition was not reported in this study, so no intakes based
on fat-free mass can be reported.
Mixed/team sports
Team sports fall somewhere in the middle of the strengthendurance continuum, with a mix of demands and energy
system contributions on that continuum. In a large sample of
elite-level team sport athletes (242 subjects), Gillen et al10
found that protein intake averaged 1.6 g/kg in subjects who
used protein supplements, and 1.4 g/kg in those who did not. A
systematic review by Jenner et al14 reported the intakes of
various professional & semi-professional mixed/team sports
athletes as follows:
Football (soccer):
Australian football:
Rugby union:
Wheelchair basketball:
Volleyball:
Ice hockey:
Men
1.9-2.0 g/kg
1.8-3.4 g/kg
2.2-2.7 g/kg
1.7 g/kg
[no data]
[no data]
Women
[no data]
[no data]
[no data]
[no data]
0.9 g/kg
1.4 g/kg
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Endurance athletes
Finally, we have our quirky friends who just love to see how far
they can push the limits of their fuel tanks. A classic review by
Tarnopolsky et al15 reported protein intakes ranging 1.0-2.2
g/kg among high-level male and female endurance athletes.
More recently, Burke et al16 reported that in elite-level
Australian endurance athletes (4 canoeists, 2 cyclists, 11
distance runners, 3 kayakers, 9 rowers, 9 swimmers, and 3
walkers), protein intake averaged 1.9 g/kg.
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Chapter 5: How much protein maximizes
athletic performance?
The following table outlines the latest position stands of the
major nutrition (& exercise) organizations on protein
requirements for athletic populations. The protein
recommendation of the ISSN17 has been the same since their
initial position stand on this topic in 2007; they were a bit
ahead of the game. The current recommendation of the
Academy of Nutrition and Dietetics, Dietitians of Canada, and
American College of Sports Medicine18 has been increased
since their previous statement in 2009, where the range was
1.2-1.7 g/kg.
POSITION STANDS ON PROTEIN INTAKE FOR ATHLETIC GOALS
Publication
Population
Recommendation
Jäger R, et al. International
Society of Sports Nutrition
Position Stand: protein and
exercise. J Int Soc Sports
Nutr. 2017 Jun 20;14:20.
[PubMed]
Physically active individuals,
including competitive and
recreational athletes aiming
to enhance muscular
strength, endurance, or size
1.4-2.0 g/kg
Thomas DT, et al. Position
of the AND, DC, & ACSM:
Nutrition and Athletic
Performance. J Acad Nutr
Diet. 2016 Mar;116(3):501528. [PubMed]
Competitive athletes in a
range of sports spanning the
“Higher intakes may be
strength-endurance
indicated for short periods
continuum
during intensified training
or when reducing energy
intake.”
“Higher protein intakes
(2.3-3.1 g/kg/d) may be
needed to maximize the
retention of lean body
mass in resistance-trained
subjects during hypocaloric
periods.”
1.2-2.0 g/kg
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Caveats to accepting the position stands as gospel
Although the position stands of the above organizations
represent the weight of the evidence, this doesn’t mean that
they are indisputable. The indicator amino acid oxidation
(IAAO) technique is a validated method used for determining
indispensable amino acids in humans.19 Recent studies using
the IAAO technique have shown protein requirements greater
than the low-end of the protein ranges listed in the position
stands. Kato et al20 found that in endurance athletes on a
training day had an estimated average requirement of 1.65
g/kg. More recently, Bandegan et al21 reported that the
estimated average protein requirement in endurance-trained
subjects in the 24-hour post-trained period was 2.1 g/kg.
The latter findings call into question the recommendations of
the current position stands on protein intakes for athletes,
especially the allowance of intakes as low as 1.2-1.4 g/kg.
Based on the current evidence, I would not recommend dipping
below 1.6 g/kg for competitive athletes, or recreational
athletes who take winning seriously.
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Chapter 6: How much protein maximizes muscle
gain?
Let’s talk about growth for a moment
Alright, so what about protein needs for muscle growth? This
question is not all that simple. For maximizing muscle growth
(also called muscle anabolism or hypertrophy), even the most
carefully optimized protein intake is just part of the picture. In
order to prime the physiological environment for growth,
hypercaloric conditions (a caloric surplus) must be sustained.
While muscle growth is indeed possible in caloric maintenance
and deficit conditions, growth cannot be maximized unless a
surplus of energy is consumed.
Hypocaloric conditions compromise nutrient & energy
availability. This suppresses anabolic signaling and muscle
protein synthesis (MPS), ultimately compromising the rate of
muscle growth. Hypocaloric conditions can tip the balance of
turnover toward muscle protein breakdown (MPB). In
contrast, hypercaloric conditions facilitate the opposite.
Sustaining a caloric surplus drives muscle growth by not only
increasing anabolic signaling and MPS, but also supporting the
escalating demands of progressive resistance training volume.
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Just what kind of caloric surplus is needed, you ask? The
answer is, it depends on the population. Beginners and more
advanced trainees have different requirements. The following
table is a summary of the energy surplus guidelines from a
recent paper I co-authored with Brad Schoenfeld:22
CALORIC SURPLUS GUIDELINE SUMMARY
Population/training Magnitude of
Nature of the surplus
status
the surplus
Untrained/novice
Approximately
Greater potential benefit of a
or deconditioned
20-40% above
predominance of carbohydrate due to
maintenance
higher total energy surplus capacity.
needs (~500Surplus should include a minimum
1000 kcal)
protein dose of approximately 20-40 g (or
at least ~0.4 g/kg of total bodyweight).
Trained/more
Approximately
advanced; closer to 10-20% above
maximum potential maintenance
needs (~250-500
kcal)
Lesser potential benefit of carbohydrate
predominance due to lower total energy
surplus capacity. Surplus should include a
minimum protein dose of approximately
20-40 g (or at least ~0.4 g/kg of total
bodyweight).
Notes & caveats
First and foremost, a caloric surplus for muscle gain must be built upon a
foundation of sufficient total daily protein and energy intake. In general, for
optimizing high-intensity fueling requirements of progressive resistance training,
an energy surplus should focus on increasing carbohydrate. However, increased
proportions of protein can be employed depending on how cautiously one wants
to court the potential for concurrent fat gain. More advanced trainees closer to
their potential have less room for surplus energy partitioning into lean tissue, and
thus may choose to employ protein-focused surpluses. Regardless of training
status, individuals cautiously avoiding fat gain might also benefit from this tactic.
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Important side-note: a common misconception is that since
resting muscle burns about 13 kcal/kg (6 kcal/lb) per day,23
only a tiny surplus is required to build muscle. Under that
presumption, the surpluses in the above table might seem too
large. However, aside from the research evidence showing
otherwise,22 I would encourage you to head over to the July
2020 issue of AARR, and read the article titled, A pound of
muscle burns [X] calories per day: facts, fallacies, & applications.
In that article, I discuss the various components of energy
expenditure increases involved with the process of building
new muscle tissue. The resting value of 13 kcal/kg does not
account for non-exercise & exercise activity increases, and thus
should not be used for programming caloric surpluses for
muscle growth.
So, assuming we’ve got the right caloric surplus in place,
maximizing muscle growth can be achieved with 1.6-2.2 g/kg
(0.7-1.0 g/lb). This range is derived from Morton et al,24 who
conducted the largest meta-analysis to date on the effect of
protein supplementation on resistance training-induced gains
in muscle mass and strength. I was fortunate enough to be one
of the collaborators in this paper. Here’s a key passage from the
discussion section which I snipped for brevity:
“Here we provide significant insight by reporting an unadjusted
plateau in RET-induced gains in FFM at 1.62 g protein/kg/day
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(95% CI: 1.03 to 2.20). […] Given that the confidence interval of
this estimate spanned from 1.03 to 2.20, it may be prudent to
recommend ~2.2 g protein/kg/d for those seeking to maximise
resistance training-induced gains in FFM.”
With all this said, there are a few caveats to consider before
taking the results as unassailable gospel. Note that this analysis
excluded trials involving hypocaloric conditions, which have
their own protein requirements (discussed in Chapter 8). It
also did not focus specifically on highly trained, athletic, or
competitive populations – let alone advanced trainees on
ergogenic supplementation and/or drugs. Furthermore,
protein needs based on total body mass are presumptive about
body composition, when clearly there’s wide variability in the
proportions of lean mass and fat mass between individuals.
Nevertheless, Morton et al’s findings were echoed in
subsequent research by Bandegan et al,25 who found a protein
requirement of 1.7-2.2 g/kg in bodybuilders on a non-training
day, using the indicator amino acid oxidation (IAAO) technique.
Using the same method, Mazzulla et al26 reported that
resistance-trained men required 2.01-2.38 g/kg.
Current bodyweight vs. target bodyweight vs. lean mass
Protein requirements based on total bodyweight predominate
the peer reviewed literature; it’s actually quite rare to find
- 21 -
publications that issue recommendations based on lean mass
(typically denoted as fat-free mass or FFM). Total bodyweightbased protein recommendations are typically issued under the
presumption of normal-weight individuals. The pitfall here is
that it’s possible to overshoot or undershoot estimated needs if
someone is highly over- or underweight.
A simple solution to this, which also circumvents the need to
estimate body composition, is to base protein intake on goal
bodyweight or target bodyweight. Use your current weight to
estimate protein needs if you’re seeking to maintain current
weight. Otherwise, base your estimations on target
bodyweight. This is an effective way of approximating lean
mass, with a built-in margin of safety.
A quick-and-dirty estimate of protein needs that doesn’t factor
bodyweight into the calculation is basing your protein gram
target on your height in centimeters (multiply inches by 2.54).
If you run the numbers on this, you’ll find that it’s in the right
ballpark for taller folks, but shoots high for shorter individuals.
As such, it tends to overestimate the protein needs of women
who are not particularly tall.
For those who are hell-bent on basing protein intake on lean
mass or fat-free mass (FFM), a reasonable range for
maximizing muscle growth is 1.8-2.6 g/kg FFM. This range is
- 22 -
derived from IAAO data in recent studies I discussed in the
October 2019 issue of AARR. To simplify things, a target of 2.2
g/kg FFM (1.0 g/lb FFM) shoots right in the middle of the
‘optimal’ range. This is a safe baseline target for the goal of
muscle gain. Like any programming variable, this would need
to be put to trial and adjusted as needed.
Summing up
• Maximizing muscle growth requires a sustained caloric
surplus (muscle growth can still occur without a surplus, it
just won’t be maximized).
• Based on the collective longitudinal research that directly
assessed body composition, total daily protein intake for
maximizing muscle gain is 1.6-2.2 g/kg of total bodyweight
(0.7-1.0 g/lb).24
• Women typically carry significantly more body fat than
men, so shooting lower on this range might be more
appropriate as a starting point from which to adjust
according to results.
• Remember to use target bodyweight if you’re highly overor underweight.
• Alternatively, 2.2 g/kg FFM (1.0 g/lb FFM) can be put to
trial and adjusted according to individual response.
- 23 -
Chapter 7: How should protein be distributed
through the day to maximize muscle gain?
For gaining muscle, distribution (pattern, frequency, or spread)
of protein doses through the course of the day appears to
matter, especially if the goal is to maximize muscle growth. To
the best of our knowledge, pushing maximal growth is best
accomplished by having protein in similar doses through the
course of the day,27 from waking to pre-bed.28 Each dose should
maximally stimulate muscle protein synthesis (MPS). Muscle
protein breakdown (MPB) is the other side of protein turnover.
Maxing-out MPS (as opposed to minimizing MPB) is the more
important target since changes in MPS are 4-5 times greater
than MPB in response to exercise and feeding..29 Both
processes occur in constant, dynamic cycles. Muscle growth
occurs as a result of MPS exceeding MPB over time.
Recent research has refuted the longstanding presumption that
20-25 g high-quality protein (containing >2 g leucine) elicits a
maximal anabolic response. Macnaughton et al30 reported
greater MPS with 40 vs 20 g whey after a high-volume
resistance training session, and Park et al31 reported greater
MPS with 70 vs 35 g beef protein within a mixed macronutrient
meal. Collectively, the current evidence suggests a minimum of
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4 feedings dosed at approximately 0.4-0.55 g/kg per meal (the
full text detailing the rationale of this distribution is available
here).32 Now, is it possible that muscle growth can be
maximized with a lower number of feedings than 4 per day, or
a more skewed/less even distribution of meals? Yes, it’s
possible. That’s one of the gray areas of research with room for
more investigation. I would even speculate that 3 protein
feedings per day versus 4 (or more) is not likely to be
meaningful outside of competitive conditions where very small
differences can determine different placings. However, I would
also speculate that less than 3 protein feedings per day is not
likely to maximize hypertrophy from a practical standpoint
(gastrointestinal issues associated with huge meals), as well as
a mechanistic standpoint (the anabolic “ceiling” seen in the
limited MPS elevations per feeding).
I’ll reiterate that muscle growth is possible with low feeding
frequencies, including purposely narrowed feeding windows.
However, merely achieving some degree of muscle growth is a
distinctly different goal from maximizing rates of muscle
growth. Protein feeding frequency & distribution will remain
an area of controversy as long as there’s a lack of direct
comparisons of different meal frequencies in resistance
trainees in trials that measure body composition changes over
- 25 -
time. In the meantime, the following table provides total and
per-meal dosing specifics.
PROTEIN DISTRIBUTION FOR MAXIMIZING MUSCLE GROWTH
Bodyweight
Total Daily
Protein
Dose Per Meal
(3 Meals)
Dose Per Meal
(4 Meals)
50 kg (110 lb)
80-110 g
27-37 g
20-27 g
55 kg (121 lb)
88-121 g
29-40 g
22-30 g
60 kg (132 lb)
96-132 g
32-44 g
24-33 g
65 kg (143 lb)
104-143 g
35-48 g
26-36 g
70 kg (154 lb)
112-154 g
37-51 g
28-38 g
75 kg (165 lb)
120-165 g
40-55 g
30-41 g
80 kg (176 lb)
128-176 g
43-59 g
32-44 g
85 kg (187 lb)
136-187 g
45-62 g
34-47 g
90 kg (198 lb)
144-198 g
48-66 g
36-50 g
95 kg (209 lb)
152-209 g
51-70 g
38-52 g
100 kg (220 lb)
160-220 g
53-73 g
40-55 g
110 kg (242 lb)
176-242 g
59-81 g
44-60 g
120 kg (264 lb)
192-264 g
64-88 g
48-66 g
130 kg (286 lb)
208-286 g
69-95 g
52-71 g
- 26 -
Chapter 8: How much protein maximally
preserves muscle while losing fat?
Generally speaking
Protein requirements increase depending upon the severity of
the caloric deficit, and the degree of leanness of the dieter.33 In
hypocaloric (dieting) conditions, untrained individuals with
ample/excessive body fat lose a greater proportion of their
bodyweight from fat mass compared to lean, trained
individuals, who stand to lose more lean mass. In sustained
eucaloric (weight maintenance) conditions,34 and even in
hypercaloric (weight gain) conditions,35 low protein intakes
still can jeopardize muscle mass.
Athletes’ requirements
The threat to muscle preservation in caloric maintenance and
surplus conditions via inadequate protein intake is amplified in
hypocaloric conditions. Higher protein intakes combined with
resistance training is the antidote to muscle loss in hypocaloric
conditions. A recent (2019) review by Hector and Phillips.36
concluded that an appropriate range of protein intake for
athletes in hypocaloric conditions is 1.6-2.4 g/kg.
- 27 -
Pushing the envelope
Helms et al37 conducted a systematic review that concluded
that 2.3-3.1 g/kg of fat-free mass (FFM) was appropriate for
resistance-trained subjects in hypocaloric conditions, with
needs escalating according to the severity of the deficit and
leanness level. However, out of the six studies in the review,
only three examined highly-trained competitive athletes, and
only one study examined competitive bodybuilders. The latter
study on bodybuilders by Mäestu et al38 reported that the
precontest protein intake of drug-free, world-class
bodybuilders ranged 2.48-2.68 g/kg. Chappell et al13 reported
that elite-level drug-free bodybuilding men & women who
placed in the top-5 had pre-contest protein intakes of 3.3 & 2.8
g/kg, respectively. While these data are observational and thus
are incapable of establishing causation, they’re still valuable. As
the late Jim Rohn wisely said, “Success leaves clues.”
Summing up
Boiling down protein requirements to maximize muscle
retention while dieting, it might help to delineate 3 population
tiers, thus 3 sets of recommendations:
• For athletic populations in general, the collective literature
shows that 1.6-2.4 g/kg (0.72-1.09 g/lb) of total bodyweight
- 28 -
is appropriate.24,36 You can base this calculation on target
bodyweight for those who are highly over- or underweight.
• For relatively lean, resistance-trained competitive athletes,
an appropriate range is 2.3-3.1 g/kg (1.04-1.41 g/lb) of fatfree mass. Based on a mean body fat level of roughly 18%
among the subjects in the treatment groups of Helms et al’s
systematic review (which included men and women),37 this
translates to 1.9-2.5 g/kg (0.86-1.14 g/lb) of total
bodyweight.
•
For those pushing the envelope of leanness in the pre-contest
phase of physique competition, 2.4-3.3 g/kg (1.1-1.5 g/lb) of
total bodyweight appears to optimize this goal at the elite
levels.12,13
- 29 -
Chapter 9: How should protein be distributed
through the day to maximize muscle retention
while dieting?
It’s logical that the protein distribution pattern that maximizes
muscle growth under ideal (surplus/hypercaloric) conditions
is likely to be the same pattern that maximizes muscle
retention
under
compromised
(deficit/hypocaloric)
conditions. However, there’s evidence that the goal of muscle
retention has a greater allowance for suboptimal/skewed
protein intake patterns, which we’ll cover in a moment.
Mind the hierarchy
First things first – keep in mind that in the hierarchy of
importance, total daily protein intake strongly holds the top
spot. As covered in the previous section, for physically active
and athletic individuals, which is most of you reading this, 1.62.4 g/kg (0.72-1.09 g/lb) of total bodyweight is an appropriate
target for total daily protein. 24,36 This is nearly identical to the
range that maximizes muscle growth (1.6-2.2 g/kg).24 The
distribution pattern likely to maximize muscle growth in ideal
conditions is a minimum of 4 feedings dosed at approximately
0.4-0.55 g/kg per meal.32 The latter scheme, including a
- 30 -
relatively even spread of protein doses from waking to prebed28 probably holds true for maximizing muscle retention.
Asymmetric control
Back to the first point. There appears to be an asymmetric
control system regarding muscle growth versus muscle
retention. Growth – especially beyond “newbie gains” – is more
difficult to accomplish than merely preserving existing muscle
mass. The mechanisms underlying this observation are poorly
understood. Perhaps it’s simply more energetically expensive
to fuel the molecular processes involved with muscle growth.
The body’s homeostatic drive resists changes; it fights to
neutralize shifts in the status quo, perceiving continued muscle
growth beyond normal/baseline levels as a threat to survival,
for reasons not definitively known. Compounding this, there’s
the messy matter of striking a balance (or even a compromise)
between maximizing the rate of muscle growth while
minimizing excessive gains in body fat.
Regardless of the above speculations, the big point to take
home is that muscle retention in hypocaloric conditions has
been observed in the absence of an idealized protein
distribution through the day. This has been most saliently
- 31 -
demonstrated in recent time-restricted feeding (TRF) studies
involving a formal resistance training protocol, where protein
intake was adequate (at least 1.6 g/kg) and equated between
the groups in the comparison.
Emerging data
To date, there are three studies that fit the above criteria. An 8week study by Moro et al39 was dubbed the Leangains study
since it tested the 16:8 fast:feed cycle popularized by Martin
Berkhan. A 3-meal TRF pattern consisting of 16-hour fasting/8hour feeding cycles (16/8 TRF, meals occurred at 1 pm, 4 pm,
and 8 pm) was compared with a conventional/control diet with
3 meals distributed within 12-hours (meals occurred at 8 am,
1 pm, and 8 pm) in resistance-trained men. Training occurred
between 4 pm & 6 pm. No significant changes in lean mass
occurred in either group. Interestingly, greater fat loss
occurred in TRF.
A subsequent study by Tinsley et al40 conducted a similar
comparison in resistance-trained women. Meals in TRF
occurred between 12 pm and 8 pm, while the control group
self-selected their meal times throughout the day without
timeframe restrictions. Training occurred between 12 pm & 4
- 32 -
pm. Lean mass increased in all groups, but fat loss only
occurred in the TRF. With both of these studies being freeliving designs rather than tightly controlled in-patient designs
where all intake is lab-provided and subjects are closely
supervised, the most plausible explanation was that the
superior fat loss of TRF was due to lower energy intake. The
latter speculation is supported by existing research showing a
20-30% energy intake decrease in ad libitum (unrestricted)
TRF conditions.41
Most recently, Stratton et al42 reported a lack of difference
between the effects of an 8-hour TRF and a normal diet in
recreationally trained subjects undergoing resistance training
at a 25% caloric deficit for 4 weeks. Body composition changes
(lean mass preservation and fat loss) and strength/power
improvements were similar in both groups. This lack of fat loss
advantage breaks the momentum of the previous TRF +
resistance training studies.39,40 It’s notable that Stratton et al’s
study involved more rigorous compliance measures than in
previous research. Subjects were interviewed during each
workout, where dietary logs were reviewed at the beginning of
each week. Furthermore, a 4-compartment model that
employed dual X-ray absorptiometry (DXA), bioelectrical
impedance analysis (BIA), air displacement plethysmography
- 33 -
(ADP, also called BOD POD), and ultrasonography was used to
assess body composition.
Summing up
Based on the limited research thus far, we can conclude that an
8-hour feeding window is apparently not a threat to muscle
retention. A welcome side-effect is that TRF has the potential to
facilitate fat loss – but not likely via any “magic” aside from less
opportunity to eat. A fat loss advantage of TRF + resistance
training has been seen in two39,40 out of the three studies thus
far examining the question. 39,40,42 So, the potential advantage is
there, but it’s not without dispute.
With that said, there are unanswered questions worth
pondering. Can 2-3 protein-rich meals per day be as effective
as 4 or more protein-rich meals for the goal of retaining muscle
mass in hypocaloric/dieting conditions? I’m confident in saying
that 3 meals within an 8-hour period can do the trick, since we
have consistent evidence of that in resistance trainees.39,40,42
Furthermore, a meta-analysis by my colleagues and I found
that in hypocaloric conditions, meal frequency overall had
minimal influence on body composition even in a general lack
of resistance training across studies included in the metaanalysis.43
- 34 -
At this point, we can only speculate what the limits of
suboptimality are in terms of protein distribution through the
day. When forming guidelines for application, practicality and
tolerability diminishes sharply below 3 meals per day for most
individuals. Nevertheless, the question is interesting, and also
relevant to dieters with a preference for lower meal frequency.
Based on my observations, I’d speculate that as low as 1-2
protein-rich meals per day – although not feasible for many –
can still retain muscle mass, given that resistance training and
macronutrition are sound, and the energy deficit is not severe
(not allowing more than an average of 1% of BW to be lost per
week).
- 35 -
Chapter 10: How does protein intake influence
recomposition?
Recomposition, nicknamed “recomp” by the fitness
community, is the coveted holy grail. It’s important to keep in
mind that recomp capacity diminishes alongside the
progression of an individual’s training status.44 Put more
simply, recomp happens more dramatically in untrained (or
previously trained) folks with excess body fat. The closer you
are to your potential, the less available margin there is for
recomp. With advancing proximity to your potential, recomp
becomes an impractical target. Advanced trainees and most
later-intermediates are best served by focusing on one goal at
a time: fat loss or muscle gain, not both simultaneously. For an
in-depth discussion of what distinguishes beginners,
intermediates, and advanced trainees, refer to the August 2019
issue of AARR.
The hierarchy of recomp capacity, from greatest to least, is: 1)
formerly trained folks with excess body fat, 2) overweight
novices, 3) intermediates, 4) advanced trainees. I’d like to
briefly discuss the recomp advantages of formerly fit folks. This
is the profile of those who make the most dramatic before-after
- 36 -
transformations, especially if they over-ate while remaining
sedentary for a prolonged period.
There are at least two potential mechanisms underlying this
ability of the formerly fit to dramatically rebound back into
shape. Training increases the number of myonuclei within the
muscle fibers.45 Strength & size gains can thereby be expedited
via increased mitochondrial remodeling. Training-induced
myonuclear increases are resistant to apoptosis (cell death),
and remain intact despite extended time off from training.46
Another potential mechanism is the persistence of traininginduced increases in capillarization (an increase in vascular
networks within the muscle).47 As a result, the rebound gains
in previously trained individuals are significantly faster than
the gains seen in beginners who’ve never trained before. When
you combine these mechanisms with greater neural efficiency
reducing the learning curve of the exercises, it’s clear that the
recomp advantages of previously trained folks (who have
gained body fat) put them at the top of the hierarchy.
Summing up
Recomp does in fact occur across a range of populations.
However, recomp capacity diminishes alongside increased
- 37 -
training status. Another consistent finding is that higher
protein intakes are more conducive to recomp. A nicely done
review paper by Bakarat et al44 is the first of its kind in the peer
reviewed literature to specifically examine the recomp
phenomenon. Here are the authors’ practical application
points, relayed verbatim from the manuscript (proteinoriented points italicized by me):
• Implement a progressive RT regimen with a minimum of 3
sessions per week.
• Tracking rate of progress, and paying attention to
performance and recovery can be important tools to
appropriately adjust training over time.
• Consuming 2.6-3.5 g/kg of FFM (fat-free mass) may increase
the likelihood or magnitude of recomposition.
• Protein supplements (i.e., whey and casein) may be used as a
means to increase daily dietary protein intake as well as a
tool to maximize muscle protein synthesis. This may be of
greater importance postworkout as a means to maximize the
recomposition effect.
• Prioritizing sleep quality and quantity may be an additional
variable that can significantly impact changes in
performance, recovery, and body composition.
- 38 -
Chapter 11: How does protein timing (pre,
during, and post-exercise) impact athletic
performance?
I’ll begin by saying that protein per se (especially compared to
total caloric intake and carbohydrate intake in particular) has
minimal utility as a fuel for enhancing athletic performance.
Although we can end this discussion here, it’s useful to know
the key pieces of research on this topic. It’s also useful to know
the primary rationale, which is to prevent muscle protein
breakdown (MPB), which can indirectly impact performance if
it manifests as a loss of muscle mass. Another justification for
the intake of protein or amino acids during exercise is to
prevent central fatigue, but this is a hypothesis that has largely
failed across multiple studies.48,49
Pre-exercise
On the pre-exercise front, the only study to date which directly
compared protein with other macronutrients on endurance
performance was back in 2002 by Rowlands and Hopkins.50
Twelve competitive cyclists ingested either a high-fat, highcarbohydrate, or high-protein meal 90 minutes prior to a test
involving sprinting and 50 km performance. No significant
performance differences were seen between the treatments
- 39 -
compared. As for strength performance, to my knowledge,
there is no study specifically comparing pre-exercise protein
with other macronutrients.
During exercise
A crucial yet commonly overlooked factor influencing the
ergogenic potential of intraworkout nutrition (protein or
other) is the presence versus absence of preworkout nutrition,
which from a bioavailability standpoint, can function as
intraworkout nutrition, considering the time course of
digestion and absorption, which can last several hours. In any
case, in the most recent meta-analysis to examine the effect of
protein & carbohydrate co-ingestion versus carbohydrate-only
on endurance performance, Nielsen et al49 reported that when
carbohydrate intake was equated, the condition with more
protein increased endurance capacity. However, this was due
to greater total energy intake. In comparisons that equated
total calories, there was no endurance performance advantage
of a carb-protein mix versus carbs alone.50
Again, depending on how close to the start of the bout,
preworkout nutrition can function as intraworkout nutrition.
For example, when 45 grams of whey is ingested alone, it takes
about 45 minutes for circulating amino acid levels to peak, and
another 2 hours to return to baseline levels.51
- 40 -
As such, the question of intraworkout protein intake only
applies to fasted resistance training, which has limited
relevance to the real world. Given this far-fetched scenario, a
case can be made for intraworkout nutrition, and indeed there
is evidence of its benefit for resistance trainees. Bird et al52
found that a beverage containing carbohydrate and essential
amino acids suppressed MPB. This finding is potentially
relevant to those with no option except to train immediately
upon waking, where strength gains would be compromised
with continued net losses in muscle protein. I’ll reiterate that
this was observed in fasted conditions minus any pre-exercise
nutrition, which is far-fetched for resistance training. For those
interested in a deeper dive into the research on intra-workout
protein consumption & endurance performance, it’s been
thoroughly examined in the July 2020 issue of AARR.
Post-exercise
A recent meta-analysis by Craven et al53 reported that protein
co-ingested with carbohydrate does not expedite post-exercise
glycogen resynthesis (or subsequent exercise performance)
compared to carbohydrate alone, especially when the dosing is
at or near 1.0 g/kg/hr. This echoes the recommendations of
recent position stands on post-exercise carbohydrate dosing
(1-1.2 g/kg/hr) for maximizing rates of glycogen replenish- 41 -
ment under time-constrained conditions where competitive
endurance bouts are separated by less than 8 hours.18, 54
Summing up
In perhaps the most anticlimactic sum-up ever, protein timing
is a relative non-factor in relation to athletic performance. It
can even be said that maximizing athletic performance is
partially a matter of not letting your protein intake get in the
way of your carb intake. Although there’s the potential benefit
of intraworkout protein intake for the purpose of mitigating
muscle protein breakdown to indirectly preserve strength, this
only applies to an absence of preworkout (and/or
postworkout) nutrition. The “anabolic window” concept will be
addressed in the next section where protein timing & muscle
growth are discussed.
- 42 -
Chapter 12: How does protein timing (pre,
during, and post-exercise) impact body
composition?
Let’s first establish the reality that total daily nutrient & calorie
intake have the greatest impact on body composition. In the
ISSN’s position stand on diets & body composition,33 I called the
sum of those totals “the cake,” while timing of its constituents
is “the icing.” Protein timing is of distant secondary importance.
It’s common for folks to fall prey to marketing hype and guruism that puts timing up on a magic pedestal, in opposite order
of importance. Get the cake right first, then you can apply the
icing.
Pre-exercise
There’s an interesting line of research showing that protein
taken prior to exercise results in greater increases in energy
post-exercise expenditure compared to carbohydrate.55,56
However, short-term differences in energy expenditure don’t
guarantee advantages in body composition change over the
longer-term. A direct comparison of pre- versus post-exercise
protein intake by my colleagues and I failed to show any
- 43 -
meaningful body composition advantage to either protocol.57
I’ll touch upon this one again in a moment.
During exercise
As mentioned in the previous section, Bird et al52 showed that
lifting-induced muscle protein breakdown (MPB) was
suppressed by a liquid carb/essential amino acid mixture. The
same caveat applies: the threat of MPB is likely limited to fasted
training sessions. Even so, the body is often smarter than we
give it credit for. Deldicque et al58 reported a greater anabolic
signaling response to the post-exercise meal after fasted
exercise, compared to exercise in fed conditions. It’s possible
that despite the inherently catabolic nature of training in fasted
conditions, the body amplifies its use of the post-exercise
feeding, to supercompensate, and preserve homeostasis after
perceiving an energy crisis (thus a threat to survival).
Nevertheless, the schedule constraints of some individuals
might necessitate immediate commencement of the training
session upon waking. In this case, intraworkout protein might
be justified if the goal is to pull all theoretical stops to
maximally protecting against muscle catabolism. The provision
of default hydration can’t hurt either, given the obvious refrain
from drinking fluids during sleep.
- 44 -
Post-exercise
Again, we have to think in terms of cake versus icing. Regarding
body composition effects, we’re definitely in icing territory.
The “post-exercise anabolic window” concept was brought to
the general fitness & bodybuilding audience in the early 2000’s,
thanks to Ivy and Portman’s research, and their popular
paperback Nutrient Timing: The Future of Sports Nutrition.59
The general premise was that the timing of specific nutrients
immediately post-exercise (quickly absorbed protein and
carbs) could make or break muscular gains.
The implication was that nutrient timing within the “anabolic
window” (within an hour postexercise) was more important
than totals by the end of the day.60 This principle got so deeply
ingrained in the mantra of trainees and coaches, it became
accepted as a matter of fact. However, Ivy & Portman’s
premises were based on short-term anabolic response studies
that measured muscle protein synthesis (MPS) and/or
glycogen resynthesis. Longitudinal studies (lasting several
weeks or months) examining protein timing’s effects on
muscular adaptations to resistance training told a different
story. Several studies published over the decade following Ivy
& Portman’s book yielded highly equivocal results, casting
- 45 -
considerable doubt upon the postexercise anabolic window
concept.
In light of these mixed results across multiple protein timing
studies, my colleagues and I conducted a meta-analysis of the
relevant research.61 We defined protein-timed conditions as
protein ingestion within an hour of either side of the resistance
training bout, while non-timed conditions involved a minimum
of 2 hours of protein neglect on both sides of the training bout.
Basic analysis (not accounting for covariates such as total daily
protein) showed a minor advantage of protein timing on
hypertrophy. However, regression analysis found that this
effect was due to greater total daily protein intake in proteintimed conditions compared to the non-timed conditions (1.66
vs. 1.33 g/kg, on average). A subanalysis of the studies that did
equate total daily protein still failed to show an advantage of
protein timing. So, we concluded that if an anabolic window for
protein intake exists, it appears to be greater than the one-hour
before and after a resistance training session.
Summing up
Keep in mind that the following bullet points sum up protein’s
role in this particular topic (timing for athletic performance).
- 46 -
It’s not a comprehensive treatise on nutrient timing; this book
is focused on protein. The role of carbohydrate timing in
exercise performance is covered in-depth in the April & May
2020 issues of AARR.
• Pre-exercise protein has the potential to increase postexercise energy expenditure to a greater degree than
carbohydrate. Whether these short-term effects can manifest
as body composition improvements is speculative in the
absence of data.
• Protein and carbs consumed during exercise (intraworkout)
can suppress muscle protein breakdown, but the relevance
and applicability of this is limited to overnight-fasted
conditions, and the absence of preworkout nutrition.
• Intraworkout nutrient consumption is not necessarily
beneficial in the context of a preworkout meal already being
digested and absorbed (in which case it can actually be
redundant & superfluous). If intraworkout intake is
personally preferred, that’s fine. It generally won’t hurt, and
can help in certain cases.
• Instead of focusing on a narrow post-exercise “anabolic
window,” the period between the pre- & postworkout meal
(the periworkout period) should be the focus.62
- 47 -
• The anabolic effect of a protein-rich meal is 3-5 hours,
potentially longer, depending on meal size and composition.
The preworkout meal in many cases can dictate the
postworkout environment.
• Determined by preference & tolerance, liquid or solid meals
can be consumed at any point within the 3-5 hour
periworkout period.
• Protein dosing in both the pre- & postworkout meals should
maximize the anabolic response (0.4-0.55 g/kg).32
• Note the periworkout period in green, which varies in length
according to individual variables such as meal size, form, and
composition:
PERIWORKOUT TIMING MODEL: THE “ANABOLIC GARAGE DOOR OF PEACE”
- 48 -
Chapter 13: How does BCAA supplementation
affect body composition?
Well hyped, well loved
Branched-chain amino acids (BCAAs) are one of the most
popular supplements among recreational and competitive
athletes. Chappelle et al63 recently reported that among highlevel, drug-free competitive bodybuilders, BCAAs were the
third most commonly used supplements, with the first and
second being protein powder and multivitamins, respectively.
Mechanistic rationale
The BCAAs are leucine, isoleucine, and valine. The BCAAs
happen to be 3 of the 9 essential amino acids (EAAs). Of the
BCAAs, Leucine is considered to play a key role in driving
muscle protein synthesis (MPS), suppressing muscle protein
breakdown (MPB), and activating anabolic signaling.64 The
“leucine threshold” where MPS is stimulated above resting
levels, is a loosely defined dosing threshold of at least 1-2 g
leucine, with the upper end being more applicable to older
subjects.65 Jackman et al66 showed that post-exercise BCAA
supplementation, even in the absence of other amino acids,
increases myofibrillar MPS and mTORC1 signaling. BCAA
- 49 -
supplementation has also been shown to reduce delayed onset
muscle soreness (DOMS),67 which implicates BCAA in the
suppression of exercise-induced muscle damage.
But does it work?
Short-term anabolic response data is useful for generating
hypotheses and investigating potential mechanisms. However,
what matters most is whether BCAA supplementation actually
enhances muscle growth or fat loss under relevant conditions.
This can only be investigated via longitudinal studies lasting
several weeks or months. To date, Dudgeon et al68 conducted
the only study to show superior body composition effects of
BCAA supplementation versus control conditions in resistance
trainees consuming optimal total daily protein (≥1.6 g/kg).
However, this study was so full of errors and inconsistencies,
my colleagues and I were compelled to point them out in a
formal letter.69 In contrast to Dudgeon et al’s findings,68 there
are at least four studies involving a structured resistance
training protocol that found no significant effects of BCAA
supplementation on body composition or strength compared
to placebo.70-74
A recent study 16-week study by Ooi et al75 did not involve
resistance training, but compared 3 groups in a 500 kcal deficit:
- 50 -
1) standard-protein (14%) plus placebo as a control condition,
2) standard protein plus BCAA dosed at 0.1 g/kg/day, and 3)
high-protein (27%) plus placebo (HP). Fat mass loss was
similar across the groups. Although the differences in lean mass
loss didn’t reach statistical significance, the high-protein group
lost the least lean mass, with the BCAA and control groups
coming in second and third in this regard.
These results align with the concept that the whole (intact
protein) is more than the sum of – some of – its parts (BCAAs).
Even the non-essential amino acids (NEAAs) can function
integrally with the other components of the protein. To
illustrate this, I’ll quote an excerpt from a thought-provoking
review by Hou et al:76
“Although EAA and NEAA had been described for over a century,
there are no compelling data to substantiate the assumption that
NEAA are synthesized sufficiently in animals and humans to meet
the needs for maximal growth and optimal health. NEAA play
important roles in regulating gene expression, cell signaling
pathways, digestion and absorption of dietary nutrients, DNA
and protein synthesis, proteolysis, metabolism of glucose and
lipids, endocrine status, men and women fertility, acid–base
- 51 -
balance, antioxidative responses, detoxification of xenobiotics
and endogenous metabolites, neurotransmission, and immunity.”
Summing up
So, does BCAA supplementation enhance body composition?
That’s highly unlikely – especially given sufficient total daily
protein intake. With scant exception, studies involving
resistance training fail to support the BCAA supplementation’s
effectiveness for either body composition or strength
improvements beyond placebo. Evidence aside, from a logical
and theoretical standpoint, BCAA supplementation is difficult
to justify. High-quality dietary protein sources are already
composed of 18-26% BCAA. To quote Kevin Finn, “Taking
BCAAs is like turning the sprinklers on when it’s raining out.”
A better alternative to taking BCAA is to spend your money on
high-quality protein. You’ll get the BCAAs, the rest of the EAAs,
and multiple nutritive cofactors within the food matrix that can
enhance muscle growth, health, and exercise performance. It’s
a win-win: you save money and get more benefits.
- 52 -
Chapter 14: How does a high protein intake
impact ketosis?
Under normal, non-dieting conditions, circulating ketone levels
are low (<3 mmol/l). Aside from completely fasting, ketosis is
attained by restricting carbohydrate to a maximum of ~50 g or
~10% of total energy, with the predominance of energy intake
from fat (~60-80% or more, depending on degree protein and
carbohydrate displacement).33 This brings circulating ketone
levels to a range of ~0.5-3 mmol/l. The primary ketone in the
blood is β-hydroxybutyrate (BHB). Ketogenic diet proponents
claim rather wishfully that greater degrees of ketosis provide
greater benefits for dieters.
In their book The Art and Science of Low Carbohydrate
Performance,77 keto research pioneers Jeff Volek and Stephen
Phinney recommend blood BHB levels ranging 0.5-3.0 mmol/l
to achieve “optimal fuel flow during keto-adaptation.” They
also specifically define “nutritional ketosis” as a BHB range of
1.0-3.0 mmol/l. They also recommended a relatively low
protein intake (0.6-1.0 g kg of lean mass). Readers took this as
gospel, and avoided high protein intakes for fear of proteinmediated gluconeogenesis kicking them out of ketosis.
- 53 -
Moderate protein in keto diets has been espoused in the peer
reviewed literature as well. Quoting Paoli et al: 78 “…it is not
correct to equate a ketogenic diet with a high protein diet,
because the state of the art ketogenic diets are normoproteic
thus the daily amount of protein is about 1.2-1.5 g of protein per
kg of body weight.” However, there are enough data from
controlled intervention trials to confidently say that protein
intakes beyond traditional recommendations are still
permissive of BHB levels that would make keto proponents
happy.
Summing up
Here are the data of studies demonstrating that high protein
intakes can still allow blood ketone levels that fall within the
commonly cited range that qualifies as ketosis (0.5-3.0
mmol/l).79-81 Note that two of the three studies below yielded
the magical range of blood ketones (1.0-3.0 mmol/l) promoted
by keto connoisseurs. Please note that I’m being completely
facetious when I say magical. Whether ketogenic dieting is
good, bad, or neutral depends on individual goals and
preferences.
- 54 -
Although it’s slightly off-topic from this book, it’s worth
mentioning that there’s nothing inherently superior about
ketogenic dieting vs. non-ketogenic dieting for altering body
composition or improving performance. See the keto FAQ in
the August 2018 issue of AARR, or the ISSN Position Stand on
Diets & Body Composition for more details on ketogenic diets.
STUDIES SHOWING KETOSIS DESPITE HIGH-PROTEIN DIETS
Publication
Population
Protein Carb
Blood
intake
intake
ketone
level
Wilson JM, et al. 25 college-aged 1.7 g/kg 31 g/day 1.0 mmol/l
J Strength Cond
resistanceRes. 2020
trained men
Dec;34(12):3463374. [PubMed]
Burke LM, et al. J 21 elite race
Physiol. 2017 May walkers
1;595(9):27852807. [PubMed]
Volek JS, et al.
Metabolism. 2016
Mar;65(3):100-10.
[PubMed]
2.2 g/kg
33 g/day 1.8 mmol/l
20 elite ultra2.1 g/kg
marathoners &
ironman distance
triathletes
82 g/day 0.7 mmol/l
- 55 -
Chapter 15: How does protein restriction
influence longevity?
Many people have heard the claim that protein restriction
increases lifespan. Many have accepted it unquestioningly, and
filed it into their belief system. It’s a convenient, common claim
for folks whose dietary ideology makes getting optimal protein
targets somewhat of a pain in the butt. After all, optimizing
protein intake can require extra effort, strategy, and expense. It
would be much simpler (and cheaper) to just skate by on a low
protein intake, thinking you’re getting the added benefit of
greater longevity.
Rogue offspring of caloric restriction
Protein restriction is an offshoot of caloric restriction (CR),
which is a prolifically studied tool for promoting longevity in
animal models. However, a stiff challenge to the protein
restriction for longevity model is that it’s not rooted in human
research. For example, glucose and amino acid restriction have
been shown to extend the lifespan of Saccharomyces
cerevisiae, a single-celled fungus, better known as brewer’s
yeast.82 An abundance of longevity experiments have been
done on yeast, due to its short lifespan and ease of trial
repeatability.
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Flies, worms, and rodents (oh my)
Lifespan increases from amino acid or protein restriction have
also been seen in flies, worms, and rodents. In non-human
primates, however, the findings have been equivocal, and
protein restriction cannot necessarily be separated from
calorie restriction (CR). Notably, in rhesus monkeys, the
Wisconsin National Primate Research Center showed
significantly lower mortality in the CR group compared to
controls, whereas the National Institute on Aging reported no
significant difference.83 Keep in mind that animal data do not
automatically apply to humans. Animal data are, at best,
hypothesis-generating food for thought, subject to replication
(or refutation) by controlled intervention trials on…you
guessed it, humans.
A tale of two monkey studies
This leads us to human research on protein restriction. Like the
non-human primate data, human data are also equivocal.
Exemplary of this mixed bag results is Levine et al’s analysis84
of the Third National Health and Nutrition Examination Survey
(NHANES III) data combined with follow-up data from the
National Death Index. Moderate protein intakes (10-19% of
calories from protein) and high protein intakes (≥20% of
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calories from protein) had higher risks of diabetes-related
mortality than the low protein intakes (<10% of calories from
protein) group. Among those aged 50-65 years, higher protein
intakes increased risks of all-cause and cancer-related
mortality. However, in subjects aged 66 years and older, the
high protein intakes were associated with the opposite effect –
lower all-cause and cancer-related mortality.
In addition to the dichotomous results, it’s worth reiterating
that Levine et al84 reported observational data, incapable of
demonstrating cause-and-effect. The authors conceded that a
major limitation with their findings is that they were based on
a single 24-hour dietary recall, followed up by as much as 18
years of mortality assessment.
Beloved BCAA escapes the chopping block
Branched chain amino acid (BCAA) intake has been implicated
in higher protein intakes’ purported antagonism of health and
longevity via driving the mTOR pathway, and somehow
facilitating insulin resistance.85 Again, this concern is based on
rodent data and observational leaps. It’s poorly justified, given
the importance of these metabolic pathways in preventing
sarcopenia. In contrast to the observational data drawing an
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association between circulating BCAA levels insulin resistance
in obese and diabetic patients,85 human intervention data failed
to support this. In a recent crossover study on obese,
prediabetic subjects, Woo et al86 found that high-dose BCAA
supplementation (20 g/day) did not affect glucose metabolism.
Muscle-centric approach as an antidote to aging
A recent review by Burd et al87 presented a muscle-centric
perspective of optimizing protein intake through the lifespan
for the purpose of optimizing health. The RDA (0.8 g/kg) fails
to optimize the retention of muscle mass, especially in the
elderly. The range cited by Burd et al (1.2-1.5 g/kg)87 is very
close to the 1.2-1.6 g/kg reported by Phillips et al7 for
preserving muscle mass and optimizing metabolic health
through the aging process in the general population.
Importantly, Burd et al87 and Phillips et al7 based their
conclusions on randomized controlled trials that consistently
favor higher protein intakes for improving body composition
and a wide range of cardiometabolic health parameters. This is
in stark contrast to the animal data (much of it from rodents
and invertebrates) and observational data (incapable of
showing causation) suggesting the low-balling of protein
intake for longevity.
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Sarcopenia (age-related progressive loss of muscle mass and
function) is one of the greatest health threats faced by older
adults.88 A loss of muscle mass generally begins at ~50 years
and progresses at a rate of ~0.8% per year.87 Strength decline
is ~2–3% per year. At 70 years of age, there is the potential for
a 16% loss of muscle mass and 50% drop in strength compared
to younger adulthood.
The good news is that sarcopenia is preventable and treatable
with nutrition and training interventions. A proactive, musclecentric approach needs to replace the unfortunately common
reactive approach, where advancing age finally catches up with
a sub-optimal protein intake. If anything, age-related anabolic
resistance (a decreased anabolic response to protein feedings)
actually warrants an increase in protein intake with advancing
age, not a decrease.7
Summing up:
I’ll end off by quoting an excerpt from the December 2017 issue
of AARR, which I feel sums up this topic well:
“For increasing longevity, the case for protein and amino acid
restriction is relatively weak, disjointed, and hypothetical
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compared to the case for raising protein intake above the
currently recommended amounts by public health organizations.
The benefits of protein restriction are rooted in animal data,
whose results are largely divergent from controlled human data
examining a broad spectrum of endpoints that define healthy
aging.
Given the interplay of factors involved with the development of
the age-related pathologies, it’s not surprising that the bestsupported defense against sarcopenia and its related conditions
is a two-pronged intervention: optimized dietary protein intake
and exercise (especially resistance exercise).”
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Chapter 16: How does advanced age impact
protein utilization and dosing requirements?
Anabolic resistance is characterized by a diminished muscle
protein-synthetic (MPS) response to protein/amino acid
feeding & exercise.89 This is typically an age-related
phenomenon that contributes to the decline of muscle mass
and function. Precise mechanisms are yet to be definitively
elucidated, but the “use it or lose it” principle (applied to
muscle), is a prime contributor. Decreased protein and total
energy intake, in addition to increased physical activity are the
main interplaying culprits in the development of anabolic
resistance. Per the hierarchy of importance regarding protein
variables, total daily intake is at the top. According to expert
panel positions (PROT-AGE and ESPEN),6 individuals over age
65 have the following protein requirements: 1.0-1.2 g/kg for
healthy folks, 1.2-1.5 g/kg in cases of acute or chronic illnesses,
and 2.0 g/kg for those with severe illnesses, injuries, or
malnutrition.
Moore et al90 conducted a comprehensive summation of their
prolific research in this area, and concluded that MPS reached
a plateau in younger men (early 20’s) with a protein dose of
0.24 g/kg BW, while in older men (early 70’s) MPS reached a
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plateau after ingestion of 0.40 g/kg BW. Note that these are
mean values (averages), so the upper 95% CIs (high-end limits)
are worth pointing out, since individual response potentially
can dictate requirements significantly above the mean. Quoting
their discussion of this important nuance about protein doses
that max-out MPS (my bolding for emphasis):90
“Additionally, it should be noted that the breakpoint observed in
the present study would reflect the estimated average
requirement to maximize MPS and, as such, the acute protein
intake may be as high as ~0.60 g/kg for some older men
(depending on the presence of potential contributing factors to
the “anabolic resistance” of MPS) and ~0.40 g/kg for some
younger men.”
A notable example of a higher protein dosing ceiling for
maximal MPS in older subjects than we previously thought, is a
recent study by Park et al.91 In older untrained adults (mean
age 69.3 years), 70 g protein from beef patties elicited greater
MPS than 35 g in the non-trained state. Without an
intermediate dose between 70 & 35 g, questions still remain
about the precision of where beyond 30 g the anabolic ceiling
was for this particular population. In contrast, Holwerda et al,92
examined the anabolic dose-response to 15, 30, and 45 g milk
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protein concentrate taken post-resistance exercise by
untrained older adults (mean age 66 years). Although wholebody protein synthesis was highest with the 45 g dose, MPS
plateaued at 30 g. It’s tough to explain the discrepancy between
these studies’ findings aside from the possibility that the
mixed-macronutrient meal used in Park et al91 could have been
more inherently anabolic than an isolated protein source.
It’s also worth noting that anabolic resistance is not necessarily
an inevitable fate. Breen and Phillips93 make a distinction
between the “frail” elderly (who are afflicted by various
illnesses) and the “well preserved” elderly (who are not
significantly afflicted by age-related comorbidities, and are
physically active). I prefer to call the latter “trained” elderly,
since “well preserved” sounds too much like beef jerky. Along
these lines, a systematic review by Shad et al94 included 24
studies containing 48 study arms (study groups). Overall, 18
study arms showed evidence of age-related anabolic
resistance, 30 study arms did not. Importantly, when resistance
exercise and protein/amino acid-based nutrition were
combined, only 2 of the 10 study arms showed age-related
anabolic resistance. It thus was concluded that the
optimization of resistance exercise and protein or amino acid
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consumption can produce comparable MPS responses between
young (18-35 years) and older individuals (>55 years).
Summing up
• Age-related anabolic resistance is characterized by a
diminished muscular sensitivity to protein feeding, requiring
a higher protein dose to max-out MPS in older vs younger
subjects.
• Per the findings of Moore et al,90 older subjects max-out MPS
at 0.4-0.6 g/kg per meal. Consuming this dose at least 3-4
times in the course of the day would ensure that the targeted
total is hit.
• Anabolic resistance is apparent in the general/untrained
elderly population, and especially apparent in the frail
elderly. However, this phenomenon does not necessarily
apply to healthy older subjects, especially those who
combine resistance training and proper protein feeding.93-95
Side-note: when Moore et al published their review,90
Macnaughton et al30 had not yet “shook up” the research world
with their finding that 40 g elicited greater MPS than 20 g whey
protein in young resistance-trained adults after high-volume
(full-body) resistance exercise. It remains to be seen whether
the same protocol in older subjects would nudge the protein
dosing ceiling up even further.
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Another side-note: Moore et al’s range for older subjects (0.40.6 g/kg)90 is nearly identical to the per-meal dosing range
Brad Schoenfeld and I recommended in our paper on the topic
of protein dosing for maximizing the per-meal anabolic effect
(0.4-0.55 g/kg).32 Brad and I factored Macnaughton et al’s
work30 (among several other lines of evidence) into our
recommendations, hence our higher dosing suggestion than
the lower doses traditionally thought to only apply to older
subjects.
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Chapter 17: How much protein do adolescents
need?
Adolescence has been loosely defined as the teenage years, but
perhaps more accurately, it’s the timeframe spanning from the
beginning of puberty, to the beginning of adulthood.96 This has
been cited as the period between 10-19 years of age,96 but it’s
also been referred to as 12-18 years of age.97 Adolescence is the
second wave of rapid growth in the human life cycle, with the
first wave occurring from infancy to early childhood.98 Daily
energy requirements reflect the rapid growth that occurs
during adolescence:99,100
DAILY ENERGY REQUIREMENTS OF ADOLESCENTS (PAL = physical activity level)
11-14 years
Average PAL99
Heavy PAL100
15-18 years
Average PAL99
Heavy PAL100
Males
Females
2500 kcal
2475-3175 kcal
2200 kcal
2300-2725 kcal
3000 kcal
3450-3925 kcal
2200 kcal
2855-2875 kcal
Current ‘authoritative’ recommendations of protein intakes for
adolescents are lacking. They’re largely stuck in the RDA zone
(9-13 years: 0.95 g/kg, 14-18 years: 0.85 g/kg).101 Refer to
Chapter 3 for a discussion on the inadequacy of the RDA for
most healthy, active populations.
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Summing up:
• The RDA for protein is inadequate for most healthy, active
populations. Recent literature reviews100,102 have proposed
that the protein needs of physically active adolescents
should mirror the adult recommendations of the position
stands of the authoritative organizations.
• Recently, Berg102 proposed that adolescent athletes should
consume 1.2-2.0 g/kg, which reflects the most recent joint
position stand of the Academy of Nutrition and Dietetics,
Dietitians of Canada, and the American College of Sports
Medicine.18
• It should be noted that since the adolescent population is
undergoing particularly rapid growth, a lower-end intake
of 1.2 g/kg might not be adequate, as seen in IAAOdetermined protein requirements of children, which
ranged 1.3-1.55 g/kg.103
• For the general adolescent population, I would default to
the ISSN’s recommended intake for physically active adults
(1.4-2.0 g/kg).17
• However, needs could be higher in adolescent athletes who
go through periods of caloric restriction (i.e., for weight
class-based sports, or to meet the body composition needs
of particular competitive seasons or phases). In this case,
Hector and Phillips’ recommendation of 1.6-2.4 g/kg for
athletes in hypocaloric conditions seems warranted.36
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Chapter 18: How do sex differences influence
protein requirements?
In the history of “official” nutrition recommendations, none of
the major/authoritative scientific organizations have specified
different protein requirements for men and women. Based on
the evidence as a whole, this lack of delineation is warranted.
In the literature, there are flickers of difference, which I’ll touch
upon. The main sex-based difference relevant to estimating
protein needs is the higher proportion of body fat in women,
which defaults to a lower proportion of lean mass. Total
bodyweight-based protein estimation can therefore be skewed
toward overestimation of women’s needs (I’ll get to practical
solutions to this as we sum things up).
Sex-based differences in muscle protein synthesis (MPS) across
various populations could lead us to hypothesize that men and
women need different amounts of total daily protein to
maximize muscle growth or retention. However, this has not
consistently been the case.
A classic review by Tipton104 relayed several studies in the late1990’s and early 2000’s showing that between the sexes, there
are no differences in whole-body protein synthesis or
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breakdown, and no difference in basal level of net muscle
protein balance. Furthermore, there’s no human (or animal)
evidence that ovarian hormones inhibit muscle protein
synthesis. Subsequent research by Smith et al105 found no
meaningful differences in MPS during fasting conditions and
during hyperinsulinemia-hyperaminoacidema between young
and middle-aged adult men and women. Continuing the same
theme, Dryer et al106 found that post-exercise increases in MPS
and mTOR signaling in leg muscle is not different between men
and women.
A recent (2018), thoroughly done review by Witard et al107
reported that sex-specific differences in MPS response to
exercise and nutrition has not been consistently shown in
young adults, but in older adults, greater basal MPS rates have
been shown in older (>65 years). This can at least partially
explain their slower age-related loss of muscle compared to
older men.108
More recent data using the indicator amino acid oxidation
(IAAO) technique found that resistance-trained men required
2.0-2.38 g/kg (2.2-2.6 g/kg FFM)26 and resistance-trained
women required 1.49-1.93 g/kg (1.8-2.2 g/kg FFM),109 to
maximize the acute anabolic response (these ranges represent
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estimated average requirements and upper confidence limits).
However, the main limitation of the IAAO method is that it
assesses whole-body protein synthesis, not muscle-specific
protein synthesis.
Summing up
• Overall, there’s insufficient evidence to program different
protein targets either in total or per meal, based on sex. This
lack of meaningful difference in anabolic response to protein
feeding has been seen in the majority of studies examining
this question.
• While younger adults consistently fail to exhibit sex-based
differences in MPS response to nutrition and training, it’s
possible that the greater basal/resting MPS rates in older
women (>65 years) can explain their slower rate of muscle
loss. However, this is largely speculative, since a multitude of
genetic and lifestyle factors are involved, and can vary widely
across individuals.
•
Keeping in mind that with an optimal total daily protein
intake of 1.6-2.2 g/kg, both sexes can use 1.6 g/kg as a
baseline from which to adjust upward. It’s reasonable to
assume that women require less protein per unit of total
body mass, since they tend to carry a higher proportion of
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body fat than men. Therefore, women’s needs along the 1.62.2 g/kg range will likely hover around the lower rather than
the higher end of the range.
•
Fat-free mass (FFM)-based protein targets are more
complicated and not necessarily more accurate, but they can
satisfy some people’s OCD. 2.0 g/kg FFM (0.9 g/lb FFM) is a
reasonable baseline target for general purposes. Individuals
specifically aiming for muscle gain (as well as dieters running
a caloric deficit) can start at 2.2 g/kg FFM (1.0 g/lb FFM), and
adjust according to individual response.
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Chapter 19: How do high-protein diets impact
bone and kidney health?
Bone health
Bone health and kidney function are perhaps the most common
concerns surrounding high protein intakes. We’ll start with
bone. Who hasn’t heard the claim that protein, which is made
of amino acids, leeches calcium from bone in order to buffer the
acidity of a high-protein intake, which eventually leads to bone
loss. Well, that sounds logical on paper, but it doesn’t stand the
test of science. The following excerpt from a classic review by
Layman5 is worth quoting because it eloquently nails the
important points:
“The efficacy of calcium and protein are interrelated. Calcium
supplements are largely ineffective for remodeling of bone
matrix if protein is limiting. Positive effects of calcium appear to
require intakes of protein >1.2 g/kg to have beneficial effects. The
long-held belief that increased dietary protein could cause bone
loss as reflected in increased urinary calcium is incorrect, and
protein is now recognized to increase intestinal calcium
absorption in addition to enhancing bone matrix turnover.”
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More recently, Antonio et al110 found that a high protein intake
(averaging 2.8 g/kg) over a 6-month period in trained women
had no harmful effects on bone mineral content or density.
Subsequently, a meta-analysis by Groenendijk et al111 showed
that high (above the RDA of 0.8 g/kg) vs low protein intake
resulted in a significant decrease in hip fractures.
Kidney function
Antonio et al conducted a series of investigations on resistancetrained subjects refuting the claim that high protein intake is
an inherent threat to kidney function.112-114 An 8-week trial
involving a protein consumption at 3.4 g/kg showed no
adverse effects on renal function (or in general).104
Subsequently, a 4-month trial ranging 2.6-3.3 g/kg showed no
adverse clinical effects, including renal function.113 Finally, a 1year crossover trial involving 2.5 & 3.3 g/kg (6 months at each
protein level) showed no harmful effects on any biomarkers of
health, including liver and kidney function.114
A recent systematic review and meta-analysis by Devries et
al115 involving 28 studies and 1358 subjects compared highprotein intakes (≥1.5 g/kg body weight or ≥20% energy intake
or ≥100 g protein/day) with normal/lower-protein intakes
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(≥5% less energy intake from protein/day compared with
high-protein group) on kidney function. It was concluded that
higher protein intakes have a trivial to non-existent effect on
kidney function.
Summing up:
• Current evidence does not support concerns about high
protein intakes being inherent threats to kidney and bone of
healthy individuals.
• Protein intakes above the RDA (0.8 g/kg) are associated with
a decrease in hip fractures, and intakes below 1.2 g/kg might
not optimize calcium metabolism as it relates to bone health.
• Protein intakes as high as 2.8 g/kg for 6 months have not
shown adverse effects on bone.
• Protein intakes as high as 3.4 g/kg have not shown any
adverse effects on kidney function in the intermediate-term,
and intakes at 2.5 & 3.3 g/kg have not shown any adverse
effects on kidney function in the long-term.
• If you have (or suspect you might have) kidney disease, the
research discussed in this chapter might not apply to you.
Consult with your doctor (and if possible, your renal
dietitian) if you have any doubts or concerns.
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Chapter 20: Is there an inherent advantage to
pre-bed casein?
Cow’s milk protein consists of 80% casein and 20% whey.
Whey is the fast-digesting protein. Casein is a slow-digesting
protein, which gives it the potential for special application at
the pre-bed time point, for the purpose of a timed-release of
amino acid availability. Pre-bed protein increases amino acid
availability through the night, thus resulting in net gains in
muscle protein balance compared to…well, no protein feeding
at all.28 In light of the past several years of pre-bed protein
research, a recent review by Kim116 concluded that 40-48 g
casein ingested roughly 30 minutes prior to sleep enhances the
anabolic response in skeletal muscle – especially when this is
done in the post-exercise state.
While the above conclusion is reasonable based on the existing
findings, a potentially more practical question is whether the
timing of casein intake (pre-bed versus some other point in the
day) makes a difference on muscle growth or muscle retention
in the context of a resistance training program and optimized
total daily protein intake. The answer to this would require
longitudinal research (lasting several weeks or months. To
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date, there are only two studies that directly examine this
question, which I’ll discuss next.
Antonio et al117 found no significant effect as a result of 54
grams of casein either in the morning (before 12:00 noon) or
evening (90 minutes prior to going to bed) added to the
habitual routine of resistance-trained subjects in an 8-week
period. No between-group or within-group differences were
seen, as if the 54 g casein disappeared into thin air. The
morning & pre-bed casein groups had a baseline/habitual
protein intake of 1.7 and 1.9 g/kg respectively. It’s possible that
the additional protein was superfluous in the face of protein
intakes that were already optimized. Casein supplementation
brought protein intakes up to a total of 2.4 g/kg in both groups.
A subsequent study by Joy et al118 on recreationally trained
subjects compared the a 10-week effects of 35 g casein either
in the morning (with 35 g maltodextrin taken pre-bed) or prebed (with 35 g maltodextrin taken earlier in the day). Baseline
protein intakes of the morning and pre-bed casein groups were
not reported, but intake during the trial (including casein
supplementation) was 1.99 g/kg and 2.14 g/kg, respectively.
Both groups had significant increases in muscle strength and
mass, with no significant differences between groups.
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Summing up
The scant evidence to date does not show that specifically
timing casein before bed imparts special effects on body
composition compared to casein ingestion elsewhere in the day
– particularly in resistance trainees consuming optimal total
daily protein amounts (approximately 1.6-2.2 g/kg24). If there
is an advantage, which in theory would be greater net gains in
muscle protein balance leading to greater muscle gain or
retention, it’s been too small to detect within the
methodological parameters of the studies thus far.
It would be interesting to see future studies compare the body
composition effects of casein with different proteins taken prebed, to see if casein is actually something special at that time
period. Again, this would ideally be done via parallel arm study
involving resistance training, drawn out for several weeks.
This is not likely to happen any time soon, but if/when it does,
we’ll be ready. :)
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Chapter 21: How does postworkout whey
compare to chicken, beef, or casein for
improving body composition & strength?
The whey, chicken, & beef study
This question is relevant in light of the enduring interest in
post-exercise tactics that might enhance muscular adaptations
to resistance training. Whey has been studied extensively for
this purpose. Direct comparisons with other (non-milk-based)
animal proteins have been elusive – until 2017. An 8-week
study by Sharp et al119 compared the effects 46 g whey, chicken,
or beef protein post-exercise in resistance-trained, collegeaged men and women. A fourth group served as a control,
taking a maltodextrin-based placebo. All three protein groups
significantly increased lean body mass, and significantly
decreased fat mass, with no significant differences between
groups. The control group also showed recomposition
improvements, but not to a statistically significant degree.
The greater LBM gains in the protein groups compared to the
control group are interesting, since their dietary protein
intakes were reported to range 2.1-2.2 g/kg while the placebo
group’s protein intake was 2.0 g/kg. All of these intakes fall well
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into the realm of optimal protein dosing. In the strength
department, 1-rep maximum for deadlift and bench press
significantly increased compared to baseline for all groups,
including the control group. No significant differences between
groups were detected.
Keep in mind, the chicken and beef protein hydrolysate
powders were used instead of these proteins in their
native/flesh form. Such a comparison would be messier and
more logistically challenging, but more relevant to dietary
programming in the real-world.
What about casein vs whey?
Whey’s stimulation of muscle protein synthesis (MPS) is a
steeper/sharper spike, while casein’s MPS curve is flatter and
longer. However, acute (short-term response) studies
comparing these proteins have consistently shown no
difference in MPS120,121 or net protein balance122 when ingested
post-exercise.
Longitudinal studies measuring changes in body composition
and strength performance are mixed, with one study showing
the superiority of whey123 and two showing no significant
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difference between whey and casein ingested pre- and/or postexercise.124,125 The one study showing whey as the winner123
had a dosing protocol that makes me do a double-take every
time (1.5 g/kg; 90 g per day of the protein supplements, in
addition to their habitual diets). This study also has a higher
potential for bias since the lead investigator was also the
research director of the company that provided the whey
protein product used in the study. This obviously doesn’t
guarantee bias, but it still raises my skeptical senses. Don’t get
me wrong – I love how it validates my own high intake of whey,
but hard not to see this study as an oddity in the literature.
Summing up
The collective evidence thus far does not indicate that the
specific postworkout protein source makes a significant
difference in the enhancement of resistance training
adaptations – especially in the context of a diet containing a mix
of high-quality proteins.
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Chapter 22: How do whole eggs compare with
egg whites for muscle growth?
Acute anabolic response
van Vliet et al126 found that in healthy, resistance-trained men,
the post-exercise consumption of 3 whole eggs resulted in a
29.4% greater stimulation of muscle protein synthesis (MPS)
than 6 egg whites (a protein-equated dose). Short-term MPS
response is useful for investigating mechanism, but it’s
hypothesis-generating until things are put to the test in
longitudinal research capable of measuring changes in body
composition. Fortunately, this has been done. Let’s have a look.
Adaptations to training
Bagheri et al127 compared the 12-week effects of 3 whole eggs
vs 6 egg whites ingested post-exercise in resistance-trained
men undergoing a nonlinear, periodized, progressive
resistance training program. Total bodyweight gain in the
whole egg & egg white group was 1.7 & 1.8 kg, respectively,
indicating that a similar net caloric surplus was sustained in
both groups. Total daily protein intake in the whole egg & egg
white groups was 1.42 & 1.47 g/kg, respectively. This leaves
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open questions about whether significant differences would be
seen with optimized protein intakes of 1.6-2.2 g/kg.24
Lean mass gain was greater in the whole egg group (3.7 kg vs
2.9 kg), but not to a degree of statistical significance. Fat mass
decreased in both groups (2.0 & 1.1 kg in the whole egg & egg
white group, respectively), but this difference did not reach
statistical significance. However, body fat percentage decrease
was significantly greater in the whole egg group. Total protein
intakes in the whole egg & egg white group were respectively.
In the strength department, whole eggs resulted in significantly
greater gains in knee extension & handgrip strength.
Another factor working in the favor of whole eggs’ anabolic
potential is their significantly greater impact on serum
testosterone levels, which increased by 240 & 70 ng/dL in the
whole egg & egg white group, respectively. The clinical
significance of this testosterone hike is up for debate, but could
plausibly function as part of an anabolic mechanism beyond the
extra calories from the fat content of the yolks.
Summing up:
The scant body of research in this area shows that whole eggs
have greater acute and chronic anabolic effects than a protein- 83 -
equated dose of egg whites consumed post-exercise. An
additional effect of whole egg consumption is an increase in
testosterone. I wouldn’t say that egg yolks can make or break
body composition goals. It’s a relatively minor variable within
the multitude of programming elements that facilitate muscle
growth. However, based on the evidence thus far, including egg
yolks in the diet might provide a slight edge compared to eating
just the whites.
The data on eggs and health outcomes are a mixed, equivocal
mess
that’s
difficult
to
distill
into
definitive
recommendations.128 However, considerable evidence has
mounted in defense of eggs, challenging traditional concerns
and caveats about whole egg consumption..129 If you’re worried
enough, keep regular track of your bloodwork to note any
changes (good or bad) that might correlate with your egg
intake, and heed the advice of your doctor.
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Chapter 23: If collagen is considered a lowquality protein, does that make collagen
supplements useless?
Collagen is the most abundant protein in the entire animal
kingdom.130 It’s also the most abundant protein in humans (and
most vertebrates), comprising up to a third of total bodily
protein mass.131 There are 16 types of collagen in the body, 8090% of which are types 1-3. The different collagen types and
their characteristics are tabulated here.130
However, anyone who’s taken a basic nutrition course was
taught that collagen is the one animal protein source that’s
comparatively inferior. Collagen has a low indispensable-todispensable amino acid ratio, and is devoid of the essential
amino acid tryptophan, which has led to the classification of
collagen as an "incomplete" protein.132 However, the high
glycine, proline, and hydroxyproline content of collagen makes
it functionally unique among other proteins. And as the saying
goes, that’s where the magic happens.
Summing up:
• The current evidence supports the potential of supplemental
collagen for strengthening ligaments & tendons,133,134
mitigating osteoarthritis & osteoporosis,135,136 reduced- 85 -
•
•
•
•
activity
joint
pain,137,138
and
dermatological
applications.139,140
Although collagen supplementation has been shown to
increase lean body mass and strength in older141,142 and
younger adults,143 these studies did not directly compare
collagen with another protein source. In direct comparisons,
whey has outperformed collagen for decreasing android
fat144 and increasing acute & longer-term muscle protein
synthesis.145
The effective dosing ranges 8-15 g.135,141-143 Increased plasma
glycine and proline levels have been reached with 8 g/day.
12g/day improved symptoms of osteoarthritis &
osteoporosis.
15 g/day resulted in lean mass & strength gains (note that
these results were not from direct comparisons to other
proteins).
- 86 -
Chapter 24: How do plant proteins compare to
animal proteins for muscle growth?
The popularity of plant-based diets has been on the rise as of
roughly the past decade.146 Plant proteins have long been
considered inferior to animal proteins due to their lower
digestibility & lesser proportion of essential amino acids (EAA),
including key anabolic drivers, the branched-chain amino
acids; leucine in particular.147 Nevertheless, claims of plantbased proteins being on a level playing field with animal-based
proteins for supporting muscle growth have been gaining
momentum in recent years, so let’s have a look at the evidence.
Short-term anabolic response
Whey has outperformed soy in acute muscle protein synthesis
(MPS) studies in both young148 and old subjects.149 And frankly,
these findings were not surprising, given the higher EAA
content of whey. The acute anabolic response superiority of
whey has also been seen in direct comparisons to wheat
protein,150 as well as pea-based plant protein blends.151
Monteyne et al152 recently reported that a fungus-derived
protein product (mycoprotein) outperformed milk protein for
raising MPS.23 However, the greater amount of protein (31.5 vs
26.2 g) and kcal (238 vs 108) in the mycoprotein treatment
- 87 -
confounds the comparison. More recently, Pinckaers et al,153
similar elevations in MPS were seen in a comparison of corn
protein, milk protein, and a corn-milk protein blend.
Chronic effect studies
In 2013, Joy et al154 compared post-exercise whey and rice
protein isolate supplementation in resistance-trained subjects.
Both treatments similarly improved body composition and
exercise performance. Babault et al155 shook up the protein
world in 2015 when they published findings showing the
superiority of pea protein over whey for increasing muscle
thickness in untrained subjects. Of course these results are
intriguing, but I’d view this finding with caution until this study
is replicated. Nieman et al156 recently reported that whey
outperformed pea protein at suppressing blood biomarkers of
muscle damage from 5 days of eccentric-based exercise.
A 2018 meta-analysis by Messina et al157 examined the effect of
animal protein versus soy protein supplementation on muscle
size and strength gains in subjects undergoing resistance
training. Of the 9 studies, 3 favored dairy protein, and 6 studies
showed no significant advantage of either protein type. None of
the studies actually found soy to be the superior performer.
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A recent 12-week study by Hevia-Larraín et al158 is the first to
compare the effects of a completely plant-based (vegan) diet
with an omnivorous diet on the resistance training adaptations,
under conditions of optimal protein intake (at least 1.6 g/kg).
Both groups showed increased lean mass, cross-sectional area
of type 1 & 2 fibers, and leg press strength, with no differences
between groups. Body fat was unchanged compared to baseline
in both groups. Protein supplementation in the omnivores and
vegans were in the form of whey (41 g/day) and soy protein
(58 g/day), respectively. While the lack of differences is
interesting, the use of untrained subjects is the Achilles’ heel
that leaves open questions. In newbies, potential advantages in
one in treatment versus the other are often masked by an
indiscriminately robust response to whatever novel protocol is
undertaken. Replication of this study with trained subjects
would provide useful data.
Summing up
• In the majority of acute (short-term) anabolic response
studies to date, commonly used animal proteins (dairy-based
proteins in particular) have outperformed commonly used
plant-based proteins.
• Longitudinal studies capable of measuring effects on body
composition and exercise performance have been mixed,
- 89 -
with no clear advantage of animal- versus plant-based
protein supplementation.
• Only one study to date158 has compared plant versus animalbased protein supplementation in the context of a completely
plant-based (vegan) diet versus omnivorous diet, and no
between-group differences were seen in lean mass &
strength gains. A caveat is the use of untrained individuals,
who are subject to the newbie gains, which can mask
otherwise detectable differences in the treatments
compared.
• In Hevia-Larraín et al’s study,158 protein supplementation
was used to facilitate an optimal daily intake. The vegan
group supplemented with soy protein isolate (58 g/day).
• On a related note: concerns about the isoflavone content of
soy foods having feminizing effects in men are not
substantiated by the literature as a whole.159 However, this
concern is not completely unfounded, since testosterone
decreases have been reported with soy protein isolate
supplementation dosed at 20 g/day160 and 56 g/day.161
Limitations of this research aside, sole reliance on large
amounts of soy protein supplementation to hit daily protein
targets is probably a not good idea for those concerned with
hormonal effects.
- 90 -
•
Animal proteins possess an anabolic advantage (and in some
cases an ergogenic advantage) due to higher EAA content –
particularly leucine, and also due to constituents such as
taurine, carnosine, creatine,162,163 collagen,132-143 and even
cholesterol,127,164,165 none of which are present in plant foods.
•
While it’s possible for exclusively plant-based protein intake
to perform similarly to omnivorous protein intake when
enough total protein is consumed (≥1.6 g/kg), animal-based
protein is generally more anabolic on a gram-for-gram basis.
In support of this point, I’ll end off with a salient excerpt from
a recent review by Berrazaga et al:147
“Despite some contradictions, taken together, most of these
studies suggest that the difference between the anabolic effects
of plant- and animal-based proteins could be reduced with an
adequate (i.e., increased) protein intake. […] Nevertheless, at
similar protein intakes, most studies have reported a lower
ability of plant-based protein sources to stimulate protein
synthesis at the skeletal muscle level and induce muscle mass
gain compared to animal-based protein sources, especially in
older people. The lower anabolic effect of plant-based protein
sources is partly due to their lower digestibility and their lower
essential amino acid content, especially leucine, compared to
animal proteins.”
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Chapter 25: How satiating is protein, really?
Protein is considered to be the most satiating
macronutrient.166,167 This is based on an abundance of evidence
from short-term satiety response data, as well as longitudinal
studies comparing higher versus lower protein intake on
bodyweight and body composition. Before getting into that,
let’s pay a quick tribute to accuracy by getting the definitions
straight. As Bellisle et al168 eloquently put it:
“Satiation occurs during an eating episode and brings it to an
end. Satiety starts after the end of eating and prevents further
eating before the return of hunger.”
Most acute (short-term) fixed-meal studies have shown
significant reductions in hunger and increased fullness after
consuming higher versus standard protein meals.169 The most
consistent hormonal responses associated with higher-protein
meals are increases in the ‘satiety hormones’ PYY and GLP-1.
These acute findings have been reflected in longer-term studies
consistently showing the superiority of higher protein intakes
(1.2-1.6 g/kg or ≥25% of total kcal) compared to lower intakes
on weight/fat loss, weight loss maintenance, and lean mass
preservation.169-171
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A possible limit to protein dosing for satiety?
A recent 7-day crossover trial by Roberts et al172 compared the
satiating effect of a moderate-protein diet (1.8 g/kg) with a
high-protein diet (2.9 g/kg) in resistance-trained subjects in
hypocaloric conditions (20% below maintenance needs). This
7-day hypocaloric period was followed by a 3-day ad libitum
(unrestricted) period. Habitual training routines were
maintained throughout the study. There was a lack of
difference in satiety between the two groups in most of the
parameters tested.
However, it’s notable that during the hypocaloric conditions, 2
of the 9 questionnaire items favored the high-protein diet.
Specifically, subjects reported increased cravings on the
moderate-protein diet, and greater satisfaction on the highprotein diet. The authors concluded that in sum, there was
insufficient justification for recommending the high-protein
(2.9 g/kg) over the moderate-protein intake (1.8 g/kg) for the
pursuit of maximizing satiety in hypocaloric conditions, with
the exception of implementing high-protein meals to mitigate
cravings if needed. I think this study is interesting, and
provides some good food for thought. However, the 7-day
period leaves a lot of unanswered questions, especially due to
- 93 -
the appearance of a trend favoring the satiating capacity of the
higher-protein intake.
A series of original investigations by Antonio et al112-114,173
spanning 8 weeks to 6 months on resistance-trained subjects
involved baseline protein intakes of ~2.0-2.2 g/kg that were
increased to 3.3-4.4 g/kg with no significant changes in body
composition overall (except one study saw greater
recomposition in the high-protein condition112). It’s
remarkable that in free-living conditions, increasing baseline
protein intakes by approximately 50-100% for months did not
result in significant weight or fat gain. It’s likely that heightened
satiety drive down the intake of the other macronutrients,
since the ‘disappearance’ of the surplus protein calories cannot
all be explained by increased thermogenesis (energy
expenditure).
Summing up
Protein is the king of the macronutrients for satiety. In
hypocaloric conditions, it’s debatable whether 1.8 g/kg (vs 2.9
g/kg) is sufficient to max-out satiety, although there seems to
be an advantage for suppressing cravings and increasing
satisfaction with 2.9 g/kg.172 In the case of protein overfeeding
in resistance trainees, there’s potentially some satiety magic
with intakes at or beyond approximately 3 g/kg.112-114,173
- 94 -
Chapter 26: What about non-linear protein
intake through the week (training days vs nontraining days, protein hyperfeeds)?
Carb-cycling, or non-linear carbohydrate intake through the
course of the week has been a perennial topic at the forefront
of physique and athletic performance pursuits. Less on-theradar is non-linear protein intake through the course of the
week, and how it might benefit body composition goals.
Training days vs. non-training days
A question I’ve been frequently asked is whether protein needs
differ on training versus non-training days. I answer most
questions with a couple of questions of my own: What’s the
goal, and what are the stakes? That’s my way of getting the
people to think about what they want to accomplish, what their
current training &/or body comp status is, and how much is
riding on the attainment of this goal.
There’s a wide range of possible scenarios to consider. To
simplify things for this discussion, we can focus on two general
targets: the goal of maximizing muscle gain, and the goal of
muscle retention while dieting. Maximally facilitating muscle
gain involves sustaining a net caloric surplus.22 Given this, it’s
- 95 -
not typical for people seeking mainly to gain muscle to search
for ways to economize their caloric intake. There is a segment
of the protein research audience concerned with the potential
for high protein intakes to negatively impact longevity.
However, as discussed in Chapter 15, this is a far-fetched idea.
Nevertheless, I’m still regularly asked if it’s necessary or
beneficial to lower protein intake on non-training days. This
would potentially be warranted if the training-induced
elevation in muscle protein turnover (synthesis & breakdown)
was a very short-lived phenomenon. This is not the case.
Protein turnover can stay elevated for 24-48 hours after a bout
of resistance exercise.174-176 Burd et al177 found that
myofibrillar MPS and anabolic signaling were enhanced by
protein feedings for at least 24 hours after a bout of resistance
exercise. Damas et al178 examined muscle protein changes in
the 24-48 post-exercise period, and found that muscle
hypertrophy occurs via gains in myofibrillar MPS mainly after
the attenuation (lowering) of muscle damage. This reinforces
the importance of optimizing dietary protein intake to
maintain positive net balance of muscle protein turnover.
The main message here is that enhanced muscle sensitivity and
receptivity to protein/amino acids persists far beyond the
immediate post-exercise period, and well into the following
- 96 -
day (and possibly beyond). Thus, for the goal of maximal
utilization of protein during the 24-48-hour recovery period
where pushing for positive net protein balance is crucial for
muscle growth, low-balling protein intake during non-training
days is a bad idea.
The what, why, & how of protein hyperfeeds
“Protein hyperfeed” is a cool-sounding term I came up with. It’s
the protein equivalent of a carb-up without the low intake part
of the cycle. While carb refeeds are large bouts of carb intake
alternated with carb restriction of varying severity, protein
hyperfeeds are high-protein days (2-2.5 times the normal
intake) placed strategically through the week. “Normal”
protein intake would actually be defined as what’s optimal in
normal circumstances (≥1.6 g/kg per day). Hyperfeeds would
put protein at approximately 3.2-4.5 g/kg, or 1.45-2.0 g/lb for
the day. For example, a 75 kg person might consume 135 g
protein on a normal day. A hyperfeed day would provide 2-2.5
times this amount, which is 270-337 g.
There are three main uses/objectives for protein hyperfeeds
that can be pursued separately or in combination, depending
on the individual’s goals and current training status: 1) to
maximize satiety and minimize cravings in general, and
- 97 -
especially on carb-restricted days, 2) to allow bouts of ad
libitum/unrestricted eating for the purpose of alleviating
psychological “diet fatigue” with minimal risk for undue fat
gain, and 3) to push toward recomposition in higherintermediates and advanced trainees. This third point is more
of a dice-roll. Nevertheless, in my observations, even when
protein hyperfeeds are calculated as net surplus calories, there
is still a “disappearance” of the extra protein, as reported
repeatedly by Antonio et al,112-114,173 whose subjects saw either
no significant change, or favorable change in body composition
(fat loss and/or muscle gain) as a result of no other program
change aside from increasing protein intakes to ≥3 g/kg.
Potential explanations for Antonio et al’s “disappearing”
protein surpluses include increased thermogenesis (both
dietary, exercise-based, and non-exercise-based), increased
satiety driving down the intake of the other macronutrients,
misreporting of intake, and increased excretory energy
losses.33
I witnessed this type of protein-induced recomp in clients
several years before Antonio et al’s protein overfeeding
studies, so while some viewed the findings with skepticism,
they actually reflected my notes from the trenches. In eucaloric
(maintenance) conditions, and even in purposefully targeted
- 98 -
net weekly surplus conditions, I have observed recomp in
clients on regular protein hyperfeeds. There are a multitude of
variables that make recomp possible,44 but in my observations,
experimenting with protein hyperfeeds through the week is a
tool worth trying out for this purpose.
In my experience and observations in clients, 2-3 protein
hyperfeeds per week is what most people can tolerate (and
enjoy). Protein hyperfeeds should ideally be positioned on, or
immediately before days where cravings are historically
highest for the individual. Or, choose any day(s) where
carbohydrate intake is not elevated for refeeding or carbing-up.
An interesting phenomenon I’ve observed repeatedly is that
the satiating effects of the protein hyperfeed can last through
the entire following day. Individual responses vary here.
Summing up
• Rather than low-balling protein on days off, it’s best to keep
protein at levels known to optimize adaptations to resistance
training. Protein turnover and heightened muscular
sensitivity to protein feeding can last 24-48 hours after a
training bout.
• Protein hyperfeeds are a tool I’ve used with dieters seeking
novel tactics to increase satiety and minimize the
- 99 -
psychological fatigue of dieting. It has also worked for
intermediate and advanced trainees seeking recomposition.
• My field experience with protein hyperfeeds reflects the
intriguing results of Antonio et al’s protein overfeeding
studies,112-114,173 as well as Bararat et al’s recent review
reporting that a protein intake of 2.6-3.5 g/kg of FFM is
associated with recomposition.44 The protein hyperfeed
protocol I’ve found success with involves 2-2.5 times normal
protein intake, 2-3 days per week. Protein sources should be
kept lean, for the most part.
• Protein hyperfeeds also make protein lovers extremely
excited about their diets - especially those who prefer more
savory foods than sweet foods. Those with more of a sweet
tooth can still engage in protein hyperfeeds, since endless
dessert variants can be derived from protein powder.
• Who knows, maybe there’s some metabolic magic to be had
from protein hyperfeeds. We’ve got the insulin fairy, might as
well add the protein fairy to the mix (to my newer readers
who might not get that, it’s a corny inside-joke for those who
have been following my work since the olden days).
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Chapter 27: Protein servings & sources
Categorizing foods is a messy endeavor since there’s inevitable
overlap in macronutrition and micronutrition. Nevertheless, a
general awareness of the fat levels of your protein sources can
help you make the right choices based on the nature of the
overall macronutrient profile you’re aiming for.
A note about the listed macronutrient values of each food: they
almost never add up exactly to the total calories per serving.
This is an unavoidable shortcoming. I used nutritiondata.com,
for the most part. It relies on the USDA's National Nutrient
Database. Even the most sophisticated and reliable databases
are unable to list nutrient stats with complete accuracy. This is
partially due to the necessity of rounding off values. However,
the important thing is that the numbers are close enough.
Thinking you’ll hit everything perfect down to the gram is not
just unrealistic, it’s also an unnecessary level of micromanagement that will not make or break anyone’s results.
The following food lists are separated into animal and plantbased sources. Leucine content is included. With few
exceptions such as protein powder, plant-based protein
sources have a lower proportion of protein and higher
proportion of carbohydrate and/or fat, so they pack less
protein per calorie.
- 101 -
Remember that serving sizes are arbitrary (& adjustable)
I listed serving sizes that (for the most part) hit 20 g protein or
more. You’ll notice that many of the plant-based servings come
up shy of 20 g protein. However, you can adjust all of the
serving sizes (or number of servings) up or down to hit a
particular protein dose. Just be aware of how serving
adjustments impact total calories. On a final note, keep in mind
that this is not a comprehensive list of foods. The aim is to give
you a quick reference, and help you get some ideas.
VERY LEAN PROTEIN SOURCES: ANIMAL-BASED
Food
Serving
size
Beef, ground, 95% lean
3.5 oz
meat
(100 g)
Beef, top sirloin, separable 3.5 oz
lean only, trimmed to 0"
(100 g)
fat, select, cooked, broiled
Casein protein powder
1 scoop
(combination of micellar
(32 g)
casein and milk protein
concentrate),
Catfish, cooked, dry heat
3.5 oz
(100 g)
Cheese, cottage, 2%
1 cup
milkfat
(238 g)
Cheese, low-fat, cheddar
2/3 cup,
or colby
shredded
(75 g)
Chicken breast, meat only, 3.5 oz
roasted
(100 g)
kcal
171
Prot
(g)
26.3
Carb
(g)
0
Fat
(g)
6.5
Leu
(g)
2.0
177
30.8
0
5.0
2.5
120
24.0
5.0
1.0
2.0
105
18.5
0
2.8
1.5
180
22.0
6.0
5.0
2.2
129
18.1
1.5
5.2
1.8
165
31.0
0
3.6
2.3
- 102 -
VERY LEAN PROTEIN SOURCES: ANIMAL-BASED
Food
Clam, mixed species,
cooked, moist heat
Cod, Atlantic, cooked, dry
heat
Egg whites, raw, fresh
Orange roughy, cooked,
dry heat
Pork, fresh, loin,
tenderloin, fat-trimmed,
roasted
Salmon, canned, solids
with bone and liquid
Sea bass, mixed species,
cooked, dry heat
Shrimp, mixed species,
cooked, moist heat
Snapper, mixed species,
cooked, dry heat
Tuna, light, canned in
water, drained solids
Turkey breast, skinless,
cooked, roasted
Trout, rainbow, cooked,
dry heat
Whey protein powder (mix
of isolate and concentrate)
Whitefish, mixed species,
cooked, dry heat
Yogurt, Greek style, nonfat
Serving
size
3.5 oz
(100 g)
3.5 oz
(100 g)
1 cup or
8-12
whites
(243 g)
3.5 oz
(100 g)
3.5 oz
(100 g)
kcal
148
Prot
(g)
25.5
Carb
(g)
5.1
Fat
(g)
1.9
Leu
(g)
1.8
105
22.8
0
0.9
1.8
117
26.5
1.8
0.4
2.5
105
22.6
0
0.9
1.8
143
26.2
0
3.5
2.2
3.5 oz
(100 g)
3.5 oz
(100 g)
3.5 oz
(100 g)
3.5 oz
(100 g)
3.5 oz
(100 g)
3.5 oz
(100 g)
3.5 oz
(100 g)
1 scoop
(32 g)
3.5 oz
(100 g)
1 cup
(224 g)
139
19.8
0
6.1
1.6
124
23.6
0
2.6
1.9
99
20.9
0
1.1
1.7
128
26.3
0
1.7
2.1
116
25.5
0
0.8
2.1
135
30.1
0
0.7
2.4
169
24.3
0
7.2
1.9
120
24.0
3.0
1.5
2.5
172
24.5
0
7.5
2.0
120
20.0
9.0
0
1.6
- 103 -
LEAN TO MODERATE-FAT PROTEIN SOURCES: ANIMAL-BASED
Food
Serving
size
3.5 oz
(100 g)
3.5 oz
(100 g)
kcal
2/3 cup
(150 g)
Cheese, mozzarella, part
3.5 oz
skim milk
(100 g)
Cheese, ricotta, part skim 2/3 cup
milk
(162 g)
Chicken, leg, meat and
3.5 oz
skin, roasted
(100 g)
Duck, domesticated, meat 3.5 oz
only, cooked, roasted
(100 g)
Egg, whole, hard-boiled or 3 large
poached
(150 g)
Lamb, foreshank, trimmed 3.5 oz
to 1/8" fat, braised
(100 g)
Pork, fresh, loin, center rib 3.5 oz
(chops), bone-in, separable (100 g)
lean and fat, braised
Salmon, Atlantic, cooked, 3.5 oz
dry heat
(100 g)
Sardines, canned in tomato 3.5 oz
sauce, drained solids with (100 g)
bone
Turkey sausage, fresh,
3.5 oz
cooked
(100 g)
Beef, ground sirloin, 90%
lean meat
Beef, ground, 85% lean
meat/15% fat, patty,
broiled
Cheese, feta, reduced fat
214
Prot
(g)
26.6
Carb
(g)
0
Fat
(g)
11.1
Leu
(g)
2.0
250
25.9
0
15.5
2.0
206
21.0
0
13.0
1.7
254
24.3
2.8
15.9
2.4
224
18.5
8.3
12.9
2.0
232
26.0
0
13.5
1.9
201
23.5
0
11.2
2.0
232
18.9
1.8
15.9
1.6
243
28.4
0
13.5
2.2
250
26.7
0
15.1
2.1
206
22.1
0
12.3
1.8
186
20.9
0.7
10.5
1.4
196
23.9
0
10.4
1.7
- 104 -
HIGH-FAT PROTEIN SOURCES: ANIMAL-BASED
Food
Serving
size
Bacon
2 oz
(56 g)
Beef, corned beef, brisket,
3.5 oz
cooked
(100 g)
Beef sausage, fresh, cooked 3.5 oz
(100 g)
Beef tongue, cooked
3.5 oz
(100 g)
Cheese, American
3 oz
(85 g)
Cheese, blue
3 oz
(85 g)
Cheese, cheddar
2/3 cup,
(75 g)
Cheese, feta
1 cup
(150 g)
Cheese, goat
3 oz
(85 g)
Cheese, Monterey jack
3 oz
(85 g)
Cheese, Swiss
3 oz
(85 g)
Sausage, beef, fresh, cooked 3.5 oz
(100 g)
Sausage. pork, fresh, cooked 3.5 oz
(100 g)
kcal
298
Prot
(g)
21.4
Carb
(g)
0.8
Fat
(g)
22.6
Leu
(g)
1.7
251
18.2
0
19.0
1.4
332
18.2
0
28.0
1.5
284
19.3
0
22.3
2.0
315
18.6
1.2
26.4
1.6
297
18.0
2.1
24.0
1.6
300
18.5
0.9
24.8
1.6
396
21.3
0
31.9
1.7
381
25.5
1.8
30.0
2.1
300
21.0
1.0
27.0
1.6
318
22.5
4.5
23.4
1.8
332
18.2
0.4
28.0
1.5
339
19.4
0
28.4
1.3
- 105 -
VERY LEAN PROTEIN SOURCES: PLANT-BASED
Food
Beans, black, cooked
Beans, kidney, all types,
cooked
Beans, lima, large, cooked
Beans, navy, cooked
Beans, pinto, cooked
Beans, white, cooked
Beans, refried, canned
Serving
size
1 cup
(172 g)
kcal
1 cup
(177 g)
1 cup
(188 g)
1 cup
(182 g)
1 cup
(171 g)
1 cup
(179 g)
1 cup
(238 g)
1 cup
(164 g)
1 cup
(172 g)
Chickpeas (garbanzo beans,
cooked
Cowpeas, common
(blackeyes, crowder,
southern), cooked
Edamame (soybean), frozen, 1 cup
prepared
(155 g)
Lentils, cooked
1 cup
(198 g)
Peas, green, cooked, boiled, 1.5 cups
drained
(240 g)
Pea protein isolate
1 scoop
(28 g)
Soy protein isolate
1 scoop
(28 g)
Veggie burgers or soy
2 patties
burgers
(140 g
total)
227
Prot
(g)
15.2
Carb
(g)
40.8
Fat
(g)
0.9
Leu
(g)
1.2
225
15.3
40.4
0.9
1.3
216
14.7
39.3
0.7
1.3
255
15.0
47.8
1.1
1.3
245
15.4
44.8
1.1
1.1
249
17.4
44.9
0.6
1.4
217
12.9
36.3
2.8
1.0
269
14.5
45.0
4.2
1.0
200
13.3
35.7
0.9
1.0
189
16.9
15.8
8.1
1.2
230
17.9
39.9
0.8
1.3
187
12.3
34.2
0.6
0.7
110
23.1
1.7
1.7
1.9
94.6
22.6
2.1
0.9
1.9
248
22.0
20.0
8.8
1.9
- 106 -
LEAN TO MODERATE-FAT PROTEIN SOURCES: PLANT-BASED
Food
Serving
size
Falafel
3.5 oz
(100g),
Hummus
2/3 cup
(162 g)
Soybeans, roasted (soy nuts) 1/3 cup
(57g)
Tempeh, cooked
3.5 oz
(100 g)
Tofu, firm
1 cup
(252 g)
kcal
333
Prot
(g)
13.3
Carb
(g)
31.8
Fat
(g)
17.8
Leu
(g)
0.9
269
12.8
23.2
15.6
0.9
256
22.4
18.5
12.2
1.8
196
18.2
9.4
11.4
1.4
176
20.6
4.2
10.6
1.8
Carb
(g)
18.0
Fat
(g)
20.5
Leu
(g)
1.4
HIGH-FAT PROTEIN SOURCES: PLANT-BASED
Food
Serving size
kcal
Almonds
542
575
12.5
10.8
58.3
1.0
553
13.9
29.6
41.9
1.2
Chia seeds, whole
2/3 cup, whole
(94 g)
2/3 cup, whole
(88 g)
2/3 cup, whole
(100g)
2/3 cup (100 g)
Prot
(g)
20.0
490
15.6
43.8
30.8
1.3
Flaxseed, whole
2/3 cup (111 g)
592
20.3
32.0
46.7
1.4
Hazelnuts
2/3 cup (76 g)
477
11.3
12.7
46.1
0.8
Peanuts
2/3 cup (96 g)
564
22.8
20.7
47.8
1.5
Pistachios
2/3 cup (81 g)
463
17.4
22.4
37.3
1.3
Pumpkin or squash
seeds, unshelled
Sunflower seed
kernels, dry roasted
2/3 cup (91g)
493
22.4
16.2
41.8
1.9
2/3 cup (84 g)
492
16.3
20.3
42.1
1.2
Brazil nuts
Cashews
- 107 -
Postscript
Congrats, you made it! For those who finished the book and have
questions, suggestions, criticisms, or compliments, feel free to
email me: alaneats@gmail.com. Your feedback is muchappreciated, and will be helpful for improving future editions.
This book is a free gift for current AARR subscribers. For those
who are not yet subbed, but want to stay on top of the latest
research (with instant access to the archive of monthly content
dating back to 2008), go here: https://alanaragon.com/aarr
Thanks & all the best,
– Alan
- 108 -
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___________________________________________________________________________________________________
This is the end of the book, but the beginning of an adventure.
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