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COMPARISON OF SHORT-TERM HYPOCALORIC HIGH PROTEIN
DIETS WITH A HYPOCALORIC MEDITERRANEAN DIET: EFFECT
ON BODY COMPOSITION AND HEALTH-RELATED BLOOD
MARKERS OF OVERWEIGHT AND SEDENTARY YOUNG
PARTICIPANTS
Konstantinos Feidantsis , Spyridon Methenitis ,
Kleopatra Ketselidi , Kiriaki Vagianou , Petros Skepastianos ,
Apostolos Hatzitolios , Alexandros Mourouglakis , Athina Kaprara ,
Maria Hassapidou , Tzortzis Nomikos , Sousana K. Papadopoulou
PII:
DOI:
Reference:
S0899-9007(21)00227-6
https://doi.org/10.1016/j.nut.2021.111365
NUT 111365
To appear in:
Nutrition
Received date:
Revised date:
Accepted date:
18 January 2021
11 April 2021
27 May 2021
Please cite this article as: Konstantinos Feidantsis , Spyridon Methenitis , Kleopatra Ketselidi ,
Kiriaki Vagianou ,
Petros Skepastianos ,
Apostolos Hatzitolios ,
Alexandros Mourouglakis ,
Athina Kaprara , Maria Hassapidou , Tzortzis Nomikos , Sousana K. Papadopoulou , COMPARISON OF SHORT-TERM HYPOCALORIC HIGH PROTEIN DIETS WITH A HYPOCALORIC
MEDITERRANEAN DIET: EFFECT ON BODY COMPOSITION AND HEALTH-RELATED BLOOD
MARKERS OF OVERWEIGHT AND SEDENTARY YOUNG PARTICIPANTS, Nutrition (2021), doi:
https://doi.org/10.1016/j.nut.2021.111365
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1
Highlights
2

Hypocaloric MD provides all the necessary nutrients
3

Hypocaloric MD reduces body mass, fat mass and maintains FFM
4

Hypocaloric MD: beneficial on metabolic and inflammation/muscle damage
5
indices
6

Hypocaloric HP / HPW reduce body mass and FFM, but not fat mass
7

Hypocaloric HP / HPW: adverse on metabolic and inflammation/muscle damage
8
indices
9
1
10
11
COMPARISON OF SHORT-TERM HYPOCALORIC HIGH PROTEIN DIETS
12
WITH A HYPOCALORIC MEDITERRANEAN DIET: EFFECT ON BODY
13
COMPOSITION AND HEALTH-RELATED BLOOD MARKERS OF
14
OVERWEIGHT AND SEDENTARY YOUNG PARTICIPANTS
15
16
Running Title: Hypocaloric Mediterranean and high-protein diets
17
1,2
*, Spyridon Methenitis
1,3
18
Konstantinos Feidantsis
19
Kiriaki Vagianou
20
Mourouglakis 5, Athina Kaprara 6, Maria Hassapidou 1, Tzortzis Nomikos
21
Sousana K. Papadopoulou 1
22
*Authors with equal contribution and should consider as both first authors
1,7
*, Kleopatra Ketselidi
1,7
,
, Petros Skepastianos 4, Apostolos Hatzitolios 5, Alexandros
7
&
23
1. Department of Nutrition Sciences and Dietetics, Faculty of Health Sciences,
24
International Hellenic University, P.O.Box 141, 574 00, Sindos, Thessaloniki,
25
Greece
26
27
28
29
30
31
2. Laboratory of Animal Physiology, Department of Biology, Aristotle University of
Thessaloniki, GR 54124, Thessaloniki, Greece
3. Sports Performance Laboratory, School of Physical Education & Sports Science,
National and Kapodistrian University of Athens, Athens, Greece
4. Department of Biomedical Sciences, Faculty of Health Sciences, International
Hellenic University, Sindos Thessaloniki Greece
32
5. Diabetes Center, EASO Obesity Center, First Propedeutic Department of Internal
33
Medicine, Medical School, Aristotle University of Thessaloniki, AHEPA
34
Hospital, Thessaloniki, Greece
35
36
37
38
6. Laboratory of Sports Med, School of Physical Education and Sports
Science, Thessaloniki, Aristotle University of Thessaloniki, Greece
7. Department of Nutrition and Dietetics, School of Health Science & Education,
Harokopio University of Athens, Athens, Greece
39
2
40
Correspondence: Konstantinos Feidantsis (), email: kfeidant@bio.auth.gr, Tel:
41
00302310998413
42
Abstract
43
The aim of the present study was to compare the short-term effects of hypocaloric
44
Mediterranean and two high protein diets, with and without whey protein
45
supplementation, on body composition, lipidemic profile, inflammation and muscle
46
damage blood indices, in overweight, sedentary, young participants. Thirty-three young,
47
overweight, male and female participants (Age: 22.8±4.8 yrs, Body Mass: 85.5±10.2 kg,
48
Body Fat Percentage: 34.3±8.1%) were randomly allocated to three different hypocaloric
49
(-700 kcal·day-1) diets: (A) Mediterranean Diet (MD; n=10), (B) High Protein (HP; n=10)
50
diet, and (C) High Protein - Whey Supplementation (HPW; n=10) diet. The intervention
51
lasted 6 weeks. Body composition and biochemical indices were evaluated 1 week before
52
and after the nutritional interventions. Body and fat mass were decreased in MD and HP
53
group (p<0.05; -1.7±1.2% - -7.3±4.2%), while no significant decline of fat free mass
54
(FFM) was observed in the MD group. The MD diet beneficially altered the lipid profile
55
(p<0.05) while the HP and HPW diets did not induce significant changes. Subclinical
56
inflammation and muscle damage indices were significantly increased in HP and HPW
57
groups (p<0.05; 7.4±3.5% - 266.6±55.1%), but were decreased in MD group (p<0.05; -
58
33.3±10.1% - 1.8±1.2%). Energy intake of carbohydrates and proteins was significantly
59
related to the changes of body composition and examined biochemical blood markers
60
(p<0.05; r: -0.389 -0.889). Among the three hypocaloric diets, only the MD diet induced
61
positive changes in body composition and the metabolic profile of overweight, sedentary
62
individuals.
63
3
64
Graphical abstract
65
66
67
Keywords: protein supplementation; fat free mass; blood indices; inflammation; obesity
68
Introduction
69
While obesity is closely related to inflammation, oxidative stress, glucose
70
intolerance, metabolic and cardiovascular diseases, with a negative impact on health and
71
health care economics [1, 2, 3], its prevalence arises each year in the developed countries.
72
Thus, scientists investigate the effect of several lifestyle interventions, including energy-
73
restricted diets and exercise, on body weight/fat loss and obesity’s comorbidities.
74
Caloric restriction diets (hypocaloric diets 500-800 kcals·day-1) [4], including
75
hypocaloric Mediterranean Diet (MD) seem to beneficially affect increased body
76
weight/fat [5]. However, an undesired consequence of the negative energy balance is fat
77
free mass (FFM) significant reduction (~25%) [6]. FFM reduction is linked with
78
decreased basal metabolic rate, a down-regulation of muscle protein synthesis and
79
upregulation of muscle protein degradation, thus jeopardizing short and long term
80
benefits of weight reduction. Reduced FFM also increases the risk for the development of
81
several chronic diseases, such as metabolic syndrome and type II diabetes [6, 7, 8, 9, 10].
82
In recent years, “high protein diets” with additional (beyond Recommended
83
Dietary Allowance - RDA) protein intake, although hypocaloric, are very promising for
4
84
FFM maintenance in athletes and trained individuals. These diets seem to have a direct
85
positive impact on several biological mechanisms, including satiety and energy
86
expenditure increase [e.g. 11, 12, 13]. However, their effects especially in obese or
87
individuals with type II diabetes body composition are discrepant and controversial [14],
88
mostly regarding the lipidemic profile [15], liver and kidney function [16]. Several
89
studies showed that increased amino acids (AA) levels in blood plasma due high protein
90
diets have been linked with increased odds for hyperinsulinaemia, insulin resistance and
91
type II diabetes [17, 18]. In addition, high protein consumption has been linked to
92
increased inflammation and to liver and kidney dysfunction due to an increase of uric
93
acid, an end-product of purine metabolism. On the other hand, isocaloric or hypocaloric
94
Mediterranean Diets (MDs) induce beneficial changes on lipidemic profile and several
95
cardiometabolic risk factors [19, 20, 21].
96
According to the above, the aim of the present study was to compare the short-
97
term effects of hypocaloric Mediterranean MD and two high protein diets, with and
98
without whey protein supplementation (HPW and HP respectively), on body
99
composition, lipidemic profile, inflammation and muscle damage blood indices, in
100
overweight, sedentary, young participants.
101
102
Methods
103
Nutritional Interventions
104
In an effort to evaluate the short-term effect of MD, HPW and HP diets on body
105
composition, lipidemic profile, inflammation and muscle damage blood indices, in
106
overweight, young, sedentary participants, a 6 week intervention period was selected,
107
according to previous reports [22, 23, 24]. Every week, each one of the participants met
108
with one of the nutritionists of our research team, in order to receive her/his new dietary
109
plan, as well as to discuss possible queries that might affect the results of the study, as
110
well as to verify her/his commitment. Individualized diets were designed weekly for each
111
participant, considering their daily energy expenditure, their resting metabolic rate
112
(RMR) (already evaluated before the intervention), as well as their eating habits and their
113
needs in macro and micronutrients components. For weight loss facilitation, all diets were
114
hypocaloric, aiming to induce a moderately negative energy balance of approximately
5
115
600-700 kcal·day-1 [4]. The nutritional plan included 3 meals and 2 snacks per day. In
116
addition, all diets provided the same caloric intake per day. A detailed presentation of the
117
three nutritional interventions is presented in Table 1. In the MD group, each participant
118
followed a standard hypocaloric MD (Table 1), based on the principles of the
119
Mediterranean Diet, consisting of 58.39±2.12% carbohydrates, 27.95±1.57% fats and
120
15.87±0.49% proteins per day (1.5 g·kg FFM-1·day-1). In both HP and HPW groups, the
121
daily protein intake was set at 2.5 g·kg FFM-1·day-1, in order to protect FFM losses
122
during caloric restricted diets [25]. The calculation of the protein intakes per kg FFM
123
instead of per kg of body mass was selected, because FFM is more metabolically active
124
compared to fat tissue [25] . In addition, protein intake per meal did not exceed 20-30 g,
125
in both HP and HPW groups, as previously proposed [26]. Accordingly, HP and HPW
126
diets consisted of 43.6±2.3% and 44.1±2.3% carbohydrates, 27.4±0.9% and 27.2±0.9%
127
fats, 28.7±1.9% and 28.9±1.4% proteins, respectively (Table 1; no significant differences
128
between HP and HPW groups, p>0.05). The HP and HPW interventions differed only in
129
the dietary source of protein. Specifically, in the HP group, protein was exclusively
130
obtained from food, while in the HPW group, 50% of the daily protein intake was
131
obtained from a whey protein supplement (isolated whey protein formula provided by
132
BioMax BioWhey), in which 25 g consisted of 102 kcal, 1.9 g carbohydrates, 0.6 g fats,
133
and 21 g proteins of which 5 g were branched chain amino acids (BCAA) and 5 g were
134
glutamine.
135
136
All participants, recorded their dietary intake for three consecutive days, two
137
weekdays and one weekend day. An experienced dietitian provided verbal and written
138
instructions for food diaries completion. Food models were used for the estimation of
139
consumed foods’ quantity. Food diaries’ analysis was performed by experienced
140
dietitians via the Food Processor Program (version 7.4, ESHA Research Salem, Oregon)
141
with the inclusion of traditional Greek recipes [9, 27]. The validity and reliability of the
142
used questionnaire have been evaluated in previous studies of our lab [9, 27], and the
143
Intraclass Correlation Coefficient (ICC) ranged from 0.850 to 0.901 (95% CI: Lower =
144
0.80, Upper = 0.92).
145
6
146
Experimental Approach to the Problem
147
Participants were recruited via advertisements in local university-student
148
societies. Those who fulfilled the following inclusion criteria: 1) Body mass index (BMI)
149
> 25 Kg·m-2, 2) absence of systematic exercise training during the previous 12 months
150
and the intervention period 3) weight stability (±2 kg) at least for three months prior to
151
the entrance in the study, 4) absence of metabolic, cardiovascular and/or pulmonary
152
diseases, (5) no supplement consumption, (6) no additional dietary plan for weight loss or
153
maintenance, and 7) age range 18 - 25 years, visited the laboratory for a second time for
154
medical examination and body composition evaluation by bioelectrical impedance
155
analysis (BIA). RMR was evaluated through indirect calorimetry. A completion of a 3-
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day recall questionnaire, after detailed oral and written explanations, was employed for
157
the assessment of the participants’ dietary habits and physical activity. Each participant
158
was assigned into one of the 3 groups: 1) MD 2) HP and 3) HPW. One week later,
159
participants started their 6-weeks nutritional intervention. During the study, dietary intake
160
and weekly physical activity were evaluated by questionnaires at intervals of 2, 4 and 6
161
weeks, in order to evaluate the compliance to the prescribed dietary schemes. One week
162
after the end of the nutritional intervention, body composition and RMR were re-
163
evaluated, while a second venous blood sample was obtained, after an overnight fast.
164
165
Participants
166
After the initial screening of responders, thirty-three young male (17) and female
167
(16), Caucasian, overweight volunteers, fulfilling the inclusion criteria, provided their
168
written consent to participate in the study. Three participants (one from each group) were
169
excluded from the study. Thus, 30 participants finished the experimental procedure. After
170
the initial evaluations all responders were assigned into 3 groups (each group consisted of
171
5 males and 5 females participants), according to their body fat percentage and fat free
172
mass (FFM; no differences between the groups; p>0.05): (A) MD (n=10; Age: 21.40±2.9
173
yrs, Body Mass: 84.1±8.7 kg, Body Height: 174.20±4.58 cm, Body Fat Percentage:
174
33.0±7.8%), (B) HP (n=10; Age: 23.2±3.1 yrs, Body Mass: 86.7±7.9 kg, Body Height:
175
177.20±5.08 cm, Body Fat Percentage: 34.3±8.1%) and (C) HPW (n=10; Age: 23.10±4.3
176
yrs, Body Mass: 85.7±7.2 kg, Body Height: 175.99±8.12 cm, Body Fat Percentage:
7
177
35.5±9.1%). The initial descriptive characteristics of participants’ body composition in
178
each group are presented in Table 2. All procedures were in accordance with the
179
Declaration of Helsinki and approved by the local university ethics committee, while all
180
participants signed an informed consent before entering in the research procedure.
181
182
Evaluation of Physical Activity, Energy expenditures and Resting Metabolic Rate.
183
Physical activity was recorded via three self-reported questionnaires (2 weekdays
184
and one weekend day) in order to determine participants’ level of physical activity,
185
frequency and duration per day (ICC = 0.95, 95% CI: Lower = 0.90, Upper = 0.98; p <
186
0.0001, n=10) [9, 27, 28], both before the initiation and during the study. Revised tables
187
by Ainsworth et al. [29] were used to estimate the energy cost of each activity. RMR was
188
evaluated through indirect calorimetry (FitMate pro, COSMED, Rome, Italy). The ICCs
189
for this evaluation have been explored in a pilot study from our laboratory, and was 0.897
190
(95% CI: Lower = 0.85, Upper = 0.94; p < 0.0001, n=10).
191
192
Evaluation of body composition and anthropometric characteristics.
193
Height was measured using a stadiometer (SECA 220, Seca Corporation,
194
Columbia, USA), while body mass using a calibrated digital scale (Seca 707, Seca
195
Corporation, Columbia, USA). Body composition was evaluated via BIA (50Hz;
196
Bodystat 1500, Bodystat Ltd) and measurements were analyzed using Bodystat 1500
197
computer software, with the use of specific equations for Caucasian males and females
198
participants (Bodystat 1500 Body Manager, version3.16, 2002, Bodystat Ltd). BIA
199
evaluation was performed according to previous recommendations for the estimation of
200
body fat (percentage and Kg), FFM (percentage and Kg) and total body water (%;
201
bioelectrical impedance vector analysis) according to the manufacture instructions [ICC
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for body fat = 0.93, (95% CI: Lower = 0.89, Upper = 0.97), LBM =0.98, (95% CI: Lower
203
= 0.95, Upper = 0.99), water = 0.94, (95% CI: Lower = 0.88, Upper = 0.98), p < 0.0001,
204
n = 10] [24].
205
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Blood sampling and biochemical assays.
8
207
Venous blood samples were obtained from each subject, after at least 8 hours of
208
fasting, during morning hours (8:00-9:00 am). Complete blood count was determined in
209
EDTA anticoagulated whole blood sample on a Mindray BC-3000 hematology analyzer
210
(Mindray, Shenzhen, China). For biochemical parameter determinations, blood samples
211
were drawn in Vacutainer-type tubes containing clot activator and were centrifuged for 30
212
min. The recovered sera were stored at -40˚C until further analysis. All biochemical
213
parameters were measured through a Mindray BS-300 Chemistry Analyzer (Mindray,
214
Shenzhen, China). Blood analysis was performed with respective reagents for each
215
parameter, together with original calibrators with metrological traceability as well as
216
controls for the above analyzer and according to manufacturers instructions. Moreover,
217
appreciable recovery rates (93.96–98.43%) of all the biochemical parameters examined
218
herein, indicated very good compatibility of extraction media for biochemical analysis.
219
220
Statistical Analyses
221
A post hoc power analysis (G*Power ver 3.1; FrankFaul, Universitat Kiel,
222
Germany), which is ideal for social, behavioral and biomedical sciences [30], was
223
performed, according to the study design, the number of participants that completed the
224
protocols and the evaluations, and the lowest Partial Eta Squared of the significant
225
contrasts or the Pearson’s r correlations coefficient that were found. The results of this
226
analysis revealed that the actual power of the present study results for the contrast
227
between the groups is above 0.890, while for the correlation coefficients ranged between
228
0.857 and 0.912. All data are presented as mean and standard deviation (±SD). Partial eta
229
squared could be used as an indicator of effect size, and it could be classified as small
230
(0.01 to 0.059), moderate (0.06 to 0.137) and large (≥0.138). One-Way and Two-way
231
repeated analysis of variance (ANOVA) followed by Bonferroni Post-Hoc (p ≤ 0.05 was
232
used as a 2-tailed level of significance), and Pearson’s product moment correlation
233
coefficient were used for the investigation of differences and correlations between the
234
groups (SPSS Statistics Ver. 20). The interpretation of the observed correlations was
235
performed according to Hopkins’ ranking: correlations coefficients between 0.3 - 0.5
236
were considered moderate, between 0.51 - 0.70 large, between 0.71 - 0.90 very large, and
237
> 0.91 almost perfect.
9
238
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Results
240
241
242
No significant differences were found between the groups for the initial
243
evaluations of body composition, RMR and biochemical indices (p>0.05; Table 2). As it
244
was expected the participants of HP and HPW groups consumed lower amounts of
245
carbohydrates but higher amount of proteins compared to the MD participants, as it has
246
been designed (p<0.001; Table 2). The two protein groups did not differ in the protein,
247
carbohydrate and fat intake (p>0.05).
248
Significant body mass, BMI and body fat percentages reductions were observed
249
for the MD and HP groups after the hypocaloric diets (p<0.05; factor Time η2: 0.453 –
250
0.747; Table 2). No significant differences were found for these parameters in the HPW
251
group. A significant time x group interaction was found for the body composition
252
variables (p<0.05; Time x Group Interaction η2: 0.262-0.394). Specifically, the MD
253
group presented higher body mass, BMI and body fat percentage decreases (p<0.001)
254
compared to HP and HPW groups (Table 2). FFM decreased in HP and HPW groups,
255
with HPW achieving the highest decrease. MD group participants had no significant FFM
256
loss. Βody fat percentage differed significantly between HP and HPW, with the HP group
257
achieving higher loss (p<0.001). No significant changes were found for RMR between
258
the groups at any time point (p>0.05; η2: 0.050 – 0.079). However, when the percentage
259
changes were taken into account, it was observed that the HPW group showed the highest
260
RMR reduction (-8.9±2.8%), followed by the HP group (-4.6±2.7%), while the MD
261
group showed a minor, non-significant, increase (1.4±0.9%).
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Τable 3 depicts blood indices changes evaluated in the present study. Significant
263
beneficial changes were found for triglycerides, total cholesterol (TC), LDL-cholesterol
264
(LDL-C), HDL-cholesterol (HDL-C) and glucose concentrations, mainly after the MD
265
intervention (p<0.01). A significant Time x Group interaction was found for most
266
variables (Table 3). The highest triglycerides, TC and LDL-C reductions and the highest
267
HDL-C increase were exhibited in the MD group (-42.4±15.4% - 18.2±12.9%), followed
268
by HP (-20.4±12.9% - 3.5±3.1%), while the lowest, insignificant changes were observed
10
269
in the HPW group (-8.3±4.4% - 0.5±2.1%). Significant differences between the
270
concentrations as well as the percentage changes of inflammation and muscle damage
271
related blood markers, were found between the groups after the 6week interval (p<0.001;
272
Time η2: 0.159 – 0.607; Time X Group Interaction η2: 0.081 – 0.610; Table 3, Figure 1).
273
The inflammation markers [white blood cells (WBC), C-reactive protein (CRP)] and the
274
muscle damage markers [Creatine kinase (CK), lactate dehydrogenase (LDH)] remained
275
unchanged or significantly decreased in the MD group, while they significantly increased
276
in the HP and HPW groups (Table 3 and Figure 1). Similarly, aspartate transaminase
277
(AST), alanine transaminase (ALT), gamma-glutamyltransferase (γGT), serum albumin
278
(SA) and serum total protein (STP) concentrations were increased only in the HP
279
(4.4±2.1% -33.3±21.4%) and HPW group (13.1±5.5% - 61.0±17.4%) with significant
280
differences between the groups to be found for the post-intervention values (p<0.05;
281
Time η2: 0.199 – 0.457; Time X Group Interaction η2: 0.164 – 0.366; Table 3) as well as
282
for the percentage changes (p<0.001).
283
284
285
When all participants were considered as one group (n=30), significant
286
correlations were found between the daily energy intakes (kcal), and/or the differences of
287
intakes, compared to pre-intervention values, of carbohydrates, proteins and the
288
percentage changes of body composition components, RMR, blood lipids, inflammation
289
and muscle damage related blood markers (p<0.05; Table 4; Figure 1). Specifically,
290
carbohydrate daily energy intake exhibits moderate to large, negative correlations with
291
the percentage changes of body mass, body fat percentage, triglycerides and LDL-C
292
levels (r: -0.389 - 0.600; p<0.05), but large positive relationships with the changes of
293
FFM and RMR (r: 0.889 and 0.599 respectively; p<0.05; Figure 1). In contrast, protein
294
daily energy intake presents a negative correlation with FFM (r: -0.799) and positive
295
correlations with body mass, body fat percentage, triglycerides and LDL-C levels (r:
296
0.389 – 0.518; p<0.05). It must be pointed out though, that due to the fact that all the
297
above parameters decreased after the nutritional interventions, their percentage changes
298
were negative. Thus, when a negative correlation was found, it indicated that participants
299
with higher amounts of carbohydrates or proteins were those with the highest decrease of
11
300
the above parameters, while the positive ones indicated that participants with higher
301
intakes of carbohydrates or proteins were those with the lowest decrease. Large to very
302
large, negative correlations were found between the daily energy intake from
303
carbohydrates and the percentage changes of WBC, Urea (NG), Creatine (Cr), CK, CRP,
304
LDH, uric acid (UA), AST and ALT (r: -0.442 - -0.844; p<0.05; Table 4).
305
Controversially, positive relationships were found between the daily energy intake from
306
proteins and the percentage changes of the above blood indices (r: 0.510 – 0.703;
307
p<0.05). According to these results, the negative relationships between the daily energy
308
intake from carbohydrates and the percentage changes of the blood parameters mentioned
309
above, indicate that participants who receive higher amounts of carbohydrates per day
310
were those who achieved the lowest increases in these parameters, and vice versa for the
311
positive correlations that were found for the protein intake (Figure 2).
312
313
314
315
Discussion
316
Nowadays, it is well described that even in short-term periods almost all types of
317
calorie restriction diets similarly induce body mass reduction [31, 32] which is
318
accompanied by 75% fat mass and 25-30% FFM losses [33]. Although in athletes who
319
undergo systematic heavy training, an increased amount of protein intake (up to 3.4 g·kg
320
FFM-1·day-1) during caloric restriction diets, seems to be very effective in maintaining
321
FFM and performance [e.g. 12, 13, 25, 27], according to the results of the present study,
322
in the absence of any systematic training, increased protein consumption does not seem to
323
have any significant impact on FFM maintenance in sedentary overweight individuals.
324
The results of the present study provide further support to recent meta-analyses [34, 35]
325
indicating that during short term hypocaloric diets (<12 weeks) in non-trained, healthy
326
participants, high protein diets have a small impact on body, fat mass reductions and
327
FFM maintenance compared to normal protein diets. These observations suggest, that
328
during HP and HPW diets, FFM is sacrificed to support hepatic gluconeogenesis
329
production in the expense of the reduced carbohydrate intake [7].
12
330
Increased consumption of protein, especially when a part comes from whey
331
protein supplementation, raises AA plasma concentrations, which has been linked with
332
suppression of endogenous glucose production, reduced glucose uptake from muscle cells
333
and increase of muscle insulin resistance [19, 36]. AA increased availability, by pyruvate
334
dehydrogenase and hexokinase II inhibition, results in increased AA utilization during
335
mitochondrial oxidation, minimizing glucose and free-fatty acids contributions [37, 38].
336
Moreover, it seems that HP and HPW groups may have a negative impact on molecular
337
pathways controlling muscle mass maintenance and/or hypertrophy such as those of
338
AKT/mTOR, which is activated by insulin, postprandial increase of extracellular AA, but
339
also from glucose [7, 11, 39]. AA increased availability, results in strong stimulation of
340
mammalian target of rapamycin complex 1 (mTORC1) and its dowstream targets, such as
341
the ribosomal protein S6 kinase beta 1 (p70S6k), which is known to control muscle
342
protein synthesis [7, 11, 39]. Indeed, it seems that there is almost a linear increase of
343
muscle protein synthesis after ingestion of 20-35 g of protein per meal. However, the
344
over-stimulation of p70S6k can trigger a negative-feedback loop, leading to insulin
345
receptor substrate 1 (IRS1)de-phosphorylation, AKT/mTOR pathway unregulated
346
activity, muscle protein synthesis reduction and muscle mass degradation, and insulin
347
resistance and adipogenesis [11, 18, 40]. The above mechanisms may explain FFM
348
highest reductions, fat mass lowest losses and increased fasting glucose values in the HP
349
and HPW groups [40]. On the other hand, the amount of protein intake of the hypocaloric
350
MD, seems to be enough in order to elicit a positive stimulation of muscle protein
351
synthesis, and thus maintain FFM.
352
The low carbohydrate availability of HP and HPW diets may also explain the
353
significant losses of FFM through muscle protein breakdown up-regulation, probably
354
owed to the hyper-activation of adenosine monophosphate-activated protein kinase
355
(AMPK) [7, 8, 10, 40]. During low carbohydrate availability, AMPK activation results in
356
up-regulation of muscle autophagy mechanisms leading to increased AA release in order
357
to support hepatic gluconeogenesis and prevent hypoglycemia [7, 11, 36, 40]. The above-
358
suggested mechanisms are supported by the results of the present study, in which FFM
359
strong reduction is strongly correlated to an increase of all muscle inflammation/damage,
360
protein degradation and hepatic blood indices. In addition, the present study showed that
13
361
when a part of the daily increased protein consumption comes from whey protein
362
supplementation, known for its high availability of BCAA (especially of leucine) [39],
363
the negative effects on FFM and all the evaluated blood markers are maximized,
364
suggesting that the above proposed mechanisms may have even higher activation [11, 18,
365
40]. In contrast, in hypocaloric MD, where the availability of carbohydrates was higher
366
and the protein intake was similar to RDI, the previous mechanisms might exhibit lower
367
activation [39, 40], restraining FFM losses, augmenting fat losses and improving
368
biochemical profile.
369
According to the present results, HP and HPW diets resulted to almost
370
hyperuricemia levels (≥7mg·dL-1 for men and ≥6mg·dL-1 for women) [41, 42], since uric
371
acid as an end product of purine metabolism [19]. Moreover, increased blood uric acid
372
concentrations are related with muscle inflammatory/damage blood indices such as CK
373
and high-sensitivity CRP [43], as also observed in the present study. Uric acid can also
374
inhibit insulin signaling and promote insulin resistance, increasing risk for cardiovascular
375
diseases, metabolic syndrome and type II diabetes especially in over-weight and obese
376
individuals [19, 41, 42]. Uric acid increased concentrations are also linked to reduced fat
377
utilization (as energy substrate), increased conversion of excess glucose into lipids,
378
mitochondrial dysfunction [19, 42], vascular oxidative stress, endothelial dysfunction,
379
coronary artery disease and atherosclerosis [43, 44]. Considering all the above, it seems
380
that uric acid increased levels may mediate for the unfavorable metabolic effects
381
observed after hypocaloric, HP diets in sedentary overweight individuals, observed in the
382
present study.
383
Finally, our results demonstrated that high protein consumption, in parallel with a
384
hypocaloric diet, may attenuate the beneficial effects of energy restriction on lipid profile.
385
In the HP and especially HPW groups, almost all lipidemic profile markers exhibited the
386
lowest positive changes. An important concern about HP diets, especially those rich in
387
animal protein sources poor in complex carbohydrates such as dietary fibers, is their
388
direct correlation with higher cholesterol, saturated fatty acids intake and higher
389
cardiovascular diseases risk [45]. Our findings support researches and meta-analyses [46,
390
47] exhibiting a stronger decrease in TG, LDL-C, HDL-C and no significant effect on
391
surrogate cardiovascular disease outcomes such as blood pressure, TC, LDL-C and CRP
14
392
after low protein and high carbohydrate diet. Thus, this type of hypocaloric diets, in
393
sedentary participants cannot minimize the risks for cardiovascular and metabolic
394
diseases. On the contrary, several studies [e.g. 34, 45] have reported an improvement in
395
TG, TC and LDL-C serum levels when replacing dietary CHO content with PRO.
396
Nonetheless, long-term variations of HP diet on lipid profiles warrant further
397
investigation.
398
Unfortunately, there are some limitations in this study that require consideration.
399
First, our sample of overweight individuals cannot generalize our findings to the general
400
population. However, the results of the present study can be a useful tool for future
401
studies of this kind in order to better establish the association of different dietary
402
intervetions with body and other biochemical indexes, in larger samples which are more
403
coherent to the general population. Second, non compliance, self-reported data,
404
measurement errors and bias of food records could have an impact. Third, due to
405
equipment failure, physical activity could not be evaluated through accelerometer devices
406
but was recorded via recall self-reported questionnaire.
407
The results of the present study suggest that in sedentary overweight individuals,
408
a short-term hypocaloric MD seems to provide all the necessary nutrients that are
409
required to induce significant body and fat mass reductions, with FFM concomitant
410
maintenance, moreover inducing positive changes on lipidemic-glucose profile, hepatic
411
and inflammation/muscle damage related blood indices. Thus, it lowers the risks for
412
chronic metabolic and cardiovascular diseases. In contrast, at least in non-trained
413
overweight individuals, HP and HPW reduced body mass, however favoring the
414
reduction of FFM and not of fat mass, while they have negative effects on lipidemic
415
profile and on health/inflammation/muscle damage blood markers. Particularly, these
416
type of diets also increase uric acid blood concentrations, changes which are related to
417
increased risk for insulin resistance, metabolic syndrome and cardiovascular diseases
418
(Figure 3). Thus, hypocaloric high protein diets, especially with whey protein
419
supplementation, should be avoided, during short-term caloric restriction periods, in non-
420
trained overweight men and women.
421
422
15
423
Approval
424
All procedures were in accordance with the Declaration of Helsinki and approved by the
425
Department of Nutrition Sciences and Dietetics, Faculty of Health Sciences, International
426
Hellenic University, Research Ethics Committee (ref. number 1014/2018), while all
427
participants signed an informed consent before entering the research procedure.
428
429
Authors’ Contribution
430
KF and SM performed part of experiments, analyzed part of the data, designed and
431
supervised the study, researched data and contributed to the writing of the manuscript.
432
KK, KV, PS, AH, AM, AK, TN performed part of the experiments and analysed data.
433
MH contributed to the writing of the manuscript and SKP designed and supervised the
434
study.
435
436
Grants, sponsors, and funding sources: No grant support was received for this study.
437
438
Conflict of Interest: None
439
440
441
442
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443
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Figure Legends
599
600
Figure 1. Correlation plots between free fat mass percentage changes and (A) Daily
601
carbohydrate energy intakes and (B) Daily protein energy intakes, for the total of
602
participants (n=30)
21
603
604
22
605
Figure 2. Correlation plots between C-reactive protein percentage changes and (A) Daily
606
carbohydrate energy intakes and (B) Daily protein energy intakes, for the total of
607
participants (n=30)
608
609
23
610
Figure 3. Summarized model of the effects of three different hypocaloric (-700 kcal/day)
611
diets, Mediterranean Diet, High Protein diet and High Protein-Whey Supplementation
612
diet on body composition and examined biochemical blood markers.
613
614
615
616
617
Table 1. Characteristics of the three nutritional interventions.
Mediterranean (n=10)
Regular
Intervention
Total Daily
Energy
Expenditure
(kcal)
Energy Intake
(kcal)
Energy Balance
(kcal)
Carbohydrates
(g)
Carbohydrates
(kcal)
Carbohydrates
as Percentage of
Total Calories
Intake (%)
Groups (Hypocaloric Diets)
High Protein (n=10)
Regular
Intervention
High Protein-Whey (n=10)
Regular
Intervention
2486.17±450.8
2531.96±385.3
2536.74±421.59
2517.54±410.12 2556.01±486.25 2544.82±426.37
9
4
2582.89±614.2 1851.10±438.60 2642.12±407.2 1851.30±424.12
1882.13±417.81
2662.17±587.98
5
*
2
*
*
96.72±74.12
110.16±65.98*
106.09±71.02* -642.71±173.23
684.41±182.60*
666.23±190.68*
Carbohydrates
258.28±59.14*
341.29±48.34
347.50±55.49 201.88±48.86* M 350.28±66.92 207.55±48.56* M
HP, HPW
1365.16±201.3 1081.12±136.59 1390.77±281.9
1401.14±267.68
807.53±95.46* M
830.20±94.24* M
7
*
8
*
52.85±12.60
Fibers (g)
27.59±7.92
Soluble Fibers
(g)
4.20±2.55
55.81±2.12* HP,
52.60±15.30
43.62±2.32* M
52.63±14.25
44.11±2.30* M
HPW
26.58±10.83
24.90±5.26 M
21.07±7.53
24.28±5.18 M
7.22±2.70*
5.85±2.85
5.27±1.26
4.84±2.16
5.87±1.59
HPW
41.28±4.53* HP,
24
Insoluble Fibers
(g)
Sugar (g)
Monosaccharide
s (g)
Disaccharides
(g)
Fat (g)
Fat (kcal)
Fat as
Percentage of
Total Calories
Intakes (%)
Saturated Fatty
Acids (g)
Monounsaturate
d Fatty Acids (g)
Polyunsaturated
Fatty Acids (g)
Trans Fatty
Acids (g)
Cholesterol (mg)
9.63±7.57
11.29±2.37
8.9±4.06
10.87±3.29
63.71±15.99
61.43±7.89 M
60.44±13.20
61.28±3.52 M
HPW
13.35±8.27
18.37±3.58 M
14.31±6.96
18.41±2.94 M
10.59±7.87
16.48±7.96*
7.97±7.99
14.25±2.22*
8.30±5.87
14.73±3.24
93.72±37.59
843.52±100.11
57.5±9.3*
517.5±84.3*
95.47±37.05
859.23±148.21
55.9±10.1*
503.11±87.1*
32.65±10.25
27.95±1.5
32.05±14.41
27.45±0.9
32.27±16.12
26.73±0.9
25.93±12.76
7.81±1.40*
29.07±12.29
7.25±2.62*
28.93±10.56
7.23±3.22*
32.68±15.44
22.58±3.86*
36.50±14.64
27.61±5.96*
37.49±17.71
24.74±5.19*
7.58±4.15
12.06±2.73*
7.12±3.00
12.99±3.01*
8.00±2.56
11.89±5.24*
4.02±3.48
2.11±1.25*
3.89±1.59
1.99±1.52*
5.02±3.25
2.14±1.33*
60.27±20.07
14.80±12.70
12.48±1.47*
49.93±8.06*
HP,
HPW
21.73±2.69* HP,
Fats
94.11±27.28
56.5±8.5*
846.02±109.13 508.18±77.2*
Proteins (g)
360.47±99.47 151.29±67.05* 348.11±110.24 147.78±55.22* 364.81±71.11 150.98±43.66*
Protein
73.20±14.21 HP,
92.81±30.00
98.21±21.78 133.89±29.78* M 95.06±26.15 134.94±29.80* M
HPW
Proteins (kcal)
371.24±75.23
Proteins as
Percentage of
Total Calories
Intakes (%)
14.37± 4.12
Med Diet Score
Cereals
(servings/week)
Potatoes
(servings/week)
Fruits
(servings/week)
Vegetables
(servings/week)
Legumes
(servings/week)
Fish
(servings/week)
Red Meat
(servings/week)
Poultry
(servings/week)
Full-fat dairy
products
(servings/week)
Olive oil
(teaspoons/ week)
618
619
620
621
9.11±7.33
32.28±7.25
292.81±63.21 HP,
539.79±129.22*
380.24±80.12
28.93±1.45* M
14.28±8.12
28.68±1.90* M
Med Diet Score and Components
44.40±7.25* HP,
30.28±4.88
36.90±4.98 M
HPW
30.19±6.20
38.44±4.76 M
15.87±0.49 HP,
HPW
392.84±66.66
535.58±119.15*
M
HPW
14.86±7.77
M
7.95±5.23
31.30±2.21*
9.10±6.98
32.00±6.28*
7.65±5.43
30.60±7.84*
4.00±2.54
6.50±1.88*
4.65±3.65
5.70±1.68*
3.70±1.93
5.45±1.67*
9.45±5.83
21.30±1.47*
10.95±6.29
20.60±1.80*
10.45±6.21
21.60±1.10*
11.45±8.94
27.75±6.63*
11.40±6.85
24.15±5.64*
15.45±10.25
24.80±6.28*
1.80±0.94
1.70±0.63
1.60±0.73
1.67±0.45
1.70±0.99
1.50±0.55
0.85±0.57
2.50±0.55*
1.15±1.00
1.90±0.84
0.90±0.67
1.94±0.47
3.10±2.31
2.75±1.11* M
4.00±1.00
2.00±1.01* M
HPW
3.60±2.02
9.30±0.94* M
4.00±2.59
9.25±1.68* M
11.65±7.52
3.25±1.11*
13.90±8.25
2.89±1.25*
12.45±7.99
3.01±1.45*
3.25±2.14
7.00±1.00
4.57±2.82
7.01±0.94
5.50±2.41
6.89±1.25
3.80±1.39
2.90±1.83
1.55±0.63*
HP,
HPW
4.20±0.94* HP,
Values are mean ± SD. (*) denotes the significant differences between pre to post values in each group
separately. Letters denote statistical significant difference (p < 0.05) per variable, between the marked
groups (where M = Mediterranean Diet, HPW = High Protein-Whey Diet, HP = High Protein). DRI:
Dietary Reference Intakes
25
622
623
624
625
626
627
Table 2. Mean values and percentage changes of participants’ anthropometrics
characteristics, body composition and resting metabolic rate before and after
interventions
Mediterranean (n=10)
Pre
Body
Mass
(Kg)
Body
Mass
Index
(kg·m-2)
Percenta
ge Body
Fat (%)
628
629
630
631
632
633
HPW
4.1±2.
28.4±2.7 26.6±3.1* HP,
2
HPW
27.1±7.9* 5.9±4.
33.0±7.8
HPW
2# HP,
Total
Body
Water
(%)
55.4±5.3
58.7±9.1 1.3±1.
HP, HPW
1 HP,
HPW
6.6±0.6
54.2±7.2 1.2±0.
8
6.4±0.9 HP, 2.0±1.
HPW
1 HP,
HPW
1.4±0.
1708.9±35 1722.1±32 HP,
9
0.5
5.8
HPW
Partial eta
squared (η2)
Grou
TimGrou
pX
e
p
Time
86.7±7.9 84.6±10.2*1.7±1.
2M
85.7±7.2 84.3±7.2 1.2±1.
0M
0.71
0.0360.262
4
29.1±2.5 27.9±3.2 2.3±1.
9M
28.7±2.2 27.9±2.1 1.7±1.
5M
0.74
0.1280.315
7
1.7±1.
5# M, HP
0.45
0.2250.394
3
7.9±3.
2M
0.22
0.1910.155
8
52.7±8.5 50.9±6.4 1.8±0.
9
54.4±8.7 52.2±7.4 2.2±1.
1
0.01
0.0340.020
2
6.8±0.8 6.5±0.8* M 4.4±2.
2M
6.9±0.7
6.4±0.5* 5.2±2.
M
6M
0.26
0.1800.182
4
1923.4±31 1750.5±2
8.9±2.
6.6
90. 3
8 M, HP
0.05
0.0790.071
0
Post
Chang
e (%
or Δ#)
High Protein-Whey
(n=10)
Chang
e (%
or Δ#)
Pre
32.0±8.7* 2,0±1.
34.3±8.1
HPW
8# M,
HPW
60.4±9.8
Resting
Metabol
ic Rate
(kcal·da
y-1)
Chang
e (%
or Δ#)
3.5±1.
84.1±8.7 79.6±9.3* HP,
1
Free Fat
Mass
(kg)
Phase
Angle
(O )
Post
High Protein (n=10)
Pre
35.5±9.1
Post
33.8±8.9
HP, M
HPW
61.5±8.9
57.2±10.1*
4.9±3.
M
1M
1905.4±24 1816.7±26 4.6±2.
3.1
9.4
7 M,
HPW
59.1±11.2
54.4±7.1*
M
Values are mean ± SD. Δ: the difference between pre to post values; %: the percentage changes of post
compared to pre values. (#) denote Δ. Letters denote statistical significant difference (p < 0.05) per
variable, between the marked groups (where M = Mediterranean Diet, HPW = High Protein-Whey Diet, HP
= High Protein). (*) denote the significant differences between pre and post intervention values, in each
group separately (p<0.05).
26
634
635
Table 3. Mean values and percentage changes of participants’ blood markers before and
after interventions
Mediterranean (n=10)
Pre
Triglycerides
(mg∙dl-1)
Cholesterol
(mg∙dl-1)
High Density
Lipoprotein
(mg∙dl-1)
Low Density
Lipoprotein
(mg∙dl-1)
Post
Chang
e (%)
158.2±3091.0±25.4*H
42.4±15
P, HPW
.9
.4 HP, HPW
185.7±21145.1±30.4*
21.8±5.
HP, HPW
.2
6 HP, HPW
38.4±7.9
41.1±7.1*HP,18.2±12
HPW
.9 HP, HPW
High Protein (n=10)
Pre
Post
Chang
e (%)
187.3±31 171.0±24. -8.7±6.2
M
.7
9M
188.1±15 181.4±25. -3.5±2.8
M
.4
9M
0.19
0.185 0.205
9
38.2±7.1* 3.5±3.1
39.4±10. 39.2±10.9 0.5±5.1
M
M,HP
4
0.22
0.201 0.228
2
138.7±31 129.5±50. -6.6±4.9
M,HP
.9
9M
0.32
0.421 0.309
1
9.81±11.
5* M
0.25
0.389 0.325
9
9.9±1.1* 54.6±32.
HP, M
7 M,HP
0.20
0.159 0.149
9
0.15
0.117 0.241
6
36.9±9.2
M
M,HPW
51.1±6.7 54.9±5.8 7.4±3.5
Monocyte (%)
Urea
(mg∙dl-1)
17.9±10
.9 HP, HPW
5.3±0.9 *HP,
6.2±0.9
14.5±6.
HPW
1 HP, HPW
HP,
28.8±6.9 -2.1±0.4
29.4±6.2
HPW
HP, HPW
34.4±4.2
28.4±7.1*
HP, HPW
11.1±8.
8 HP, HPW
Creatine
132.4±89101.8±53.9*
25.4±11
HP, HPW
-1
.0
Kinase (U∙L )
.2 HP, HPW
C-Reactive
0.2±0.1 HP,
0.3±0.1
33.3±10
HPW
-1
Protein (mg∙dl )
.1 HP, HPW
Creatinine
(mg∙dl-1)
0.9±0.1
0.8±0.1 HP,
HPW
79.5±9.6
86.4±10.4
8.6±8.4
*M
81.5±6.4 89.5±7.4
6.3±1.5
7.8±1.5* 23.8±18
M, HPW
.4 M,HPW
6.4±1.8
0.29
0.302 0.189
0
31.9±13.
3 M,HP
0.19
0.243 0.583
7
42.7±8.2* 40.46±20
M
.1 M,HP
0.58
0.371 0.227
4
72.1±36.
4 M,HP
0.60
0.325 0.495
7
130.9±74 169.9±80. 29.7±13
.1
9* M .2 M,HPW
129.9±75 185.4±70. 42.7±16.
.6
2* M
6 M,HP
0.23
0.245 0.287
3
66.6±40
0.3±0.1 0.5±0.2* M M,HPW
.1
266.6±55
0.3±0.2 1.1±0.3* M
.1 M,HP
0.21
0.282 0.341
8
206.5±51 255.6±40. 23.7±9.9
M,HP
.8
3* M
0.38
0.401 0.300
1
48.7±17.
5 M,HP
0.28
0.181 0.499
9
40.8±10. 62.7±10.7 53.6±28.
6
* HP, M
2 M,HP
0.73
0.399 0.610
8
40.3±4.6* 14.8±8.
M
2M
22.5±10
6.2±1.6 7.6±1.3* M M,HPW
.1
30.4±7.4
38.1±7.1* 25.3±14
M
.6 M,HPW
36.1±20
1.1±0.3 1.5±0.2* M M,HPW
.1
216.1±35189.4±26.3*
12.3±6.
HP, HPW
.6
7 HP, HPW
212.4±33 235.4±29. 10.9±7.
.7
9* M
7 M,HPW
3.8±0.8 HP,
-9.5±5.2
30±10.9
4.0±1.4 5.2±0.9* M M,HPW
23.1±10
.7 HP, HPW
42.0±9.1
Gamma-
16.8±6.9
39.1±8.5
20.3±4.3
HPW
30.1±9.1 HP,
HPW
18.9±5.0 HP, -6.8±2.3
HPW
HP, HPW
16.8±10.
2.3±1.1
17.2±11.7 HP, HPW
5
15.0±9.9
HPW
10.71±4
52.4±9.8 59.9±8.1* 14.3±6.4
M
35.1±5.2
Lactate
Dehydrogenase
(U∙L-1)
Uric Acid
(mg∙dl-1)
Serum
Ammonia
(μg∙dl-1)
Aspartate
Transaminase
(U∙L-1)
Alanine
Transaminase
(U∙L-1)
4.2±0.9
Change
(%)
0.20
0.227 0.288
0
Neutrophils (%) 55.1±6.9 56.1±7.0 1.8±1.2
Lymphocyte
(%)
Post
162.3±41 148.8±31. -8.3±4.4
M,HP
.7
9* M
142.2±27 121.3±34.
14.6±9.
M
.6
4
7 M,HPW
White Blood
Cells (103/μL)
Pre
Partial eta
squared (η2)
Grou
Tim Grou
pX
e
p
Time
159.3±27 126.7±40.
20.4±12
M
.4
4*
.9 M,HPW
141.7±20110.4±39.4*
22.7±15
HP, HPW
.9
.1 HP, HPW
71.9±5.1*HP,
80.1±7.8
14.5±10
HPW
.7
6.1±1.4 HP, -3.2±1.1
6.1±1.4
HPW
HPW, HP
Glucose (mg∙dl1
)
High Protein-Whey
(n=10)
50.4±10.0 20.0±12
* M, HPW .2 M,HPW
36.9±7.3
43.6±9.2* 18.1±9.1
M
6.3±1.3 8.3±1.1* M
30.4±7.1
1.1±0.2 1.9±0.2* M
4.1±1.1 6.1±1.5* M
20.7±10. 28.4±15.4 37.3±21
4
*M
.4 M
21.8±5.8
31.9±8.8* 46.3±22.
M
7M
0.35
0.302 0.329
2
17.1±10.
22.2±14
20.9±7.6 M,HPW
4
.1
15.9±12.
61.0±17.
25.6±12.7
1
4 M,HP
0.21
0.175 0.164
0
25.9±6.3* 51.4±22.
M, HP
5 M,HP
0.18 0.199 0.366
16.1±4.7
18.1±5.6 12.4±6.
HPW
4 M,HPW
27
17.1±6.0
Glutamyltransfe
rase (U∙L-1)
Serum Albumin
(g∙dl-1)
Serum Total
Protein (g∙dl-1)
636
637
.1 HP, HPW
4.3±0.1
4.4±0.1 HP, 2.3±0.7
HPW
HP, HPW
7.0±0.5 6.9±0.6 HPW
-1.2±0.4
HP, HPW
9
4.2±0.1
6.7±0.4
4.9±0.7 M, 16.1±7.
HPW
3 M,HPW
7.0±0.2 4.4±2.1
HPW
M,HPW
4.3±0.1
6.9±0.5
5.9±0.9* 37.2±13.
M, HP
9 M,HP
7.8±0.3* 13.1±5.5
M, HP
M,HP
0.19
0.203 0.231
9
0.45
0.221 0.350
7
Values are mean ± SD. Letters denote statistical significant difference (p < 0.05) per variable, between the
marked groups (where M = Mediterranean Diet, HPW = High Protein-Whey Diet, HP = High Protein).
638
639
640
641
642
643
644
645
Table 4. Correlations between carbohydrates and protein daily energy intakes and
percentage changes of body composition and of selected blood markers after 6 weeks of
the nutritional interventions for all participants as a group (n=30). Only significant
correlations are presented (p<0.05).
Daily Energy (kcal)
Percentage
Changes (%)
Body Mass
Body Fat Mass
Free Fat Mass
Resting Metabolic
Rate
Triglycerides
Low Density
Lipoprotein
White Blood Cells
Urea
Creatinine
Creatine Kinase
C-Reactive
Protein
Lactate
Dehydrogenase
Uric Acid
Aspartate
Transaminase
Alanine
Transaminase
Kcal Difference from Pre
Intervention Nutrition (Δkcal)
Carbohydrates
Proteins
Carbohydrates
Proteins
-0.512
-0.389
0.889
0.518
0.400
-0.799
-0.384
0.400
0.614
0.431
-0.400
0.599
-0.467
0.428
-0.600
0.389
-0.589
-0.666
-0.589
-0.570
0.699
0.703
0.570
0.610
-0.844
0.510
-0.474
0.602
-0.489
0.611
-0.442
0.528
-0.466
0.530
646
647
648
649
28
-0.387
0.397
0.392
-0.403
-0.407
0.415
0.501
-0.514
0.478
0.476
0.372
0.429
0.387
0.401