Bioelectric Impedance Analysis
The Breakdown
Of How It Works
And
Why You Need It
Dr. June Riedlinger, R.Ph., Pharm.D., ND
Certified First Line Therapy Provider
Clinical Relevance of BIA
“BIA is an important clinical tool for
evaluating the metabolic status of patients.
It is inexpensive and noninvasive, and it
provides useful information concerning
altered body composition and membrane
potential at the tissue level measured by
phase angle.”
Jeff Bland PhD.
Clinical Relevance of BIA
“BIA is a simple in-office test that converts
easily obtained electrical measurements
into information about the patient’s body
composition and fluid distribution ...”
Robert Rakowski DC
Biomarkers 2000
• Portable
• Battery powered
• Highly accurate
meter
• Mini-computer
• Inkless printer
(thermal paper)
Pre-test Preparation
• No alcohol within
24 hours
• No exercise for 4
hours
• Avoid caffeine or
food for 4 hours
• Consume 2-4
glasses of water
within 2 hours
Placement of sensor pads
Bioelectric Impedance Analysis
(BIA)
“Bioelectric impedance analysis is a simple,
noninvasive, rapid, portable, reproducible,
and convenient method of measuring body
composition; it is sufficiently accurate for
clinical use and makes fewer physical
demands (than anthropometric techniques).”
JADA 2001;101(10):1209-1212
•Phase Angle, Capacitance,
Resistance and Reactance
Do not rely on input of patient’s
height, weight, age or sex.
• Mass Distribution Results are
based on findings from large
population studies.
• These numbers require
accurate input of a patients
height, weight, sex and age.
Increasing lean body mass will
reduce resistance which is a positive change.
When your lean body mass increases
You will increase reactance which is positive change.
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
STEP 1
Total Body Water/Fat
Free Mass = TBW/FFM


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This marker refers to the
hydration of the patient.
Must be higher than 69%
for a test to be valid.
If <69%, patient should be
put on hydration protocol
and retested in 24-48 hours.
Higher is typically better
Accurate even when subject
is significantly overweight


STEP 1 (CONTINUED)
TBW/Total Weight



Percentage of total weight
that is water
Declines with age
Shows dehydration if person
is significantly overweight.


STEP 2
Phase angle


General indicator of cellular
health
Provides info on cell
membrane potential at the
tissue level
Cellular health tends to be
correlated to a person’s phase angle
Lance
Armstrong
Suboptimal


STEP 3
Intracellular Water


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Healthy cells maintain their
integrity and hold their fluid
inside
>60% is optimal.
Changes with age
Extracellular Water


Water volume outside of the
body cell mass
Higher values may be
related to fluid retention


STEP 4
Fat Free Mass vs. Fat

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Determine the amount of
metabolically active tissue in
the person.
Optimal range depends on sex
and age of person.
BIA can determine both
subcutaneous fat (Love
Handles) as well as visceral fat
found around the organs of
the body.
Advantage over calipers to
assess true health status.
Do You Believe in Miracles?
•Lance Armstrong is
monitored with the BIA
during his preparation
for the Tour
de France.
“. . . we found that fat-free mass was lower
and fat mass was higher in acutely ill and
chronically ill patients than controls.”
J Amer Diet Assoc 2002;102(7):944-955


STEP 5
ECM/BCM

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Ratio of extracellular mass
(non-metabolically active) to
body cell mass (metabolically
active)
Low value is desirable
Upward shift suggests
imbalanced weight loss.
Downward shift suggests
balanced weight loss.
Use Body Composition
Protocol to shift.
“Sarcopenia is the backdrop against which
the drama of disease is played out: a body
already depleted of protein because of
aging is less able to with stand the protein
catabolism that comes with acute illness or
inadequate protein intake.”
JAMA 286(10) (2001)
BIA may be clinically useful for demonstrating
sarcopenic obesity in women at normal body
mass indices, with additional studies
necessary to determine the metabolic reasons
underlying this change in body composition.
Am J Clin Nutrition 1996; 64:472S-477S


STEP 6
Body Mass Index

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BMI correlates with a person’s
health.
Studies show even moderate
BMI shifts mean health
consequences.
Lower is better
Alter using Body Composition
Program.
Weight Gain and
Diabetes Risk
Weight Change Since Age 21
<5 kg
5-10 kg
11+ kg
25
Relative Risk
21.1
20
15
9.1
10
6.3
5
1.0
5.3
3.6
2.5
1.0
2.1
0
<22
22-23
Body Mass Index at Age 21
Adapted from Chan JM, et al. Diabetes Care 1994;17:960-969.
24+
26 -Year Incidence of
Coronary Heart Disease in Men
Incidence/1,000
<50 years
50+ years
600
500
440
400
300
200
366
333
350
255
177
100
0
<25
25-<30
BMI Levels
Adapted from Hubert HB, et al. Circulation 1983;67:968-977.
Metropolitan Relative Weight of 110 is a BMI of approximately 25.
30+
Relationship of BMI to
Excess Mortality
300
250
Age at Issue
20-29
30-39
200
150
100
Low
Risk
50
0
15
20
25
30
High
Moderate
Risk
35
Risk
40
Body Mass Index (kg/[m2])
Bray GA. Overweight is risking fate. Definition, classification,
prevalence and risks. Ann NY Acad Sci 1987;499:14-28.
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STEP 7
Basal Metabolic Rate

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BMR- is the amount of calories
a person burns during a 24
hour period while at rest.
More lean body mass will
increase the BMR
Higher is typically better.
Each person is very unique
Essential in establishing a
proper body composition
program.
Dr. June Riedlinger
R.Ph., Pharm.D., ND
FLT Certified Provider
• FLT is based on
National Institutes of
Health TLC program
recommendations.
• Allows for me to tailor
to your needs.
• Delivers a concise
and effective report of
findings.