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Who should not use this device
Bioelectrical Impedance Analysis impedance measurements should not be used by subjects with
the following characteristics:
(1) Electronic medical implants, e.g. cardiac pacemaker
A low level imperceptible electrical current will be sent through the body during measurement,
which may damage the implanted device or result in malfunction.
(2) Prosthetics and amputation
BIA measures impedance measured using an electric current sent through the body through
eight electrode contact points (two for each hand and two for each foot). As the current cannot
flow through prosthetic limbs, measurement is not possible.
(3) Pregnant Women
BIA equations are created based on statistical analysis of sample populations. If subject's
body composition differs significantly from these sample populations, equations derived from
"normal" healthy adults will be inherently less accurate in these subjects. Women undergo a
wide range of body composition changes during pregnancy, including but not limited to
change in fat percentage and body water. Without dedicated algorithms, pregnant women
should use results with caution and professional advice.
Measurement Rules
For best results, Body Composition Analysis should be conducted under specific controlled
conditions. Inconsistent measuring conditions will affect the accuracy and validity of BIA results,
and interpretation of body composition. The information below regarding the effect of various
factors on measurement results is largely sourced from related research by Kushner et al
1
.
Before measurement, please take note of the following:
(1) Do not exercise or perform strenuous physical tasks before measurement.
Strenuous physical tasks and exercise can result in a temporary change in body composition
measurements. As BIA analyzes electrical impedance in the body, activities that might affect
impedance (e.g. increased perspiration, dehydration, blood circulation) may affect
measurement accuracy.
(2) Affect of food and drink on measurement results.
Ingestion of food and drink can affect impedance and weight, and thus analysis results. This
change generally lasts 2-5 hours after each meal. For most accurate results, BIA
measurements should be conducted in a fasting state (e.g. before breakfast)
2
.
Diuretics (e.g. caffeine, alcohol) can cause dehydration, creating an overestimation of body
fat. For most accurate results, diuretics should be avoided prior to measurement.
VI. INSTRUCTIONS FOR OPERATION
1. Kushner RF, Clinical characteristics influencing bioelectrical impedance analysis measurements, 1996
2. R Gallagher, M & Walker, Karen & O'Dea, K. The influence of a breakfast meal on the assessment of body composition
using bioelectrical impedance. European journal of clinical nutrition. 52. 94-7. 10.1038/sj.ejcn.1600520., 1998.
Warning
