This document provides average body composition statistics from the NHANES-III data set for American males and females by age group. It includes averages for height, weight, total body water, fat free mass, fat mass, body mass index, basal metabolic rate, and phase angle. The purpose is to provide a reference for comparing individuals' body composition to the population in the NHANES-III study, but the values do not indicate ideal or target ranges. Usage examples are provided to understand how to read the tables and find specific average ranges.

1. American Population Body Composition Averages from the NHANES-III Data Set
Introduction
The purpose of this document is to provide the statistical averages of the body composition of average
Americans and provide reference averages with which an individual may be compared to the population
examined in NHANES-III.
Scope
The following eighteen (18) tables illustrate the average body composition of Americans. The tables
DO NOT illustrate "ideal" or "target" values. Furthermore, the tables may show values that are consid-
ered to be "unhealthy" by medical professionals. The purpose of this document is strictly limited to pro-
viding a body composition reference of the population examined in NHANES-III.
Methods
The values of Total Body Water, Fat Free Mass, Fat Mass, Body Mass Index, Basal Metabolic Rate, and
Phase angle for males and females were calculated by using the reference data as reported in NHANES-
III and applying those values to the RJL Systems equations referred to as "NHANES-III" [1,2,3].
Instructions
The reference tables are split by gender into two sections of nine (9) tables each. Each table shows refer-
ence values for decade age groups. The first table in each section reports average height and weight from
the NHANES-III data set and include the following parameters.
Table 1. NHANES Baseline
Age decade of age
n observations in each decade
Average weight Kg average weight for decade expressed in kilograms
Average weight Lb average weight for decade expressed in pounds
Average height Cm average height for decade expressed in centimeters
Average height In average height for decade expressed in inches
Following each baseline are tables for averages of:
Table 2. TBW (Total Body Water)
Table 3. ICW (Intracellular Water)
Table 4. ECW (Extracellular Water)
Table 5. FFM (Fat Free Mass)
Table 6. FM (Fat Mass)
Table 7. BMI (Body Mass Index)
Table 8. BMR (Basal Metabolic Rate)
Table 9. Phase Angle (Phase Angle)

2. -2-
Each table includes the following statistics in both English and Metric units:
Mean the center of the average range
Standard Deviation (Std Dev) the variance of the average range
And may also include:
Percent of weight the percentage of total weight
USAGE EXAMPLE
If you want to determine the average range for body fat, in pounds, for males in the 20-29 year age
decade.
1. Find the table named Fat Mass in the Male section.
2. Find the column labeled 20-29.
3. Find the rows labeled Mean (lb) and Std Dev (lb)
4. The mean is 42.5 lbs and the standard deviation is 20.3 lbs. Add 20.3 to 42.5 to find the high end
of the average range and subtract 20.3 to find the low end of the average range.
5. The average fat mass of an American male between the ages of 20 and 29 is between 22.2 and
62.8 pounds.
[1] Shumei S Sun, W Cameron Chumlea, Steven B Heymsfield, Henry C Lukaski, Dale Schoeller, Karl
Friedl, Robert J Kuczmarski, Katherine M Flegal, Clifford L Johnson, and Van S Hubbard Development
of bioelectrical impedance analysis prediction equations for body composition with the use of a multi-
component model for use in epidemiologic surveysAm J Clin Nutr 2003;77:331-40.
[2] WC Chumlea, SS Guo, RJ Kuczmarski, KM Flegal, CL Johnson, SB Heymsfield, HC Lukaski, K
Friedl and VS Hubbard Body composition estimates from NHANES III bioelectrical impedance
data/fRInternational Journal of Obesity (2002) 26, 1596-1609
[3] Giuseppe Sergi, et. al. Accuracy of Bioelectrical Impedance Analysis in Estimation of Extracellular
Space in Healthy Subjects and in Fluid Retention States. Annals of Nutrition and Metabolism (1994)
38, 158-165

3. -3-
NHANES Averages for males
NHANES base line for males
Age 10-19 20-29 30-39 40-49 50-59 60-69 70-79 80-89 90-99
n= 1379 1553 1383 1155 792 1055 724 472 32
average wt Kg = 64.3 77.4 81.6 83.7 84.1 81.7 77.5 72.6 65.1
average wt Lb = 141.8 170.6 179.9 184.4 185.5 180.2 170.9 160.1 143.5
average ht Cm= 168.7 173.8 174.8 174.3 174.5 172.5 171.2 169.5 167.1
average ht In= 66.4 68.4 68.8 68.6 68.7 67.9 67.4 66.7 65.8
Total body water (Male)
Age 10-19 20-29 30-39 40-49 50-59 60-69 70-79 80-89 90-99
Mean (liter) 37.8 43.2 45.0 45.6 45.7 44.2 42.4 40.3 37.1
Mean (lb) 83.2 95.3 99.2 100.5 100.7 97.4 93.6 88.7 81.8
Std dev (liter) ± 8.0 ± 7.2 ± 7.5 ± 7.4 ± 7.2 ± 6.9 ± 6.7 ± 6.0 ± 6.0
Std dev (lb) ±17.6 ±16.0 ±16.5 ±16.3 ±15.9 ±15.3 ±14.8 ±13.2 ±13.2
percent of wt 58.7 55.8 55.1 54.5 54.3 54.0 54.8 55.4 57.0
Intracellular water (Male)
Age 10-19 20-29 30-39 40-49 50-59 60-69 70-79 80-89 90-99
Mean (liter) 22.7 25.6 26.5 26.7 26.5 25.6 24.5 23.1 21.4
Mean (lb) 50.0 56.5 58.3 58.8 58.5 56.5 54.0 50.9 47.1
Std (liter) ± 4.1 ± 3.7 ± 3.8 ± 3.7 ± 3.6 ± 3.4 ± 3.2 ± 2.9 ± 3.0
Std (lb) ± 9.0 ± 8.1 ± 8.4 ± 8.2 ± 7.9 ± 7.6 ± 7.2 ± 6.4 ± 6.6
percent of TBW = 60.0 59.3 58.8 58.5 58.1 58.0 57.7 57.3 57.6
Extracellular water (Male)
Age 10-19 20-29 30-39 40-49 50-59 60-69 70-79 80-89 90-99
Mean (liter) 15.1 17.6 18.5 18.9 19.1 18.5 18.0 17.2 15.7
Mean (lb) 33.3 38.8 40.9 41.7 42.2 40.9 39.6 37.9 34.7
Std (liter) ± 3.9 ± 3.6 ± 3.7 ± 3.7 ± 3.7 ± 3.5 ± 3.5 ± 3.2 ± 3.1
Std (lb) ± 8.7 ± 7.9 ± 8.2 ± 8.1 ± 8.1 ± 7.8 ± 7.7 ± 7.0 ± 6.8
percent of TBW = 40.0 40.7 41.2 41.5 41.9 42.0 42.3 42.7 42.4
Fat free mass (Male)
Age 10-19 20-29 30-39 40-49 50-59 60-69 70-79 80-89 90-99
Mean (kg) 50.6 58.1 60.6 61.4 61.5 59.4 57.0 54.0 49.7
Mean (lb) 111.7 128.2 133.6 135.3 135.6 131.0 125.7 119.1 109.6
Std dev (kg) ±10.8 ± 9.9 ±10.2 ±10.1 ± 9.8 ± 9.3 ± 9.0 ± 7.9 ± 7.9
Std dev (lb) ±23.8 ±21.8 ±22.6 ±22.2 ±21.6 ±20.6 ±19.8 ±17.4 ±17.5
percent of wt 78.7 75.1 74.2 73.3 73.1 72.7 73.6 74.4 76.4
Fat mass (Male)
Age 10-19 20-29 30-39 40-49 50-59 60-69 70-79 80-89 90-99
Mean (kg) 13.7 19.3 21.0 22.3 22.6 22.3 20.5 18.6 15.4
Mean (lb) 30.2 42.5 46.4 49.2 49.9 49.2 45.2 41.0 33.9
Std dev (kg) ± 8.3 ± 9.2 ± 8.8 ± 8.5 ± 8.3 ± 7.7 ± 7.1 ± 6.6 ± 6.6
Std dev (lb) ±18.3 ±20.3 ±19.3 ±18.7 ±18.4 ±16.9 ±15.6 ±14.6 ±14.6
percent of wt 21.3 24.9 25.8 26.7 26.9 27.3 26.4 25.6 23.6

4. -4-
Body mass index (BMI) (Male)
Age 10-19 20-29 30-39 40-49 50-59 60-69 70-79 80-89 90-99
Mean BMI 22.4 25.5 26.6 27.5 27.6 27.4 26.4 25.2 23.3
Std dev BMI ± 4.7 ± 4.9 ± 5.0 ± 4.9 ± 4.8 ± 4.4 ± 4.2 ± 3.8 ± 3.6
Basal metabolic rate BMR (Male)
Age 10-19 20-29 30-39 40-49 50-59 60-69 70-79 80-89 90-99
Mean BMR 1693.1 1836.9 1833.9 1794.2 1729.7 1619.5 1491.9 1352.6 1188.4
Std dev BMR ±265.2 ±256.3 ±253.7 ±250.8 ±243.7 ±227.6 ±216.3 ±190.6 ±190.3
Phase angle (Male)
Age 10-19 20-29 30-39 40-49 50-59 60-69 70-79 80-89 90-99
Mean PA 8.0 8.7 8.5 8.2 7.6 7.1 6.4 5.7 5.4
Std dev PA ± 1.0 ± 0.9 ± 0.9 ± 1.0 ± 0.9 ± 0.9 ± 1.0 ± 0.9 ± 1.2

5. -5-
NHANES Averages for females
NHANES base line for females
Age 10-19 20-29 30-39 40-49 50-59 60-69 70-79 80-89 90-99
n= 1448 1511 1632 1248 907 1031 817 477 44
average wt Kg = 59.5 66.1 73.0 74.7 75.4 71.7 68.2 61.8 53.7
average wt Lb = 131.2 145.8 160.9 164.6 166.2 158.0 150.4 136.2 118.4
average ht Cm= 160.6 161.6 161.7 161.5 160.8 159.0 157.5 155.1 153.5
average ht In= 63.2 63.6 63.7 63.6 63.3 62.6 62.0 61.0 60.4
Total body water (Female)
Age 10-19 20-29 30-39 40-49 50-59 60-69 70-79 80-89 90-99
Mean (liter) 29.5 31.2 33.1 33.3 33.3 32.0 31.3 29.3 27.5
Mean (lb) 65.0 68.8 73.0 73.5 73.5 70.6 69.1 64.7 60.7
Std dev (liter) ± 4.5 ± 4.8 ± 5.5 ± 5.4 ± 5.3 ± 4.9 ± 4.9 ± 4.1 ± 3.4
Std dev (lb) ± 9.9 ±10.5 ±12.1 ±11.9 ±11.8 ±10.8 ±10.7 ± 9.0 ± 7.6
percent of wt 49.6 47.2 45.4 44.7 44.2 44.7 45.9 47.5 51.2
Intracellular water (Female)
Age 10-19 20-29 30-39 40-49 50-59 60-69 70-79 80-89 90-99
Mean (liter) 16.1 16.9 17.6 17.6 17.5 16.8 16.4 15.4 14.5
Mean (lb) 35.5 37.2 38.8 38.9 38.6 37.1 36.2 34.0 32.0
Std (liter) ± 1.9 ± 2.0 ± 2.3 ± 2.2 ± 2.2 ± 2.0 ± 2.0 ± 1.7 ± 1.4
Std (lb) ± 4.2 ± 4.4 ± 5.0 ± 4.9 ± 4.8 ± 4.5 ± 4.4 ± 3.7 ± 3.2
percent of TBW = 54.6 54.0 53.1 52.9 52.5 52.6 52.4 52.6 52.8
Extracellular water (Female)
Age 10-19 20-29 30-39 40-49 50-59 60-69 70-79 80-89 90-99
Mean (liter) 13.4 14.4 15.5 15.7 15.8 15.2 14.9 13.9 13.0
Mean (lb) 29.5 31.7 34.2 34.6 34.9 33.4 32.9 30.7 28.6
Std (liter) ± 2.6 ± 2.8 ± 3.3 ± 3.2 ± 3.2 ± 2.9 ± 2.9 ± 2.5 ± 2.1
Std (lb) ± 5.8 ± 6.1 ± 7.2 ± 7.0 ± 7.0 ± 6.4 ± 6.4 ± 5.5 ± 4.6
percent of TBW = 45.4 46.0 46.9 47.1 47.5 47.4 47.6 47.4 47.2
Fat free mass (Female)
Age 10-19 20-29 30-39 40-49 50-59 60-69 70-79 80-89 90-99
Mean (kg) 39.8 42.1 44.5 44.8 44.8 42.9 41.9 39.1 36.7
Mean (lb) 87.8 92.8 98.2 98.9 98.7 94.7 92.3 86.3 80.8
Std dev (kg) ± 5.9 ± 6.2 ± 7.4 ± 7.1 ± 7.0 ± 6.4 ± 6.3 ± 5.2 ± 4.1
Std dev (lb) ±13.0 ±13.7 ±16.2 ±15.6 ±15.5 ±14.1 ±13.9 ±11.6 ± 9.0
percent of wt 66.9 63.7 61.0 60.1 59.4 59.9 61.4 63.3 68.3
Fat mass (Female)
Age 10-19 20-29 30-39 40-49 50-59 60-69 70-79 80-89 90-99
Mean (kg) 19.7 24.0 28.5 29.8 30.6 28.7 26.3 22.7 17.0
Mean (lb) 43.4 52.9 62.8 65.7 67.5 63.3 58.0 49.9 37.5
Std dev (kg) ±10.0 ±10.7 ±13.1 ±11.8 ±11.9 ±10.3 ± 9.6 ± 7.7 ± 6.1
Std dev (lb) ±22.0 ±23.7 ±28.9 ±25.9 ±26.1 ±22.7 ±21.1 ±17.1 ±13.5
percent of wt 33.1 36.3 39.0 39.9 40.6 40.1 38.6 36.7 31.7

6. -6-
Body mass index BMI (Female)
Age 10-19 20-29 30-39 40-49 50-59 60-69 70-79 80-89 90-99
Mean BMI 23.0 25.3 27.9 28.6 29.1 28.4 27.5 25.7 22.8
Std dev BMI ± 5.2 ± 5.8 ± 7.2 ± 6.6 ± 6.6 ± 5.9 ± 5.5 ± 4.5 ± 3.5
Basal metabolic rate BMR (Female)
Age 10-19 20-29 30-39 40-49 50-59 60-69 70-79 80-89 90-99
Mean BMR 1443.7 1465.3 1484.7 1457.0 1412.9 1327.0 1245.8 1137.1 1023.9
Std dev BMR ±147.4 ±156.6 ±189.7 ±174.5 ±176.1 ±155.0 ±147.4 ±118.8 ±82.9
Phase angle (Female)
Age 10-19 20-29 30-39 40-49 50-59 60-69 70-79 80-89 90-99
Mean PA 7.5 7.8 7.7 7.6 7.1 6.7 6.2 5.6 5.0
Std dev PA ± 0.8 ± 0.8 ± 0.9 ± 0.8 ± 0.9 ± 0.9 ± 1.0 ± 0.9 ± 0.7