Percentage of body fat cutoffs by sex, age, and race-ethnicity in the US adult population from NHANES 1999-2004.
BACKGROUND
To date, there is no consensus regarding adult cutoffs of percentage of body fat or estimated cutoffs on the basis of nationally representative samples with rigorous body-composition measurements.


OBJECTIVE
We developed cutoffs of percentage of body fat on the basis of the relation between dual-energy x-ray absorptiometry-measured fat mass and BMI (in kg/m(2)) stratified by sex, age, and race-ethnicity by using 1999-2004 NHANES data.


METHODS
A simple regression (percentage of body fat = β(0) + β(1) × 1 ÷ BMI) was fit for each combination of sex (men and women), 3 age groups (18-29, 30-49, and 50-84 y of age), and 3 race-ethnicity groups (non-Hispanic whites, non-Hispanic blacks, and Mexican Americans). Model fitting included a consideration of complex survey design and multiple imputations. Cutoffs of percentage of body fat were computed that corresponded to BMI cutoffs of 18.5, 25, 30, 35, and 40 on the basis of estimated prediction equations.


RESULTS
R(2) ranged from 0.54 to 0.72 for men (n = 6544) and 0.58 to 0.79 for women (n = 6362). In men, the percentage of body fat that corresponded to a BMI of 18.5, 25, 30, 35, and 40 across age and racial-ethnic groups ranged from 12.2% to 19.0%, 22.6% to 28.0%, 27.5% to 32.3%, 31.0% to 35.3%, and 33.6% to 37.6%, respectively; the corresponding ranges in women were from 24.6% to 32.3%, 35.0% to 40.2%, 39.9% to 44.1%, 43.4% to 47.1%, and 46.1% to 49.4%, respectively. The oldest age group had the highest cutoffs of percentage of body fat. Non-Hispanic blacks had the lowest cutoffs of percentage of body fat. Cutoffs of percentage of body fat were higher in women than in men.


CONCLUSIONS
Cutoffs of percentage of body fat that correspond to the current US BMI cutoffs are a function of sex, age, and race-ethnicity. These factors should be taken into account when considering the appropriateness of levels of percentage of body fat.
Department of Epidemiology and Population Health, Albert Einstein College of Medicine, Bronx, NY 10461, USA. moonseong.heo@einstein.yu.edu
Moonseong
M
Heo
Myles S
MS
Faith
Angelo
A
Pietrobelli
Steven B
SB
Heymsfield
D015502:Absorptiometry, Photon / Q000379:methods; D000273:Adipose Tissue; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D044383:Black People; D001823:Body Composition; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D017058:Mexican Americans; D008875:Middle Aged; D009749:Nutrition Surveys; D012016:Reference Values; D012737:Sex Factors; D014481:United States; D044465:White People; D055815:Young Adult; D001741:Black or African American