Differences in resting metabolic rate between white and African-American young adults.
OBJECTIVE
A reported lower resting metabolic rate (RMR) in African-American women than in white women could explain the higher prevalence of obesity in the former group. Little information is available on RMR in African-American men.


METHODS
We assessed RMR by indirect calorimetry and body composition by DXA in 395 adults ages 28 to 40 years (100 African-American men, 95 white men, 94 African-American women, and 106 white women), recruited from participants in the Coronary Artery Risk Development in Young Adults (CARDIA), Birmingham, Alabama, and Oakland, California, field centers.


RESULTS
Using linear models, fat-free mass, fat mass, visceral fat, and age were significantly related to RMR, but the usual level of physical activity was not. After adjustment for these variables, mean RMR was significantly higher in whites (1665.07 +/- 10.78 kcal/d) than in African Americans (1585.05 +/- 11.02 kcal/d) by 80 +/- 16 kcal/d (p < 0.0001). The ethnic x gender interaction was not significant (p = 0.9512), indicating that the difference in RMR between African-American and white subjects was similar for men and women.


CONCLUSIONS
RMR is approximately 5% higher in white than in African-American participants in CARDIA. The difference was the same for men and women and for lean and obese individuals. The prevalence of obesity is not higher in African-American men than in white men. Because of these reasons, we believe that RMR differences are unlikely to be a primary explanation for why African-American women are more prone to obesity than white women.
Center for Human Nutrition, University of Colorado Health Sciences Center, Denver, Colorado 80262, USA. Teresa.Sharp@UCHSC.edu
Teresa A
TA
Sharp
Melanie L
ML
Bell
Gary K
GK
Grunwald
Kathryn H
KH
Schmitz
Stephen
S
Sidney
Cora E
CE
Lewis
Kim
K
Tolan
James O
JO
Hill
D000273:Adipose Tissue; D000328:Adult; D000375:Aging; D001481:Basal Metabolism; D044383:Black People; D001823:Body Composition; D001827:Body Height; D001835:Body Weight; D002153:Calorimetry, Indirect; D015444:Exercise; D005260:Female; D006801:Humans; D008297:Male; D009765:Obesity / Q000453:epidemiology; D012044:Regression Analysis; D012727:Sex Characteristics; D044465:White People; D001741:Black or African American