Energy Expenditure Differs between Black and White Americans: Implications for Obesity Prevention Research

Abstract

Objective: To assess differences in energy expenditure by race and ethnicity using nationally representative data. Results: We confirmed that Blacks exhibit lower resting energy expenditure than Whites—a difference of approximately 150 to 300 fewer kilocalories per day. This finding was significant in each permutation of our analysis—from the simple association of race and resting energy expenditure to our final regression model adjusted for common confounders (i.e. age, gender, income, and education), body fat content, diabetes, thyroid dysfunction, and weight loss in previous year. Further, we found that energy intake did not differ significantly between Blacks and Whites whereas Blacks were found to expend significantly more energy voluntarily than Whites. Blacks and Whites did not differ significantly in bodyweight, though Blacks were found to be leaner than Whites as evidenced by significantly lower body fat content in the former. Discussion: Our findings suggest that if rates of obesity are to be reduced in Black Americans, recommendations would need to encourage lower levels of average energy intake and higher levels of activity energy expenditure than extant in the general populace. In short, Blacks would need to adopt more austere lifestyle regimens relative to the general populace in order to reduce their rate of obesity below present levels.