Comparability of Resting Energy Expenditure in Nigerians and U.S. Blacks

BACKGROUND:Obesity results from a chronic imbalance between energy intake and energy expenditure. However, experimental evidence of the relative contribution of interindividual differences in energy intake and expenditure (resting or due to physical activity) to weight gain is limited. OBJECTIVE: To assess prospectively the association between baseline measurements of daily energy metabolism and weight changes by studying free-living adult Pima Indians, one of the most obese populations in the world. DESIGN: A study of the pathogenesis of obesity in the Pima Indians living in Southwestern Arizona. The participants were 92 nondiabetic Pima Indians (64M/28F, 35712 y, 3579% body fat; mean7s.d.). At baseline, free-living daily energy metabolism was assessed by doubly labeled water and resting metabolic rate (RMR) by indirect calorimetry. Data on changes in body weight (5.876.5 kg) over a follow-up period of 473 y were available in 74 (49M/25F) of the 92 subjects. RESULTS: The baseline calculated total energy intake (r ¼ 0.25, P ¼ 0.028) and RMR (r ¼ À0.28, P ¼ 0.016) were significantly associated with changes in body weight. The baseline energy expenditure due to physical activity was not associated with changes in body weight. CONCLUSION: Using state-of-the-art methods to assess energy intake and expenditure in free-living conditions, we show for the first time that the baseline calculated total energy intake is a determinant of changes in body weight in Pima Indians. These data also confirm that a low RMR is a risk factor for weight gain in this population.

show abstract

“…31,32 Here, we confirm our previous finding that RMR and long-term body weight changes are negatively related.…”

Section: Discussionsupporting

confidence: 90%

Body weight gain in free-living Pima Indians: effect of energy intake vs expenditure

et al. 2003

View full text Add to dashboard Cite

show abstract

“…While in the current study we were unable to adjust for smaller higher metabolic organ tissue, our results are similar because after adjusting for differences in FFM, differences in REE were no longer significant. It is notable that the black women in the current study had overall smaller FFM (kg) than the white women, this is contrary to the data from the United States that consistently report AA women have either no difference in FFM or, in some cases, greater amounts of FFM than their white counterparts (Carpenter et al, 1998;Weyer et al, 1999;Lovejoy et al, 2001;Kimm et al, 2002;Sharp et al, 2002) but in line with the published data on SA women (Rush et al, 2007) and similar to data on African women living outside the the United States (that is, Nigeria) who have lower body weights, FFM and fat masses than AA women (Luke et al, 2000(Luke et al, , 2002. Body composition differences have been attributed to differences in specific habitual dietary intake patterns and trends in populations undergoing the nutrition transition, as suggested by Popkin (1998).…”

Section: Discussionsupporting

confidence: 53%

“…Differences were attributed to lower REE and physical activity energy expenditure (PAEE). In contrast, other studies report that ethnic differences in EE may be largely attributed to differences in body composition (Shetty et al, 1996;Soares et al, 1998;Luke et al, 2000Luke et al, , 2002. For example, Soares et al (1998) compared REE in men and women of Indian and European ancestry.…”

Section: Introductionmentioning

confidence: 94%

Total daily energy expenditure in black and white, lean and obese South African women

et al. 2008

View full text Add to dashboard Cite

Background/Objectives: In South Africa (SA), the prevalence of obesity in women is 56%, with black women being most at risk (62%). Studies in the United States have demonstrated ethnic differences in resting (REE) and total daily energy expenditure (TDEE) between African American (AA) and their white counterparts. We investigated whether differences in EE exist in black and white SA women, explaining, in part, the ethnic obesity prevalence differences. Subjects/Methods: We measured REE, TDEE and physical activity EE (PAEE) in lean (BMI o25 kg m À2 ) and obese (BMI 430 kg m À2 ) SA women (N ¼ 44, 30±6 year). REE, TDEE, PAEE and total awake EE were measured during a 21 h stay in a respiration chamber. Results: Black and white subjects within obese and lean groups were not significantly different for age, mass, BMI and % body fat. However, fat-free mass (kg FFM) was consistently lower in the black women (Po0.01) in both weight groups. After adjusting EE measurements for differences in FFM, REE was not significantly different for either body weight or ethnicity, although 24 h TDEE (kJ) was significantly greater in the obese women (Po0.01) and white women (Po0.05). Total awake non-PAEE was not significantly different for either groups, while total awake time was only significantly lower for the lean groups (Po0.01). Total PAEE (kJ min À1 ) was significantly lower in the lean (Po0.001) and black groups (Po0.01). Conclusions: In this sample of matched, lean and obese, black and white SA women, differences in TDEE were largely explained by ethnic differences in PAEE, and were not as a result of ethnic differences in REE.

show abstract

“…Alcohol burn tests indicated that the instrument was accurate to within 2% at all times; replicate measurements (nϭ35, up to 1.5 years apart) indicate the intra-individual coefficient of variation of REE to be Ϸ3.5%. 14 Total energy expenditure was measured using the doubly labeled water method in the smaller sample from the 3 sites. 15 Standardized doses of O 18 and deuterium were given at baseline and samples of body fluids were obtained at baseline, at equilibration with total body water and after 10 to 14 days, as previously described.…”

Section: Measurement Of Resting Energy Expenditurementioning

confidence: 99%

Association Between Blood Pressure and Resting Energy Expenditure Independent of Body Size

et al. 2004

Self Cite

View full text Add to dashboard Cite

Abstract-Obesity is an important risk factor for hypertension; however, the pathway through which it raises blood pressure (BP) is poorly understood. Body size is also the primary determinant of energy expenditure, and we therefore examined the joint relationship of energy expenditure and body size to blood pressure. Resting energy expenditure (REE) was measured using respiratory gas exchange in population-based samples of 997 Nigerians and 452 African Americans. In a third sample of 118 individuals, nonresting energy expenditure (ie, physical activity) was measured in addition to REE. The univariate correlation between REE and BP ranged from 0.10 to 0.22 in the 3 samples (PϽ0.001).In multivariate models, adiposity, whether defined by body mass, fat mass, or leptin, was no longer associated with BP, while REE remained highly significant (PϽ0.001). The REE-BP association also persisted after adjustment for physical activity measured with doubly labeled water. The odds ratio for hypertension among persons in the highest quartile versus the lowest quartile of REE, after adjustment for body size, was 1.7. This relationship was not the result of hypertension among the obese, because it did not vary across the range of BMI and was the same in lean Nigerians as in obese Americans. These data suggest that metabolic processes represented by REE may mediate the effect of body size on BP. The interrelationship of REE with sympathetic tone, transmembrane ion exchange, or other metabolic processes that determine energy costs at rest could provide physiological explanations for this observation. . Although height appears to have little or no influence on BP among humans, adiposity has been universally identified as a predictor of increased risk of hypertension. 1,2 Despite substantial efforts, the underlying physiological mechanisms linking excess body fat stores to BP are poorly understood. Obesity is a complex syndrome, representing the joint effect of metabolic alterations as well as lifestyle patterns that involve, among others, a high-calorie/highsodium intake and reduced physical activity. 3 Various regulatory hormones, including insulin and leptin, are increased among the obese, and abnormalities in the renin-angiotensin system have been described. 4 -6 At the same time, a wide range of other metabolic abnormalities, including rates of ion transport and resting sympathetic tone, have been reported in obese hypertensives compared with the non-obese, although these associations are inconsistent. 7 An important challenge faced by studies that attempt to isolate the role of individual components of body composition and energy metabolism is the need to account for their intercorrelation. Although it is often assumed that the size of body fat stores is a primary determinant of hypertension risk, lean body mass increases in parallel with total body weight and is highly correlated with fat mass. 8 In addition, in societies where virtually the entire population experiences some degree of overweight, it may be difficult to iden...

show abstract

Comparability of Resting Energy Expenditure in Nigerians and U.S. Blacks

Cited by 38 publications

References 46 publications

Body weight gain in free-living Pima Indians: effect of energy intake vs expenditure

Body weight gain in free-living Pima Indians: effect of energy intake vs expenditure

Total daily energy expenditure in black and white, lean and obese South African women

Association Between Blood Pressure and Resting Energy Expenditure Independent of Body Size

Contact Info

Product

Resources

About