Energy expenditure in adults living in developing compared with industrialized countries: a meta-analysis of doubly labeled water studies.

BACKGROUND: There is an assumption that people in developing countries have a higher total energy expenditure (TEE) and physical activity level (PAL) than do people in developed nations, but few objective data for this assertion exist. OBJECTIVE: We conducted a meta-analysis of TEE and PAL by using data from countries that have a low or middle human development index (HDI) compared with those with a high HDI to better understand how energy-expenditure variables are associated with development status and population differences in body size. DESIGN: We performed a literature search for studies in which energy expenditure was measured by using doubly labeled water. Mean data on age, weight, body mass index (BMI; in kg/m(2)), TEE, and PAL were extracted, and HDI status was assessed. Pooled estimates of the mean effect by sex were obtained, and the extent to which age, weight, HDI status, and year of publication explained heterogeneity was assessed. RESULTS: A total of 98 studies (14 studies from low- or middle-HDI countries) that represented 183 cohorts and 4972 individuals were included. Mean (±SE) BMI was lower in countries with a low or middle HDI than in those with a high HDI for both men and women (22.7 ± 1.0 compared with 26.0 ± 0.7, respectively, in men and 24.3 ± 0.7 compared with 26.6 ± 0.4, respectively, in women). In meta-regression models, there was an inverse association of age (P < 0.001) and a positive association of weight (P < 0.001) with TEE for both sexes; there was an association of age only in men with PAL (P < 0.001). There was no association of HDI status with either TEE or PAL. CONCLUSION: TEE adjusted for weight and age or PAL did not differ significantly between developing and industrialized countries, which calls into question the role of energy expenditure in the cause of obesity at the population level.

Relative height and weight among children and adolescents of rural southwestern Nigeria.

BACKGROUND: There are few data describing the relative height and weight patterns of children and adolescents in rural Nigeria, despite a prevalence of stunting of over 38% among children younger than 5 years. AIM: The present study documented the height and weight patterns relative to international standards among children and adolescents aged 5-20 years in rural Nigeria. SUBJECTS AND METHODS: Children 5-20 years of age were enrolled from two rural villages. Height and weight were measured; body composition was estimated using bioelectrical impedance analysis. z-scores and centiles for height and body mass index were calculated; prevalences of low relative height (i.e.>2 standard deviations below mean for age and sex) and weight by sex and age were estimated. RESULTS: A total of 623 participants (326 male and 297 female) were enrolled. The mean height-for-age z-score for males younger than 19 years was -2.1 and prevalence of low relative height was 50%. Among females, the mean height-for-age z-score was -1.2 during adolescence; only 15% of adolescent females were of low relative height. Based on BMI-for-age, 37% of the adolescent males and 23% of females were underweight. No children or adolescents were overweight based on BMI-for-age. CONCLUSIONS: Low relative height and underweight occur in a large proportion of children and adolescents in rural Nigeria, with the lowest relative heights and weights occurring in mid-adolescence and among males.

Energy expenditure does not predict weight change in either Nigerian or African American women.

BACKGROUND: The relation between variation in interindividual levels of energy expenditure and weight gain remains controversial. OBJECTIVE: To determine whether or not components of the energy budget predict weight change, we conducted an international comparative study in 2 cohorts of women from sociocultural environments that give rise to the extremes of obesity prevalence. DESIGN: This was a prospective study with energy expenditure measured at baseline and weight measured annually for 3 y. Participants included 149 women from rural Nigeria and 172 African American women. The energy budget was determined by using respiratory gas exchange and doubly labeled water. Main outcomes included total, resting, and activity energy expenditure and physical activity level (ie, total energy expenditure/resting energy expenditure); baseline anthropometric measures; and annual weight change. RESULTS: Mean body mass index (in kg/m(2)) was 23 among the Nigerians and 31 among the African Americans; the prevalences of obesity were 7% and 50%, respectively. After adjustment for body size, no differences in mean activity energy expenditure or physical activity level were observed between the 2 cohorts. In addition, in a mixed-effects, random-coefficient model, interindividual variation in activity energy expenditure at baseline was unrelated to the subsequent pattern of weight change. CONCLUSIONS: These data suggest that interindividual levels of energy expended during activity do not have a large influence on age-related trends in adiposity. In addition, contrary to expectations, these data suggest that mean activity energy expenditure does not vary substantially between contemporary social groups with low and high prevalences of obesity.

Very low levels of energy expenditure among pre-adolescent Mexican-American girls.

We assessed activity energy expenditure (AEE) in Mexican-American (MA) and European-American (EA) children. Total energy expenditure (TEE) was measured using the doubly-labeled water method; AEE was calculated as the difference between TEE and resting EE (REE), and physical activity level (PAL) was calculated as TEE/REE. Groups were comparable for age, sex and body mass index (BMI). REE did not differ between groups. The boys did not differ in TEE, AEE, or PAL (MA vs. EA, respectively: TEE, 7.9+/-1.5 vs. 7.5+/-0.9 MJ x d(-1); AEE: 64.9+/-24.7 vs. 65.3+/-22.3 kJ x kg(-1) x d(-1); PAL: 1.57+/-0.18 vs. 1.58+/-0.19 kJ x kg(-1) x d(-1)). MA girls had lower TEE, AEE, and PAL than EA girls (TEE: 6.8+/-0.9 vs. 8.1+/-0.8 MJ x d(-1); AEE, 37.3+/-15.9 vs. 64.9+/-24.7 kJ x kg(-1) x d(-1); PAL, 1.40+/-0.12 vs. 1.57+/-0.18; P <0.005). Results suggest that these MA girls were expending less energy than EA children of comparable body size due to a reduced activity energy expenditure.

Energy expenditure and adiposity in Nigerian and African-American women.

OBJECTIVE: Obesity is a prevalent condition in industrialized societies and is increasing around the world. We sought to assess the relative importance of resting energy expenditure (REE) and activity EE (AEE) in two populations with different rates of obesity. METHODS AND PROCEDURES: Women of African descent between 18 and 59 years of age were recruited from rural Nigeria and from metropolitan Chicago. Total EE (TEE) was measured using the doubly labeled water (DLW) technique and REE by indirect calorimetry; AEE was calculated as the difference between TEE and the sum of REE plus a factor for the thermic effect of food. In the analyses all EE parameters were adjusted for body size using a regression method. Comparisons were made between the groups and associations between EE and adiposity examined. RESULTS: A total of 149 Nigerian and 172 African-American women completed the protocol. All body size measurements were lower in the Nigerian women. Adjusted TEE and REE were higher in the Nigerian cohort but adjusted AEE did not differ significantly. Adjustment for parity, seasonality, and recent illness did not modify mean AEE or adiposity. In neither cohort was there a meaningful association between measures of AEE and adiposity. DISCUSSION: In these cohorts of women from very different environments, AEE did not differ significantly nor was it associated cross-sectionally with adiposity. If generalizable, these findings suggest that reduction in AEE may have less of a role in the development of obesity than anticipated. The possibility remains that variation in type and duration of activity plays a role not captured by total AEE.