Obesity: does it occur in African children in a rural community in South Africa?

Background Total body fatness and a centripetal fat patterning are recogniz ed as risk indicators of cardiovascular disease in adulthood. In this study , the development of these risk factors in rural South African children dur ing the preschool years and first years of formal schooling is explored. Method The initial cross-sectional data from the Ellisras Longitudinal Inve stigations in Rural Community Children Project, ongoing since 1996, were us ed, involving 684 boys and 652 girls, aged 3-10 years, in the Ellisras rura l community. Overweight was measured using the body mass index (BMT) (kg/m( 2)). Overfatness was based on the sum of the triceps and subscapular skinfo ld thicknesses. A centripetal fat patterning was measured by the sum of tru nk skinfolds relative to limb skinfolds and the ratio of the subscapular to triceps skinfold. Further, the ratio of the subscapular to supraspinale sk infold was used as an indicator of lower body fat patterning. The 85th perc entiles of the NHANES III were used as cutoff values for overweight, overfa tness and a centripetal fat patterning. Results At ages 7 and 8 years, mean BMI was statistically significantly hig her in males compared to females (P < 0.05). The log transformed supraspina le skinfold thickness was larger in females compared to males at ages 4-7 y ears; the log transformed subscapular skinfold was larger in girls compared to boys aged 7-10 years. Less clear patterns were found for the extremity skinfolds and the skinfold ratios. Very few children (0-2.5% in males and 0 -4.3% in females) had BMI values above the NHANES III 85th percentiles, ind icating a very low prevalence of overweight children in the area. About 15% of the males showed overfatness at ages 3-4 years, while low prevalence wa s found at older ages. Conclusion Few Ellisras rural children had above normal values for BMI, ind icating a low prevalence of obesity in this population. In the 3- and 4-yea r-old group more subjects were found to have excessive fat, as indicated by the sum of the triceps and subscapular skinfold thicknesses.