We examined the association between Body Mass Index (BMI) and all-cause mortality in South Africa, using longitudinal data for the five waves of the South African National Income Dynamics Study. We found that Hazard ratios for all-cause mortality were significantly lower in the BMI range 25–40 kg/m2 in comparison with the reference category of 18.5–25 kg/m2 and were minimal in the range 30–35 kg/m2 (HR = 0.68, 95% CI: 0.50–0.88). BMI < 18.5 kg/m2 was associated with an increased risk of death, with a maximum hazard ratio of 2.14 (95% CI: 1.36–3.4) in the <16 kg/m2 category.
These results suggests that, in the South African adult population, BMI in the overweight or mild obesity range according to international definitions is associated with a reduced risk of mortality compared to the” healthy weight” range. Further research is needed to corroborate these results.
Read the article on Global Epidemiology.
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