Body mass index of adult males in 12 populations of Northeast India

Abstract

Background: Of the anthropometric indices, body mass index (BMI) is considered to be more nutritionally than genetically related. Thus, in a country with diverse ethnic groups like India, it is more appropriate to use BMI as an indicator of the nutritional status of adult population. However, literature on BMI of adult Indians is limited to certain geographical regions or populations, and little is known about the populations in the northeast region of the Indian sub-continent.Aim: The present report deals with the BMI of adult males in 12 populations of Northeast India with a view to understanding their nutritional status.Subjects and methods: Anthropometric data collected by the Anthropological Survey of India on 946 adult males aged 18-62 years of 12 populations in Northeast India were used in this analysis. The populations were broadly categorized into three groups, namely, caste, Hinduized and tribal groups. The data were collected mostly from rural areas, taking into consideration the different social ranks such as castes, tribes and religious groups.Results: The variation in mean BMIs between populations was highly significant, ranging between 18.3 and 20.5 kg m−2. Despite a few exceptions, the mean values of BMI in the tribal populations were significantly higher than the caste groups. The prevalence of chronic energy deficiency (CED) was also lower in the tribal (19%) than in the Hinduized (49%) and caste (52%) populations (χ2 = 89.4, d.f. = 2, p<0:001). Although it is difficult to explain why the tribals have higher BMI than the higher castes, the Cormic index or CI (SH/H) was significantly lower among the caste groups as compared with some tribal groups. The linear regression coefficient (b ± standard error) of BMI on CI for all the populations, irrespective of ethnic origin, was 30.4 ± 4.3 (t = 7.1, p<0.000), and the correlation coefficient (r ± standard error) 0.22 ± 0.03. The differences in BMI across groups were, however, significant even after allowing for CI.Conclusion: A majority of the adult males in these populations were lean. The high proportion of individuals with grade I CED suggests the need of other information on morbidity and health status of these populations.