Distribution and Determinants of Body Mass Index of Non-smoking Adults in Delhi, India

Data on height and weight of 3,428 non-smoking healthy adult subjects, obtained during an earlier community-based study in Delhi, India, on chronic respiratory morbidity due to ambient air pollution was analyzed to study the distribution of body mass index (BMI) and its determinants among adults in Delhi. The sample was drawn by systematic sampling from rural and urban areas of Delhi. In urban areas, the sampling frame was restricted to areas around air quality-monitoring stations. However, the areas were spread across the city and reflected wide economic spectrum. Subjects were classified as underweight, normal, overweight, and obese as per the criteria of the World Health Organization for BMI. The mean BMI of the entire sample was 22.14 +/- 4.61. It was higher among females, urban residents, and the higher-income group. Overall, 49.7% of the 3,428 subjects had a normal nutritional status, 24.8% were underweight, 19.4% overweight, and 6.1% obese. The prevalence of underweight was higher in rural areas (38.5%) and among the lower-income group (39.9%), while overweight and obesity were more common in urban residents (22.7% and 7.5% respectively), among females (21.7% and 7.7%), and the higher-income group (31.8% and 11%) (p < 0.05). The adjusted odds for underweight were 2.02 for rural subjects and 4.00 for the lower-income group. For overweight or obesity, odds were 5.6 for the higher-income group, 3.62 for urban residents, and 2.5 for females. It was concluded that problems of both underweight and overweight and obesity exist among the adults of Delhi. While females, residents of urban areas, and economically-better-off were more likely to be overweight or obese, residents of rural areas and those from lower-income groups were more likely to be underweight.