Transitioning to an obese India: Demographic and structural determinants of the rapid rise in overweight incidence.

India, which has long suffered from undernutrition, has seen a rapid rise in overweight incidence in the last decade and a half. These changes are characterized by significant within-country differences in overweight incidence that vary by gender and regional development levels. In this paper, we provide an integrative framework, linking the income-gradient hypothesis of obesity with biological, obesogenic, and environmental factors to provide an explanation on the emergence of within-country differences in overweight patterns. We utilize measured body mass index (BMI), along with individual- and household-level data of over 800,000 men and women surveyed in the National Family Health Surveys of 2005-06 and 2015-16 to identify correlates of within-country differences in overweight incidence. A decomposition analysis reveals that among women, in addition to increasing access to obesogenic technologies, biological factors are associated with overweight incidence. Among men, obesogenic factors related to technology use and health behaviors are associated with the rise in overweight incidence, but biological factors are not. At lower levels of regional development, overweight incidence is associated with greater access to obesogenic technology such as motorized transport, which reduces physical activity among men at higher rates than women. At higher levels of economic development, obesogenic behaviors, such as watching more television and reducing smoking, are associated with overweight incidence. Our results corroborate the call by public health experts for group-specific policies to stem the rise of overweight incidence in developing countries.