While the global economy sputters to a tepid recovery, the growing menace of obesity in the developing world is barely noticed. In a recent estimate, out of 1.1 billion overweight adults worldwide, 312 million are obese. Together with underweight and the stunting of children, the paradox of the dual burden of households—in which the children are underweight and the adults are overweight—poses a major health challenge for millions of households.

In the last two decades, rates of obesity have tripled in the developing world. Even among children, the prevalence rates of overweight and obesity have risen.

Illustration: Jayachandran / Mint

The fundamental cause of overweight and obesity is an energy imbalance between calories consumed and calories expended. This imbalance is due to (i) a global shift in diets towards a higher intake of energy-dense foods that are high in fat and sugars but low in vitamins, minerals and other micronutrients; and (ii) a reduction in physical activity due to the sedentary nature of work, better modes of transportation and urbanization.

The upsurge in the numbers of the overweight and obese portends higher risks of chronic non-communicable diseases (example, hypertension, diabetes, cardiovascular disease and cancer). The burden of chronic diseases has risen sharply in India, accounting for 53% of all deaths and 44% of disability-adjusted life years in 2005. Worse, many of these deaths occur at early ages. In fact, the number of potentially productive years lost due to deaths from cardiovascular disease in the age group of 35-64 (9.2 million years lost in 2000) is the highest in the world. By 2030, it is expected to touch 17.9 million years.

A recent household survey conducted jointly by the University of Maryland and the National Council of Applied Economic Research—India Human Development Survey 2005—allows an assessment of overweight and obesity, and their implications for chronic non-communicable diseases. We first provide a summary of the findings on the prevalence of overweight and obesity among the adults (older than 22 years).

• About 9.5% of the adult males were overweight and about 2.5% were obese. The corresponding rates among adult females—12.65% and 3.18%, respectively—were higher.

• While overweight and obesity are largely an urban phenomenon— about 22% of the adults were overweight and about 7% were obese— these disorders are observed in urban slums and rural areas too. Specifically, the proportion of overweight in urban slums (about 15%) was lower but not markedly so. In the rural areas, however, the proportion of overweight (above 9%) was a little less than half of that in the urban areas, and that of obese (about 2%) was just over one-fourth of the figure in urban areas.

• Overweight and obesity are not confined to relatively affluent households. Although lower among the poor, their proportions are non-negligible. Our analysis shows that, among the non-poor, the proportions of overweight and obese were about 14% and just under 4%, respectively. Among the poor, the shares were 7% and about 1.25%, respectively.

• Disaggregation of the overweight and the obese by caste and tribe further suggests that even socially and economically deprived sections are not immune to such disorders. Among the scheduled castes, the proportions of overweight and obese were about 9% and a little less than 2%, respectively; among the scheduled tribes, the proportions were slightly lower—about 6% and above 1%, respectively; among the other backwards castes, the corresponding estimates were above 12% and about 3%, respectively; and among the remaining, the estimates were the highest—above 17% and about 5%, respectively.

• Finally, there was a sharp increase in the proportions of the overweight and obese over the period from 1998 to 2005. The proportion of the overweight more than tripled while that of the obese rose at least six times.

Turning to the risks of non-communicable diseases, there are significant variations by disease, age and gender. A few illustrations suffice. Among those suffering from high blood pressure, about 46% were either overweight or obese. Among females in the 23-45 age group, about 44% of those who were overweight and obese suffered from high blood pressure. In the older age group (those older than 45), the proportion was as high as 56%. Among males older than 45 years, about 57% of the overweight suffered from diabetes while among the females, the proportion was much lower, at 48%.

In conclusion, while concerns for poverty and hunger must dominate the policy agenda, the options for dealing with obesity and the upsurge in non-communicable diseases can only be neglected at the peril of millions of lives that may suffer their worst consequences. Although shifts in diet and physical activities are desirable in many ways—arguably varied and pleasurable—it will be a mistake to overlook the onerous nutritional health effects and the tragic but avoidable loss of well-being.

Raghav Gaiha is a professor of public policy at the Faculty of Management Studies, University of Delhi; Raghbendra Jha is the Rajiv Gandhi chair professor of economics at the Australian National University; and Vani S. Kulkarni is a lecturer in South Asian studies at Yale University. Comment at theirview@livemint.com