| Updated at: 1614 PST, Monday, November 22, 2010|
NEW YORK: The obesity epidemic has spread to poorer nations, where it almost entirely affects wealthy citizens, while the poor in the same nations still remain underweight, a study said.
By contrast, obesity tends to have a greater impact on the poor in developed nations, such as the United States.
"There's a lot of discussion on how the problems of obesity and overweight are now spreading to poor and developing countries," said S.V. Subramanian, at the Harvard School of Public Health, who led a recent study.
But the question of who is most affected within those countries is almost never asked, he told Reuters Health.
In the study, published in the American Journal of Clinical Nutrition, Subramanian and his colleagues looked for weight trends in more than half a million women in 54 developing countries between 1994 and 2008.
Overall, they found that just about a quarter of the women were overweight, with the rate varying widely between nations -- from three out of every four women in Egypt, to just 6 percent in Ethiopia.
More importantly, as levels of income and education rose, so did the weight of individuals. Those in the top quarter of wealth had more than twice the risk of being overweight compared to the bottom quarter.
Meanwhile, a substantial portion of the population -- often larger than the overweight portion -- still suffered from being underweight.
"On the one hand, you have populations where there is a need to increase calorie intake, and on the other, you have the rich folks who are overconsuming," Subramanian said.
Food is cheap and convenient for the well-to-do, and their neighborhoods typically house a lot of restaurants where people can eat while not expending energy to cook, he said.
Cultural phenomena, such as expectations that a marriage-aged girl should look healthy rather than anorexic, may also play a part, he added.
For the overweight, he suggested that intervention through the education and the media could help. The issue of the poor is more difficult, and simply providing more calories may not be the answer.
In Egypt, for example, the government subsidized trans fats and saw increased obesity in poor populations, along with continuing problems with underweight among those too poor to even buy the cheaper food.
"We should have a more comprehensive policy that focuses incentives on the right compositions of nutrients. That way we can solve the problem of underweight, while also controlling the problem of overweight," he said.