By LUMA MUHTADIE
Globe and Mail Update
With the economies of the world's poorer countries continuing to grow, so are their citizens' waistlines.
A new study has found that obesity is no longer a health crisis confined to rich nations, such as the United States, Britain, Australia and Canada � now even people in poor countries are packing on the pounds.
Health experts have long known that in affluent countries where food is readily available, obesity prevails among the lower socio-economic groups.
But the reverse used to be true in poorer countries, because only the rich could afford to eat enough food to get fat.
"Our new work documents a major shift in the burden of the disease," said Dr. Barry M. Popkin, a professor of nutrition at the University of North Carolina at Chapel Hill and one of the study's researchers.
He said that even among developing nations never thought to have an obesity problem, the poor and poorly educated are beginning to bulge.
The study, a collaborative effort between scientists at UNC and the University of Sao Paulo in Brazil, analyzed data from roughly 149,000 women aged 20 to 49 in 37 countries. Data were standardized to consider the weight of women in various social classes relative to the wealth of their countries of residence.
The study found that in lower-middle income countries, women's obesity tended to increase systematically with family income.
More specifically, belonging to the lower socioeconomic group in a low-income country � one with a per capita gross national product (GNP) of less than $745 (U.S.) � conferred a strong protection against obesity. But as the country's GNP per capita rose to $2,995 or higher, women in the lower socioeconomic group entered the risk zone for obesity.
(GNP per capita is defined as the dollar value of a country's final output of goods and services in a year divided by its population, and reflects the average income of a country's citizens.)
The researchers suggest one possible reason for the trend is that after a certain level of economic growth � usually the product of greater industrialization � food becomes more available and high energy expenditures drop.
With increased industrialization and trade, highly processed foods, such as white bread and Kraft Dinner, become more available and affordable than fresh, energy-dense fare, such as fruits and vegetables, whole grains and lean meats.
The poor also tend to be less educated about nutrition and health.