Although most nutritional research and intervention in the developing world has previously focused on poverty and undernutrition, there is growing evidence of a major shift toward overweight and obesity in some of these societies, a trend that is of special concern for children and adolescents because of the lifelong adverse health effects that are associated with overweight.

Publishing in the American Journal of Clinical Nutrition, Wang et al. used the same references across countries to examine trends of over- and underweight in older children and adolescents residing in the United States, Brazil, China, and Russia.

Over periods spanning 2-3 decades, the prevalence of overweight in children and adolescents tripled in Brazil, almost doubled in the United States, and increased by one-fifth in China.

In contrast, the incidence of childhood overweight declined by 7% in Russia during the 1990s. The authors examined societal and economic trends that may be responsible for increasing overweight among a large segment of the worlds population of young people.

The authors note that large portions of the populations of Brazil, China, and the United States have benefited from improved economic and social conditions in recent decades, whereas Russia faced severe economic setbacks during the 1990s.

Improvements in economic welfare have brought with them more secure food supplies, more energy-dense diets, and increases in inactive leisure time. Declines in physical activity are particularly associated with television watching, identified as a major cause of childrens inactivity and linked to childhood obesity in several studies.

In the United States alone, a significantly greater proportion of adolescents (27.3%) than children (22%) were overweight, and in China, increases in the incidence of overweight were more pronounced in males than in females.

At present, very few countries have taken a systematic approach to aggress
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Contact: Elizabeth Horowitz
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American Journal of Clinical Nutrition
23-May-2002