Childhood obesity rates leveling off

The latest data from the National Health and Nutrition Examination Survey show that the overall prevalence of obesity in children may be leveling off at about 17%, in contrast to the rapid increases seen in the 1980s and 1990s. Another study showed that availability of junk foods had little effect on weight gain in middle-school children.

In a sample of 4,111 children and adolescents from birth through 19 years of age, the prevalence of obesity did not change significantly between 2007-2008 and 2009-2010. In 2009-2010, 9.7% of infants and toddlers aged from birth to 2 years had high weight-for-recumbent length (ie, ≥95th percentile, based on Centers for Disease Control and Prevention [CDC] growth charts). Among children and adolescents aged 2 through 19 years, 16.9% were obese (ie, body mass index [BMI] at or above the 95th percentile on the CDC’s 2000 BMI-for-age growth charts).

Significant differences by race or ethnicity were found: Hispanic children and adolescents and non-Hispanic black children and adolescents were more obese than non-Hispanic white children and adolescents. Mexican American infants and toddlers were more likely to have high weight-for-recumbent length than non-Hispanic whites.

Differences between boys and girls were also found. Between 1999 and 2000 and 2009-2010, the prevalence of obesity increased in boys aged 2 to 19 years but not in girls. BMI also increased significantly in boys aged 12 to 19 years but not in girls or other age groups.

Sales of competitive foods (ie, foods such as soft drinks and sugary or salty snacks that compete with traditional school foods) have been cited as a contributing factor in childhood obesity, and this has led to efforts to restrict their sales in schools. Data from the Early Childhood Longitudinal Study, Kindergarten Class of 1998-99, however, showed no increase in the percentage of students in fifth and eighth grades who were overweight or obese despite availability of junk food in the school.

The findings suggest that children’s food preferences habits are established before adolescence and that efforts to promote healthy eating habits must reach beyond schools into home and community settings.

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