The increased prevalence of obesity in Black females is present during childhood, and the prevalence of obesity is increasing faster in Black girls than in white girls. Recent data from the third National Health and Nutrition Examination Survey (NHANES III) showed that during preadolescence, age 6-11 years, 30.7 percent of Black girls, compared with 22.0 percent of white girls, were overweight. Furthermore, over the past 30 years the prevalence of obesity in this preadolescent age group has increased 150 percent in Black girls compared with 40 percent in white girls. The prevalence of obesity in the adolescent age of 12 to 17 years is similarly high, at 29.9 percent in Black girls compared with 20.7 percent in white girls. The 35 percent increase in obesity over the past 30 years is similar in the preadolescent and adolescent age groups for white girls, but for Black girls the increase is greater in the younger age group (150 percent more prevalent) than in the older age group (80 percent increase) .