Disparities in Peaks, Plateaus, and Declines in Prevalence of High BMI Among Adolescents

While obesity rates have declined for California’s White and Asian youth since 2005, rates have leveled off or increased for other ethnic groups.

Recent National Health and Nutrition Examination Survey (NHANES) data suggest some leveling off in childhood obesity rates from 1999 to 2008. But, the data do not address trends for different races and ethnicities. California’s mandated school-based BMI screenings, however, offer a look at disparities in youth prevalence of obesity among five racial/ethnic groups—Hispanic (46.4%), non-Hispanic White (32.8%), Asian (12.6%), Black (7.7%) and American Indian (.5%).

The vast amount of data collected from 2001 to 2008 includes records for more than 8 million students in 5th, 7th and 9th grades, representing 69 percent of all students enrolled. Overall, 38 percent of youth were overweight, including 19.8 percent obese and 3.4 percent severely obese.

For most boys and White girls, the prevalence of high BMI peaked in 2005. Hispanic girls, however, showed no decline after peaking. Black and American Indian girls continued to increase across three of four BMI categories through 2008. These differing patterns of plateaus rather than declines in BMI suggest racial and ethnic disparities in the prevalence of high BMI and temper otherwise encouraging declines in obesity with concerns about increasing disparities. Policies and interventions need to be tailored to reach the identified high-risk populations.