A study that examined the health records of over 8 million 5th, 7th and 9th graders in California from 2001 to the end of 2008 reveals that the prevalence of adolescent obesity has continued to increase for African-American and American-Indian girls. Most boys’ and non-Hispanic Caucasian girls’ obesity rates peaked in 2005, and then started to drop.

Only Asian youth’s and non-Hispanic white boys’ rates declined after peaking in prevalence of severe obesity.

The authors explain that while obesity may be dropping for some ethnic groups, this is not occurring among African-American and American-Indian girls.

The researchers said that their aim was to investigate trends in prevalence of high Body Mass Index (BMI) from 2001 to 2008, and to assess racial/ethnic variations.

They gathered data from 8,283,718 fifth-, seventh- and ninth graders who had undergone California’s school-based BMI screening during the 2001-2008 period.

The researchers found that:

  • Obesity rates continued to rise for African-American and American-Indian girls throughout the whole period
  • Obesity rates for Hispanic girls leveled off after 2005
  • Non-Hispanic Caucasian girls’ obesity rates peaked in 2005 and then dropped to 2001 prevalence levels
  • Obesity rates stayed the same for Asian girls
  • Obesity rates for non-Hispanic Caucasian boys peaked in 2005, and then dropped to 2001 levels
  • Hispanic and Asian boys’ obesity rates dropped after 2005, but stayed above 2001 levels
  • Obesity rates for American-Indian boys peaked in 2007

The authors concluded:

On the basis of statewide California data, prevalence of high BMI is declining for some groups, but has not declined for American Indian and black girls. These trends portend greater disparities over time, particularly in severe obesity. Interventions and policies that are tailored to the highest risk groups should be pursued.

“Disparities in Peaks, Plateaus, and Declines in Prevalence of High BMI Among Adolescents”
Kristine A. Madsen, MD, MPH, Ashley E. Weedn, MD, Patricia B. Crawford, DrPH, RD
PEDIATRICS August, 2010. doi:10.1542/peds.2009-3411

Written by Christian Nordqvist