Although the prevalence of high BMI has recently declined in children
and adolescents, disparities in BMI are still observed in several racial/ethnic
groups, particularly black and American Indian girls.
Researchers examined data on more than 8,000 fifth-, seventh- and
ninth-grade students who underwent school-based BMI screening in California
from 2001 to 2008. High BMI cut points used were the 85th, 95th 97th and 99th
percentiles or higher.
When the researchers examined the prevalence of high BMI among girls,
they found:
- Black and American Indian girls had increases in three of the four
BMI cut points.
- Hispanic girls experienced an increase followed by a plateau after
2005.
- White girls’ prevalence increased from 2001 to 2005 before
declining to 2001 rates.
- Asian girls experienced no change.
Disparities were also observed in boys:
- White boys experienced an increase through 2005 following by a
decline to 2001 for all cut points.
- Hispanic and Asian boys’ levels declined after 2005 for the
three lowest BMI cut points but levels remained greater than 2001 levels.
- American Indian boys had a decline in only the 95th percentile cut
point after 2007.
No declines were observed in children of any racial/ethnic group with a
BMI cut point of the 99th percentile or greater. According to 2008 screening
results, children with the 99th percentile or greater BMI cut point had the
greatest disparities in prevalence (4.9% for American Indian girls and 4.6% for
black girls vs. 1.3% for non-Hispanic white girls).
“To our knowledge, this is the first study to document a
population-based decline in prevalence of high BMI after 2005, among most boys
and for white girls,” the researchers wrote. However, “the
encouraging first signs of a decline in the obesity epidemic are tempered by
concerns about increasing disparities.”