"College education and income levels [of the parents] can play a role in the amount of physical activity a person gets," he added.
The authors noted that the black girls began menstruating earlier than the whites, which could also influence weight gain.
Encouraging black teen girls to exercise is still important, but different approaches may be needed to prevent obesity in black girls, the authors said.
"Our findings require replication before any real recommendations can be made," White said. "They do, however, suggest that black girls should be particularly attentive in controlling their caloric intake."
To learn more about obesity and black Americans, visit the U.S. Office of Minority Health.
SOURCES: Pete McCall, exercise physiologist, American Council on Exercise, San Diego; James White, Ph.D., researcher, University of Bristol, England; June 2012, Archives of Pediatric and Adolescent Medicine
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