Obesity in U.S. girls is causing puberty to come earlier for the children, according to reports. Researchers studied the reason behind many young girls developing sooner and sooner, and found that a higher body mass index was the "strongest predictor" of breasts coming in earlier.
The U.S. obesity epidemic has caused the median age of girls developing breasts- 9.7 years old for Caucasian girls, studies showed- to increase four months since 1997. African-American girls' breasts are showing up even earlier, researchers said.
"The obesity epidemic appears to be a primiere driver in the decrease in age at onset of breast development in contemporary girls," the study, led by Frank Biro at Cincinnati Children's Hospital, revealed.
The study used 1,240 girls between six and eight from New York, San Francisco and Cincinnati with funding from the government's Breast Cancer and the Environment Research Program. Dr. Neerav "Nick" Desai, who isn't associated with the study, said there is no doubt about the conclusions.
"The numbers in this study are very precise," he told The Epoch Times. "It's more precise than any other."
Now researchers believe they may need to redefine the ages for early and late maturation, but others warn against early puberty becoming the "new normal"- development happening too soon could be signs of psychological and health issues.
"Because early puberty and menarche are associated with many detrimental health and psychosocial issues, we must not accept this premature development as the 'new normal,'" Dr. Marcia E. Herman-Giddens of the Gillings School of Global Public Health at the University of North Carolina at Chapel Hill, wrote in an accompanying editorial.
Nearly 17 percent of U.S. children and teenagers are obese, according to federal statistics.