Study Suggests Obesity May Delay Boys' Puberty

Obesity trends may further widen the gap between boys' and girls' maturity.

ByABC News
February 1, 2010, 5:18 PM

Feb. 2, 2010— -- Researchers may have found yet another reason not to let boys become obese -- it could delay their puberty.

A study following over 400 boys shows that those who are obese are twice as likely as their normal-weight counterparts not to have started puberty by the age of 11 and a half. While previous studies in girls had shown the opposite phenomenon -- girls who are obese tend to hit puberty earlier than their normal-weight counterparts -- it seems obesity may cause a maturity delay in boys, a situation with unknown and possibly far-reaching effects.

"With the epidemic of childhood obesity, there's concern this is going to have a negative effect on growth and development," said Dr. Joyce Lee, a pediatric endocrinologist at the University of Michigan and the study's lead author.

Lee said that while girls have been well studied when it comes to the effects of early obesity, "there was a paucity of studies in boys."

In the new study, which was published in the Archives of Pediatric and Adolescent Medicine, it was found that 14 percent of obese boys had not started puberty by the end of the study, while only 7 percent of normal weight boys had not.

"This could add a further burden to obese, adolescent boys," said Dr. David Ludwig, director of the obesity program at Children's Hospital in Boston. "For [a boy] that may already be teased because of his appearance, delayed puberty could further increase the stigmatization."

He said that while the findings of this study are new, they confirm an observation some had made when working with obese boys.

"It may not be a well-recognized phenomenon but it is one that had been considered previously," Ludwig said.