Obesity May Trigger Earlier Puberty for Girls

Breast development at 9 linked to weight gain in younger years, study finds

MONDAY, March 5 (HealthDay News) -- Childhood obesity may lead to earlier onset of puberty for girls, a U.S. study concludes.

The study of 354 girls from 10 different regions in the United States found that increased body fat in girls as young as age 3 and large increases in body fat between the age of 3 and the start of first grade were associated with earlier puberty, defined as the presence of breast development by age 9.

"Our finding that increased body fatness is associated with the earlier onset of puberty provides additional evidence that growing rates of obesity among children in this country may be contributing to the trend of early maturation in girls," study lead author Dr. Joyce Lee, a pediatric endocrinologist at the University of Michigan, said in a prepared statement.

Her team published the findings in the March issue of Pediatrics.

Lee noted that girls in the United States are entering puberty at younger ages than they were 30 years ago. Over that same time, there's been a significant increase in obesity rates among American children.

"Previous studies had found that girls who have earlier puberty tend to have higher body mass index (BMI), but it was unclear whether puberty led to the weight gain or weight gain led to the earlier onset of puberty. Our study offers evidence that it is the latter," said Lee, who is also assistant professor in the department of pediatrics and communicable diseases at the U-M Medical School.

"Beyond identifying how obesity causes early puberty, it's also important to determine whether weight control interventions at an early age have the potential to slow the progression of puberty," she noted.