Is Obesity To Blame For Early Puberty In Girls?

Early puberty is on the rise, especially among girls. More girls develop breasts and start menstruating earlier, and American girls reach physical maturity sooner than they did only 30 years ago. 

Previously, girls were expected to show the first signs of puberty between the ages of eight and 14. Breast development before age eight or the onset of menstruation before age nine are currently considered early, and if you think that those girls are barely out of diapers, you wouldn't be wrong. What's behind this phenomenon of earlier and earlier puberty? Scientists have been trying to find out.

Obesity changes a young girl's hormonal cocktail and can trigger premature breast development and periods because her body thinks it is ready for the next stage. While there are definitely other potential causes of early puberty, childhood obesity rates are skyrocketing in the Western world, especially in the United States, and the possibility of an early puberty along with its related risks is yet another reason to take it very seriously. 

BMI 'The Strongest Predictor Of Early Breast Development'

The new study followed over 1,200 girls from age six to eight in three highly urban US areas: the San Francisco Bay Area, Greater Cincinnati, and New York City. The researchers followed the girls for seven years between 2004 and 2011 and monitored their pubertal maturation through well-established criteria during multiple visits. 

Does overweight or obesity actually cause an early puberty? The study's authors point out that their research does not establish that to be true, though it certainly seems likely when you take into account what's already known about the impact of obesity on hormones. The study authors write that "the obesity epidemic appears to be a prime driver in the decrease in age at onset of breast development in contemporary girls".

Frank Biro MD made it clear that his team's findings have important clinical implications, and that the study suggests that "clinicians may need to redefine the ages for both early and late maturation in girls". 

How Does Early Puberty Impact Girls?

It's already clear that an early puberty (by the current definition, that is) increases a girl's risk of developing diabetes, high blood pressure, and heart disease later in life. The early onset of menstruation also gives a girl a higher risk of developing breast cancer. 

Beside those physical health risks, anyone can see that being physically mature early on in life can lead to social and psychological problems too. These early birds may have breasts and the capability to become pregnant, but they're still kids, for whom even managing messy periods can be a real challenge. Being a kid in a mature body has got to be tough. Frank Biro MD put it like this:

Referencing earlier studies, the authors say that girls who go through puberty early on "are more likely to be influenced by older peers and more deviant peers, and initiate intercourse, substance use, and other norm-breaking behaviors at younger ages."

Parents of pre-pubescent girls might wonder if the new study has practical implications for their daughters. While the answer is not simple by any means, the common wisdom of making sure your children eat a healthy and balanced diet and exercise regularly still stands. A healthy BMI may well decrease your child's risk of an early puberty.

In addition, you may want to start talking about puberty and its social impact a whole lot earlier than you previously thought you should. Girls who get their first periods before they know what menstruation is can be terribly frightened, to the point where they think the blood means that they are dying. Even if your girl is only seven, it may be good to get some books about puberty, so she knows what's coming.