Here's a crazy statistic for you: In the United States, from the mid-1800s through the 1960s, the average age for a girl's first menstruation dropped quickly and steadily -- by an average of four months every decade. This was across the board with every social, economic, racial and ethnic group.
It's gets weirder: According to a startling new medical study, puberty is now kicking in as young as age six for some African-American girls in the U.S. What is going on? And what are the dangers of early puberty? Trace Dominguez investigates in today's DNews report.
According to the National Institutes of Health, puberty used to start in the late teen years for most kids up through the 19th century. Today, the average age range is 8 to 13 for girls and 9 to 14 for boys. No one really knows why this is, but it's certainly not for lack of research. Hundreds of theories have been proposed over the years regarding nutritional, psychological and environmental factors, but nothing conclusive has been established.
We might not know what's causing early puberty, but we do know something about the effects. When puberty starts especially early like -- before age 7 or 8 for girls, or age 9 for boys -- it's called precocious puberty, and it can cause all sorts of problems.
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For one thing, it can make you shorter. Studies show that when kids hit early growth spurts via precocious puberty, the bones' growth plates don't work properly during later development periods, resulting in shorter stature in adulthood. Precocious puberty has also been correlated with type-2 diabetes, adult-onset asthma and even breast cancer.
Even more worrisome are the psychological factors. Early onset puberty puts kids at a higher risk for stress, depression and a number of associated issues. Studies suggest it can cause children to become sexually active at a younger age and lead to eating disorders or addiction problems.
Which makes a sad kind of sense: Early puberty bumps the body into physical maturity before the brain is ready to handle it. As puberty continues to kick in earlier, psychologists recommend that parents be mindful of these issues and keep lines of communication open. Click around online and you can find plenty of resources for helping families navigate the specifics of precocious puberty.
-- Glenn McDonald
National Library Of Medicine: Early Life Circumstances And Their Impact On Menarche And Menopause
New York Times: Puberty Before Age 10: A New 'Normal'?
Scientific American: Early Puberty: Causes And Effects