A new study finds little girls are maturing faster. 10 percent of white seven year old girls have begun puberty, according to the study from Cincinnati Children's Hospital conducted in the mid 2000s, which is five percent higher than in the early 1900s. The trend is happening across all race groups.
"It does seem like girls are hitting puberty earlier than previous generations," said Dr. Jay Maust, pediatrician at The Southwest Louisiana Children's Clinic.
The study found 42 percent of African American girls have started puberty by age eight and Dr. Maust said it may be for a good reason.
"Better nutrition in some cases helps the body grow taller earlier and go through maturation earlier," said Maust.
While a healthy diet is good, long term effects from early puberty can be life threatening.
"Their bodies for a longer period of time are subjected to hormonal control at an earlier age and over the long term that can increase the risk of certain female cancers like breast cancer," said Dr. Maust.
The study looked at 1,400 girls, but many experts are still puzzled why maturation is speeding up.
"I don't know either it's still up for study and debate," added Dr. Maust.
Childhood obesity is one theory. Preliminary research also show family stress could play a role. Another theory is that environmental toxins may trigger hormones and now the NIH is funding a massive study including 100,000 girls that will be tracked from birth through age 21.