Study Shows: Childhood Obesity, Early Puberty Linked

Childhood obesity in the United States appears to be causing girls to reach puberty at an earlier age, for reasons that are not clear, a study said on Monday, according to Reuters.

The University of Michigan's Mott Children's Hospital said a study following a group of 354 girls, for multiple years, found that children who were fatter at age 3 and who gained weight during the next three years reached puberty, as defined by 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 many be contributing to the trend of early maturation in girls" said Dr. Joyce Lee, the lead author. "Previous studies had found that girls who have earlier puberty tend to have higher body mass index, 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"

There have been earlier studies showing that U.S. girls are reaching puberty earlier than girls reached puberty 30 years ago. The 30 year time span is the same time span in which childhood obesity has increased.

In the study girls were classified as at risk for being overweight if their body mass index (measurement of weight related to age and height) was between the 85th and 95th percentiles, and defined as overweight if the measurement was greater than the 95th percentile.

Researcher said that 168 of the girls in the study were classified as being "in puberty" by the age of 9 and nearly two dozen reported having their first menstrual period by two years later.

"Earlier onset of puberty in girls has been associated with a number of adverse outcomes, including psychiatric,disorders and deficits in psychosocial functioning, earlier initiation of alcohol use, sexual intercourse and teenage pregnancy and increased rates of adult obesity and reproductive cancers: the study said, as reported by Reuters.

The study was published in Pediatrics, the Journal of the American Academy of Pediatrics.