Sad teen girl with scales on floor

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DURHAM, N.C. — Childhood obesity is a growing problem in the United States. As of 2016, the Centers for Disease Control and Prevention says nearly one in five children is obese. A new study finds this issue may also lead to developmental problems for girls entering adulthood. Researchers say obesity can throw off the timing of puberty in young girls.

A team from the National Institute of Environmental Health Sciences has discovered that overweight girls can have more testosterone in their bodies. This can lead to irregular periods, acne, and excess body hair. Researchers add that puberty looks different among obese girls in terms of breast growth and reproductive hormones.

According to previous studies, young, overweight females start puberty and experience their first menstrual period earlier than girls with a normal weight. However, it has not been clear if obesity can change not only the timing of puberty, but also a girl’s reproductive hormone levels too. This can impact how females develop reproductive organs such as breasts, ovaries, and a uterus.

“We found that in mid- to late puberty, girls with greater total body fat demonstrated higher levels of some reproductive hormones including follicle-stimulating hormone (FSH), inhibin B and male-like hormones such as testosterone,” study author Dr. Natalie Shaw says in a media release.

“In some girls with higher total body fat, higher testosterone levels were associated with irregular menstrual cycles, acne and excess body hair. In late puberty, girls with greater body fat also showed delayed breast maturation, as determined by breast ultrasound, and earlier menarche. There were no differences in maturation of the ovaries or uterus as a function of body fat.”

Obesity’s impact on maturity

Over a four-year period, researchers studied 90 girls between eight and 15 years-old. Thirty-six girls classified as being obese while the other 54 had a normal weight. The team calculated total body fat using a dual-energy x-ray absorptiometry (DXA) scan. The team also tracked puberty using the Tanner staging growth chart, breast and pelvic ultrasounds, measuring hormones levels in blood samples, and recording each girl’s age at her first period.

Their findings show that girls with higher total body fat had differences in their reproductive hormone levels. They also developed mature breasts more slowly and had their first period earlier than girls with lower total body fat.

“The long-term consequences of these differences in puberty markers deserves further study,” Dr. Shaw concludes.

The research appears in the Journal of Clinical Endocrinology & Metabolism.

SWNS writer Laura Sharman contributed to this report.

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