Researchers are reporting a possible hormonal link to eating disorders that develop during puberty from a type of estrogen called estradiol. A study found that the influence of genes on eating disorder symptoms was much greater in girls going through puberty who had higher levels of the hormone estradiol, than with girls with lower levels.

Previous research had established that eating disorders are influenced by both genetic and environmental factors once a girl hits puberty. The underlying effects of the genes, however, were unknown.

“The reason we see an increase in genetic influences during puberty is that the genes for disordered eating are essentially getting switched on during that time,” said lead researcher Kelly Klump—an associate professor of psychology at Michigan State University—in a release. “This research was trying to figure out why. What’s turning on the genes during puberty? And what we found is that increases in estradiol apparently are activating genetic risk for eating disorders.”

Her group’s research looked at the estradiol levels of nearly 200 sets of female twins, ages 10 to15. The findings are published in Psychological Medicine.

Estradiol is the predominant form of estrogen and is responsible for the growth of reproductive organs and influences other organs including bones. Knowing that estradiol likely plays a role in eating disorders could ultimately open the window to new treatments, said Klump. In addition, she said, prevention efforts could be geared toward girls who not only are in high-risk environmental contexts (such as weight-focused sports), but also have genetic risks such as a family history of eating disorders.

In the May 2010 issue of Best Health (on newsstands until June 13), writer Erin Phelan talks about her personal battle with an eating disorder and her efforts not to pass this on to her daughter.
Have you or someone in your family had to deal with an eating disorder?