When ultrathin teen celebrities prance about on TV and weight-loss secrets are teased on every magazine rack, it’s easy to blame pop culture for women’s troubled relationships with their bodies. And while there’s no doubt that media images and messages have an impact, new research indicates there’s something at work in the one place advertising has yet to infiltrate: the womb.
Researchers at Michigan State University have discovered that females who have an opposite-sex twin exhibit a lower level of eating disorders, closer to the male range, than females who have same-sex twins and females who grew up with similarly aged brothers, according to Science News (May 10, 2008). Hormonal exposure during gestation can affect fetal development, and at about 10 to 12 weeks, male fetuses begin to produce a robust blast of testosterone already credited with rendering their female twins more adventurous and aggressive. Extending this prenatal effect into the realm of eating disorders could radically shift how we conceive of women’s tendency to struggle with food, so often pinned on social pressures and slavish devotion to appearance.