Contrary to the findings of a widely reported 2011 study indicating that binge eating affects men and women equally, most research on the subject shows that binge eating, like other eating disorders, predominantly affects women. Now a new study suggests that the difference may be biological.
The research, which appears online in the International Journal of Eating Disorders, showed that rats demonstrate binge eating patterns similar to those in humans, including the females' higher propensity to binge.
Kelly Klump and Cheryl Sisk, psychology professors at Michigan State University, conducted feeding tests with 30 male and 30 female rats, exposing them intermittently to Betty Crocker vanilla frosting instead of their usual food. The researchers identified bingeing rats as those who ate dramatically more frosting than their peers in a four-hour period. They found that lady rats were two to six times more likely to binge on the frosting than the male rats.
The findings are significant because "most theories of why eating disorders are so much more prevalent in females than males focus on the increased cultural and psychological pressure that girls and women face... this study suggests that biological factors likely contribute as well, since female rats do not experience the psychosocial pressures that humans do, such as pressures to be thin," Klump said in a press release.
Essentially, female rats don't have body image issues and haven't absorbed the "you can never be too thin" lore of previous generations of female rats. They have not been influenced by the media's unrealistic body ideal. When they binge, it has to be for different reasons.
The research is also valuable because the authors acknowledged that the way studies, including this one, define bingeing may skew the results. Past rat and human studies have looked specifically at the rapid intake of lots and lots of tasty, often high-fat carbs -- frosting or shortening for rats, doughnuts and cookies for humans-- which tend to be more appealing to females. Guess what hasn't been studied as much? Males consuming large quantities of protein-rich food -- the type of food they tend to prefer. So far that hasn't been considered bingeing, just having a manly quarterback breakfast.
In other words, the fact that a man is unlikely to put away an entire package of Oreos doesn't mean he doesn't have an eating disorder. If further research in humans revealed that some Double Whopper consumption was actually bingeing, the difference between rates of bingeing in men and women might be smaller.
Thanks for the insights, lady rats.