After reading about a new brain imaging study suggesting that they have a tougher time controlling their hunger than males, women could be forgiven for throwing up their hands in frustration. Ladies, don't worry; this study does not mean that because of your gender, you're physically incapable of turning your back on Ben & Jerry. And men, don't be smug; neither does it mean you all have an iron will when it comes to food.
As part of the study, which appears in the Proceedings of the National Academy of Sciences, researchers used PET scans to track brain activity in 23 volunteers. They wanted to see what areas of the brain were working when subjects had their favorite foods in front of them. They also monitored volunteers' brains when shown the same foods after being told to tamp down their desires. What researchers found is that the areas of the brain involved in the desire to eat lit up in both sexes when hungry and exposed to favorite foods. But when told to rein in their response, the men's brains, on average, showed less activity in those food-related areas. Women's brains, on average, were still active.
Those differences, say study authors, may offer clues as to why women have a harder time with weight loss and suffer disproportionately from eating disorders. (Sex hormones may be involved with the differences, but that's just a theory.) Because these volunteers weren't obese, further research is also needed to see if the brains of obese men and women differ from those of thinner peers. "We need to piece this together like a puzzle," says Gene-Jack Wang, lead author of the study and a scientist at the Brookhaven National Laboratory in Upton, N.Y.
But like other brain imaging studies looking at sex differences, these findings are based on averages. Some female brains behave more like males'-they're able to cognitively inhibit appetite, in this case—and vice versa. "What is true on average for women isn't necessarily true for every woman," says Ruben Gur, director of the Brain Behavior Laboratory at the University of Pennsylvania School of Medicine. "We know men are taller than women, for example, but if you put Martina Navratilova next to Robert Reich, you wouldn't see that."
Unlike height, though, it's not possible to look at a person and know if their brains are acting similarly to most others of their gender. "The ironic implication is that you must treat each individual to estimate their strengths and weaknesses," says Richard Haier, professor emeritus at the University of California-Irvine, who has studied gender differences in the brain.
So while this kind of study may open the door to further research on how males and females differ when it comes to eating, and even to potential drug or other treatments for eating problems, it doesn't mean you're necessarily fated to give in to that Twinkie. Rather than fret about your hard wiring, figure out how to find a healthful lifestyle that works for you: Check out these five tips for boosting willpower, follow a sensible, balanced diet, and try out seven tips to get plenty of exercise (here are 7 tips to help).