Women Crave For Food More Than Men

By Margarita Nahapetyan

According to a new research on the brain, women unconsciously find it much harder to suppress their cravings for food and resist their favorite meals than men, and are more likely to give in to temptation.

Brain scans of hungry volunteers have been performed and scientists were able to compare the brain ability of men and women to check if gender was the reason that influenced the ability to resist hunger. 23 healthy volunteers (13 women and 10 men) were asked to fast for about 20 hours. Afterwards they were offered a plate of their favorite food, including hamburgers, lasagna, ice cream, bacon and egg sandwiches, pizza, fried chicken and chocolate cakes. During scanning, participants could see and smell the food. They even were allowed to taste it when a cotton swab was applied to their tongues. Some dishes were warmed up to make them more tempting and the new hot food was brought in every four minutes. But subjects were not allowed to eat anything until the 30-minute scans were done, and only after that they were asked to try to suppress the hunger and were suggested to think about anything that was not related to food.

Dr. Gene-Jack Wang, MD, who led the study at Brookhaven National Laboratory in New York, then monitored brains of the participants using PET (positron emission tomography) scans. What he found was that both men and women were successful in making themselves feel less hungry by suppressing their desire to eat. But the brain scans showed that when men tried to suppress their hunger, the parts of their brains which deal with the desire to eat were much less active than before, while women's brain patterns were still acting when they were hungry. Although some women were better than some men at suppressing their crave for food, on the whole the women's brains showed just as much hunger-related activity when they tried to hold down their desire. To be short, the women might have thought they were less hungry, but their brains suggested the opposite.

"We tried to understand how you can reduce food stimulation so we designed a study that asked people to use their brain power to reduce the stimulation of food, to reduce their craving for food - using real food," Dr Wang said. "Even though the women said they were less hungry when trying to inhibit their response to the food, their brains were firing in the regions that control the drive to eat. In contrast, men's brain activity decreased with their self reports of hunger during the scan when they were asked to keep hunger in check. This may indicate a gender difference in the ability to perceive and respond to internal body signals." Such differences may explain why women have a greater tendency than men to over-eat when tempted by tasty food or under emotional distress, Dr Wang has added.

Rexford S. Ahima, MD, PhD, director of the obesity center at the University of Pennsylvania's Institute for Diabetes, Obesity, and Metabolism, suggests that female sex hormones might play a major role. "There is a link between female hormones tending to promote weight gain and overeating," Ahima says. "There are some women who tend to binge eat in sync with their menstrual cycles. And look at pregnancy - it makes some women overeat, but some do not. So while there may be overall differences in terms of gender, this may differ for individuals."

Sex hormone, named estrogen, is known to affect appetite, food consumption and distribution of body fat. Women have proportionately more body fat than men do. It is believed that fat serves as a store of energy for pregnancy and lactation.

Dr Wang also brought to our attention that it is possible that during human evolution appetite suppression would have been more dangerous for women than for men, and therefore women find it harder to suppress a desire for food. "There could be evolutionary needs for that, because women have a very important mission: They have to carry the baby," says Wang. "And for most of human history, you could never get enough food to eat. Now that's no longer a problem in developed countries - but now this brain circuit is a problem when we are surrounded by attractive, high-calorie foods."

The solution, according to the scientist, for people who are unable to resist the temptation of food intake, is to stick at least to low-calorie foods.

"Our lifestyle now is so much different from that of our grandparents," Wang says. "Our jobs and our living status is very stressful. So when we see food we eat it, because we want to do something to compensate for our problems. Inhibition control is very important - but if you can't have it, surround yourself with nutritious foods."

The study appears in the latest issue of the Proceedings of the National Academy of Sciences. It was funded by the General Clinical Research Center of Stony Brook University, the National Institute on Drug Abuse and the National Institute on Alcohol Abuse and Alcoholism.