If you're a man, how much you eat may have more to do with the gender of your dining companions than your appetite. A new Cornell University study, published in the journal Evolutionary Psychological Science, found that men will eat significantly more food in the company of women than they will with other men.

For the study, researchers observed 105 adults lunching at an all-you-can-eat Italian buffet over the course of two weeks. They recorded the number of pizza slices and how many bowls of salad each diner ate. Gender of each diner's eating partner or partners was also noted. Before leaving the restaurant, the diners were intercepted by a researcher to ask them to complete a short survey indicating their level of fullness after eating, and their feelings of hurriedness and comfort while eating.

Men who dined with at least one woman ate 93% more pizza and 86% more salad than men who dined with only other men. The amount that women ate didn't differ when eating with other women or with men. When they ate with men, many women indicated feeling that they overate and were rushed through their meal.

"These findings suggest that men tend to overeat to show off - you can also see this tendency in eating competitions which almost always have mostly male participants," explains lead author Kevin Kniffin, PhD, of Cornell University. The study was conducted by Kniffin, Ozge Sigirci, a former visiting scholar at the Cornell University Food, and Brand Lab and Brian Wansink, professor and director of the Food and Brand Lab.