A 2016 study published in the Journal of Evolutionary Psychological Science found that men eat significantly more food in the company of women than they will with other men. The author of the study suggests that men overeat to show off, similar to an eating competition mentality.
Researchers observed 105 adults lunching at an all-you-can-eat Italian buffet with pizza and salads over the course of two weeks. Post-meal, diners were intercepted by a researcher to ask them to complete a short survey indicating their level of fullness after eating, in addition to their feelings of hurriedness and comfort while eating. Men who dined with at least one woman ate 93% more pizza and 86% more salad (well, at least they had salad…) than men who dined with only other men. The amount that women ate when eating with women or with men did not differ. However, when eating with men, women indicated feeling that they overate and were rushed through their meal.