Researchers from Cornell University found men who dined with at least one woman at an all you can eat Italian buffet ate a whopping 92% more pizza and 86% more salad than men who dined with other men.
Women, on the other hand, did not eat significantly different amounts of food when eating with men verses women, but they did more often report feeling more full or as if they were rushed through their meal when they ate with men, according to the study published online Nov. 10 in Evolutionary Psychological Science.
The researchers measured how much 105 adults ate at lunch by unobtrusively observing them over two weeks and then intercepting them at the cash register to ask them about their level of fullness, feelings of hurriedness and comfort while eating.
They found men eating with men at about 1.55 pieces of pizza and 2.69 bowls of salad compared to men who ate 2.99 pieces of pizza and 5 bowls of salad when they accompanied women.
The research suggests eating heavily is a way men “show off.” The over-consumption could signal to potential “mates” that they are strong, energetic and healthy, even though the long-term consequences of the behavior would result in the opposite outcome, according to the study.
The concept of men eating more to show off to women could be similar to how some women under eat around men to appear more attractive in a culture that values thinness, the researchers added.
They also hypothesize the over-eating could be a signal of dominance to other men.
Finally, the researchers rule out the possibility that men ate more around women because they were nervous. Rather, they found that all diners had similar comfort levels regardless of the sex of their eating companions.
The findings could have implications for food and beverage marketing if the connection between dining with women and eating more extends to advertising with women influencing men to eat – and therefore buy – more.
The researchers do not address this possibility directly, but they note that eating contests – which tend to be male dominated – often “feature scantily clad women as part of the event,” which they say suggests the presence of women could increase consumption.
A limitation of the field study was, as the researchers noted, that they were not able to “ask a battery of psychological questions,” that might reveal the motivations for eating heavily around women or the extent of women’s influence on men’s eating – even when not physically present as would be the case in marketing.