A study published this month in the journal Evolutionary Psychology Science found that men change their eating habits significantly around women. The researchers, who observed male and female eating habits at an all-you-can-eat pizza place, found that men consumed 93 percent more pizza (1.44 more slices) and 86 percent more salad in the presence of women.
They believe that men may be overeating as a way to impress their female dining companions. “Our observation of men ‘eating heavily’ is sensibly viewed in an evolutionary perspective as men ‘showing off,’” the study explains.
“There is recent work that explores the possibility that eating spicy food might be a way that people ‘show off’ since it (arguably) signals a higher tolerance for something that others would consider painful,” Kevin Kniffin, the study's lead author, told The Atlantic. “The new research article examines the question of whether overeating might function as a comparable kind of signal that a person is healthy enough that they can engage in unhealthful behavior of excessive eating (and still end up okay).”
Women in the study, meanwhile, ate the same amount whether or not men were around—but that doesn’t mean their eating habits were completely unchanged. The study found that while they didn't actually eat more, women were more likely to feel that they’d overeaten when men were around. Ultimately, it seems like both men and women may feel self-conscious when eating around each other—but express that self-consciousness in very different ways.