A new study debunks that myth, finding that men think about sex 19 times a day, on average. That's still more than women, who report about 10 sexual thoughts a day.
The study involved 163 female and 120 male college students aged 18 to 25. Lead researcher Terri Fisher, of Ohio State University, had them use click-counters to tally how many times they thought about one of three biological functions: sex, eating or sleeping.
Sexual thoughts were defined as "sexual activity of any kind, fantasies and erotic images, sexual memories and any arousing stimuli."
The study also found that men like eating and sleeping almost as much as sex: they have thoughts about food 18 times a day, and sleep almost 11 times a day.
For women, it's nearly 15 food thoughts and 8.5 sleep thoughts.
Based on questionnaires the participants filled out at the beginning of the study, their estimates of how often they thought about eating, sleeping and sex were all much lower than the actual number of thoughts they recorded.