The old cliche is true - men DO think about sex more often than women - and researchers have proved it by sending students out into the world to 'log' what they are thinking about.
But the findings were a surprise. Men also think about sleeping, eating and other basic biological functions more than women - and any men who have spent the previous few decades worrying that they may not be 'manly' enough as they don't 'think about sex every seven seconds' can rest easy.
The average man thinks about sex 20 times a day or less, say researchers from Ohio State University. The people who think about sex most of all tend to be... people who are comfortable with the idea of sexuality itself.
The idea that men 'think about sex every seven seconds' is commonly bandied around - but new research, where students actuallly logged what they were thinking about during the day, debunks the idea
'For a man to think about sex every six seconds, he would have to have 8,000 sexual thoughts a day - young men think about food almost as much as they think about sex'
The study actually sent students into the field to record what they were thinking about - and the researchers found that men focused on biological needs, such as eating and sleep more frequently than women do.
And the research discredits the persistent stereotype that men think about sex every seven seconds, which would amount to more than 8,000 thoughts about sex in 16 waking hours.
In the study, the median number of young men's thought about sex stood at almost 19 times per day.
Young women in the study reported a median of nearly 10 thoughts about sex per day.
As a group, the men also thought about food almost 18 times per day and sleep almost 11 times per day, compared to women's median number of thoughts about eating and sleep, at nearly 15 times and about 8 1/2 times, respectively.
The college-student participants carried a golf tally counter to track their thoughts about either eating, sleep or sex every day for a week. Each student was assigned to just one type of thought to record. Before receiving the tally counter, they had completed a number of questionnaires and were asked to estimate how often they had daily thoughts about eating, sleeping and sex.
Overall, a participant's comfort with sexuality was the best predictor for which person would have the most frequent daily thoughts about sex.
A ham sandwich: While young men at their sexual peak DO think about sex 19 times a day, they also think about food 18 times
'Frequency of thinking about sex is related to variables beyond one's biological sex.'
Correcting this stereotype about men's sexual thoughts is important, Fisher noted.
'It's amazing the way people will spout off these fake statistics that men think about sex nearly constantly and so much more often than women do,' she said.
'When a man hears a statement like that, he might think there's something wrong with him because he's not spending that much time thinking about sexuality, and when women hear about this, if they spend significant time thinking about sex they might think there's something wrong with them.'
The study appears online and is scheduled for publication in the January issue of the Journal of Sex Research.
The study involved 163 female and 120 male college students between the ages of 18 and 25 who were enrolled in a psychology research participation program.
Of those, 59 were randomly assigned to track thoughts about food, 61 about sleep and 163 about sex. Most students were white and self-identified as heterosexual.
The college-student sample made it comparable to previous research and involved an age group at which gender differences in sexuality are likely at their peak.
Before heading out into the 'wild' to record their thoughts, the students completed questionnaires about how much time they devoted to thinking about food, sex, and sleep
'There's really no good reason that our society should have believed that men are thinking so much more about sex than women'
These included a sexual opinion survey to measure a positive or negative emotional orientation toward sexuality; a sociosexual orientation inventory measuring attitudes about sex and tracking sexual behavior and levels of desire; a social desirability scale to measure respondents' tendency to try to appear socially acceptable; and an eating habits questionnaire and sleepiness scale.
They also were asked to estimate how many times in an average day that they thought about sleeping, eating and sex.
Researchers then gave each student a tally counter device and told those assigned to the sexual thoughts condition to click the device to maintain a count their of thoughts about sex.
They were told to count a thought about any aspect of sex: sexual activity of any kind, fantasies and erotic images, sexual memories and any arousing stimuli.
Others were instructed to use the device to record thoughts about eating that included food, hunger, cravings, snacking or cooking, and thoughts about sleep that included dreaming, sleeping, napping, going to bed or needing rest.
The questions about food and sleep were designed to mask the true intent of the study's focus on thoughts about sex, Fisher said. However, the results about these additional thoughts provided important information about differences in thinking among males and females.
'Since we looked at those other types of need-related thoughts, we found that it appears that there's not just a sex difference with regard to thoughts about sex, but also with regard to thoughts about sleep and food,' she said. 'That's very significant. This suggests males might be having more of these thoughts than women are or they have an easier time identifying the thoughts. It's difficult to know, but what is clear is it's not uniquely sex that they're spending more time thinking about, but other issues related to their biological needs, as well.'
In raw numbers, male participants recorded between one and 388 daily thoughts about sex, compared to the range of female thoughts about sex of between one and 140 times per day.
'For women, that's a broader range than many people would have expected. And there were no women who reported zero thoughts per day. So women are also thinking about sexuality,' Fisher said.
'People who always give socially desirable responses to questions are perhaps holding back and trying to manage the impression they make on others,' Fisher explained. 'In this case, we're seeing that women who are more concerned with the impression they're making tend to report fewer sexual thoughts, and that's because thinking about sexuality is not consistent with typical expectations for women.'
The participants' estimates about how often they thought each day about eating, sleeping and sex were all much lower than the actual number of thoughts they recorded. This suggested to Fisher that previous research in this area – especially on thoughts about sex – was weak because almost all previous studies were based on participants' retrospective estimates about how often they thought about sex.
'There's really no good reason that our society should have believed that men are thinking so much more about sex than women. Even the research that had been done previously doesn't support the stereotype that men are thinking about sex every seven seconds,' she said.