7 popular sex rumors proved true — or totally false

The truth about getting it on

The basic science behind the birds and bees may be universally known, but its details can sometimes go off the rails — especially with popular media, cultural norms, and old wives’ tales spinning their own versions of things that go bump in the night.

To clear things up, we turned to Justin Lehmiller, a Boston-based social psychologist, who currently teaches an undergrad course on human sexuality at Harvard University. Lehmiller is the author of popular sex blog, The Psychology of Human Sexuality, where he debunks and decodes popular sex myths, rumors, and questions on a regular basis.

We picked seven popular assumptions and misconceptions about sex and asked the doctor for his diagnosis.

What did we learn? Well — that we were mostly wrong. But that’s just the beginning.

Lehmiller also chatted with Boston.com readers on Nov. 18. Check out the transcript here.

Men think about sex every 7 seconds

Every seven seconds may seem extreme but it’s a common factoid that gets thrown around — but is it true?

Not so fast — or so often.

This is false.

“If you look at the research, men are actually thinking about sex twice per hour. It’s nowhere near the every seven second theory,’’ said Lehmiller. “And the other half of that is that people think women never think about sex. But if you look at the research women are thinking about sex at least once an hour. Men are certainly thinking about it more than women but women are thinking about sex a lot more than people assume.’’

Aphrodisiacs work. Pheromones are real.

Aphrodisiacs and pheromones are two dramatically different things, but their desired end results are relatively similar. Aphrodisiacs are alleged sex drive stimulants and commonly refer to foods and herbs. Meanwhile, pheromones are chemical blends meant to stimulate an action or behavior in another member of the same specifics, romantic and/or sexual reactions taking center stage in this case.

Pheromones have more legitimate scientific backing (honey bees use them to chit-chat/backstab) but that doesn’t keep oysters and dark chocolate from popping up on every Valentine’s Day menu around town.

“There’s a fair amount of research suggesting that we pick up on other people’s chemical scents and that may play a role in our attraction,’’ confirmed Lehmiller. “For example, they’ve conducted blind, placebo-control studies where people wore pheromones and some wore a placebo solution and the people who wore the pheromones report having a lot more sex than the people wearing the placebos.’’

“When it comes to aphrodisiacs, there are so many of them that people assume will increase their libido — oysters, figs, or chocolate, all of these kinds of things — but the reality is, they don’t really live up their promises. They may work but it probably has to do with people believing that it will affect their behavior. The effect of aphrodisiacs relies on suggestion more than anything.’’

So there’s some truth to arrousal-and-attraction-inducing pheromones in humans but as for aphrodisiacs? False.

“It’s highly unlikely it’s going to bring the desired effect unless you and your partner believe it’s going to have that effect.’’

You can tell the size of a man’s penis by his …

We’ve heard the rumors. But is it true?

“I’ve looked into the research on this and there really isn’t anything supporting the idea that you can tell the size of a man’s penis by the size of his hands, feet, or nose,’’ said Lehmiller. “There is a relationship between a man’s height and penis size. Taller men tend to be more well endowed on average but not always. There are no absolutes when it comes to this but on average there’s an association with height.’’

But as for telling by the size of a man’s hands/feet/nose? That’s absolutely false.

Women can have multiple orgasms

Too good to be true?

Nope. This one is true.

“That is absolutely true, but a lot of people seem to be under the impression that it’s not,’’ said Lehmiller. “The research that I’ve seen suggests that most women are capable of experiencing multiple orgasms but they might not know or realize it. The research has shown that a significant number of women have reported this exerpience but it seems to be very low among men. Men experience a refractory period after orgasm that makes a second orgasm very unlikely to happen.’’

Sorry guys.

Women reach their sexual peak in their 30s, men in their early 20s

Could this possibly be true? Do different sexes “peak’’ sexually at different ages. Possibly.

But probably not.

“This commonly gets thrown around in popular media portrayals, like Stifler’s mom hooking up with high school and college students,’’ said Lehmiller. “They’re supposedly the right match because they’re at their peak and she’s at her peak, but if you look at the research, there does seem to be some peaks that go along with our age but they’re really not as big as the popular media makes them out to be.’’

So this is false. Sort of.

“There’s some research that shows that women have more thoughts and fantasies about sex in their 30s but it’s not doubling or dramatically increasing. There’s a slight increase,’’ continued Lehmiller. “And the same is true with younger men. They tend to have more thoughts and fantasies about sex than older men but it’s really not like the huge difference that everyone seems to assume.’’

Masturbation can be bad for a man’s health

Come on, guys. Really?

Well, according to Lehmiller, this question comes up a lot. And the concerns vary across the board.

“From blindness to hairy palms to just using up all of your sperm, there are all kinds of things people are worried about,’’ said Lehmiller. “But these are just myths that have been passed down from generation to discourage people from pleasing themselves. The reality is that there are no negative health effects to masturbation and in fact, the research has shown that people who orgasm more frequently tend to have better health, if anything. People who orgasm more tend to live longer.’’

Say what?

“There’s this one really interesting study where they had men come into a lab and they masturbated to orgasm or not. They then took a blood sample and looked at their immune system functions and they found that the men who had recently orgasmed had much higher immune functioning than the men who hadn’t. It suggests that there may be some health protective effects of this.’’

So is masturbation bad for your health? Nope. Quite the contrary. This is false.

Gay men get more action than straight men

Do gay men get it on more frequently than straight men?

Not really.

“It’s true that, on average, gay men report having had more sexual partners than straight men. However, gay men’s average is thrown off by a small subset of guys who have extremely large numbers of sexual partners,’’ said Lehmiller. “If you look at the median or 50th percentile instead of the average, you’ll see that gay and straight men are actually pretty similar.’’

“Also, studies have found that gay and straight men report equally high sex drives, which tells us that gay men aren’t hardwired to be any more promiscuous.’’

Hear that, folks? Equal opportunity friskiness. This one is false.