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Everything you think you know about sex is a lie! Or many things, anyway. Here are five facts you’ve probably had backwards about getting it on, all according to a new book written by a pair of doctors, Don’t Put That in There! And 69 Other Sex Myths Debunked.

Monogamy may be rougher on women than it is on men. According to conventional wisdom, women are more likely to want a monogamous relationship because we’re more interested than men in establishing an emotional connection. Men, on the other hand, simply want sex, sex, and more sex, which, the theory goes, explains why dudes just aren’t built for monogamy, babe.

Research has shown that women’s libidos tend to nose-dive when they’re in a long-term relationship, but the same isn’t true for men. However, we might have been misinterpreting the meaning of this finding, suggest the authors, Dr. Aaron E. Carroll and Dr. Rachel C. Vreeman, both of the Indiana University School of Medicine. “While some would say that this means the women have an easier time being monogamous because their sex drive has gone down, sex experts would say that this is not the healthy state for these women,” they write. “The women are losing their desire to initiate sex or to have sex with their partners, which does not reflect sexual health.”

Men don’t hit their “sexual peak” early and women don’t hit theirs late. We repeat it so much we take its accuracy for granted: Guys reach their sexual peak during their late teens or early 20s, but women don’t reach theirs until later in life, when they’re in their 30s or 40s. To investigate the truthiness of this, Carroll and Vreeman looked into studies reporting the frequency of sexual activity among men and women at various ages. Research has uncovered huge disparities depending on the type of sex act, whether the individual was single or in a relationship, or even based on the way the question was asked. It’s not so easy to identify a clear “peak” for either men or women.

“Sexual desire constantly fluctuates, and is related to many, many more factors than age,” the authors write. “It’s likely that over the course of a lifetime, you will see your sexual desire and activity go up and down many, many times.”

Women have wet dreams, too. This is another one of those things about sex that we think applies exclusively to guys, but it’s simply not true. Although studies do suggest that more than 80 percent of men have a dream resulting in orgasm in their lives, the trouble is that most of the studies on this subject have only looked at men.

But Carroll and Vreeman cite a study conducted in the 1950s by Alfred Kinsey in which almost 40 percent of the women interviewed by the legendary sex researcher reported having a wet dream. Similarly, 37 percent of the 245 women surveyed for a study in the 1980s reported having a wet dream at some point in their lives, with 30 percent having had one in the last year. And these numbers may exaggerate the gender differences – it could be that women are too embarrassed to own up to having wet dreams since it’s culturally seen as something that only happens to men. But one thing is clear: This is not a dudes-only phenomenon.

It’s totally cool to leave your socks on during sex. Okay, nothing sounds less sexy than that, but hear Carroll and Vreeman out. They cite a study by Dutch scientists that found both men and women were more likely to have orgasms … when they were given socks. Eighty percent of the participants with socks on were able to have orgasms, but for the unfortunate sockless participants their ability to come was reduced to a coin-flip.

In this particular study, the researchers did brain scans on men and women while their partners attempted to get them to orgasm by stimulating their genitals. So, yes, okay, we’re talking about a laboratory setting, not an actual bedroom. But the real point here is that comfort and relaxation is key, and that may be especially true for women. “While genital stimulation was most important for men, women essentially needed their conscious brains to be able to shut off to have a real orgasm,” the authors write, arguing that it’s hard to relax if your feet are cold. So knock your socks off, or don’t! What’s important is that you’re comfortable.

Aphrodisiacs work, but not for the reason you think. People get a little winky-winky when referring to foods like oysters and chocolate and their supposed power to increase sexual desire, and most of us probably assume that there’s at least a little truth behind the idea of aphrodisiacs. Surely there must be some compound in the chocolate, some mysterious sexual stuff of the sea in the oysters? Not so, say Carroll and Vreeman. The amorous mythology surrounding these foods goes back thousands of years, but, scientifically speaking, no studies have ever found a specific link between oysters or chocolate and increased sexual desire.

But you know what they say is the biggest, most powerful sexual organ? Don’t be gross – it’s your brain. The mind is the most important part of the sexual experience, which may explain why the idea of aphrodisiacs has stuck around. “If you believe that a food will put you or your partner in the mood, then you will be in the mood,” they write. “It works because you believe it will.” If the placebo effect can work for pain relief and depression, why not sexytimes, too?