20 Myths About Sex You Still Believe

By Charlotte Hilton Andersen, Reader’s Digest

What you didn’t learn in high school sex ed: the surprising, science-backed proof about aphrodisiac foods, men’s and women’s desire, and more.

Myth: Sex burns major calories

Truth: Experts estimate thirty minutes of sex burns 85 to 150 calories. Theoretically, you need to burn about 3,500 calories to lose a pound of body weight, so if you were using up 100 calories every time you had sex, you could lose one pound if you had sex 35 times. The problem is this: Most people are not having sex for thirty minutes. Instead, the average duration of sex is closer to five minutes. In fact, the biggest increase in your heart rate and blood pressure during sex only occurs for about fifteen seconds during orgasm, and then things quickly return back to normal. Sex may not burn a lot of calories, but having sex once a week can actually help you live longer.

Myth: There’s a 10-year difference between women’s and men’s sexual peaks

Truth: Men’s testosterone peaks at around age 18, but women’s estrogen levels peak in their mid-20s. Since low hormone levels have been associated with lower sexual drive, some have asserted that when your levels are at their highest, your drive must be at its peak. But if we believe frequency of sex to be the factor that matters most in sexual peak, then there’s no difference between men and women. Sexual desire constantly fluctuates, and is related to many more factors than age. Over the course of a lifetime, you will see your sexual desire and activity go up and down many, many times.

Myth: Sex can give you a heart attack

Truth: Having sex more often is connected to having a healthier heart. In one study, men who reported having sex twice a week or more had a lower risk of developing cardiovascular disease. The chance of having a heart attack while you are having sex is also very low. The Framingham Heart Study tells us that for men who do not have diabetes or smoke, the chance of having a heart attack during sex is one in a million! What if your heart has already had problems? The truth is that most people just do not exert themselves that much during sex! The physical exertion most people put in when having sex is similar to walking up two flights of stairs. Here are some things sex therapists wish you knew.

Myth: Don’t leave socks on when getting intimate

Truth: A sex study in the Netherlands did brain scans on men and women while their partners attempted to give them orgasms. Apparently, it was drafty in the scanning room, and a lot of study participants were complaining about having literal cold feet. When the participants were given socks to keep their feet warm, significantly more were able to have orgasms.

Myth: Oysters and chocolate are turn-ons

Truth: No study has ever shown any sexually enhancing effect from oysters. They do contain a lot of zinc, which sperm need to be healthy, but otherwise, scientists have found no special ingredient to suggest it has any sexually enhancing effects. Several studies suggest that chocolate is tied to lower blood pressure and better functioning of blood vessels, which might keep the penis working well for erections. Chocolate can also stimulate a small release of mood-boosting phenylethylamine and serotonin into our systems, and people who are in better moods may want to have more sex! That said, if a food makes a person thinks about sex—whether because it resembles intimate anatomy, as oysters might, or even because the person believes it might be an aphrodisiac—then that food might become an aphrodisiac. Here are 31 natural libido boosters for better sex.

Myth: Men think about sex every seven seconds

Truth: A recent study from Ohio State University published in the Journal of Sex Research effectively debunks this myth. Looking to tally up the true number of times men (and women!) actually thought about sex in a day, the university had 238 students keep track of their thoughts about food, sex, or sleep for one whole week. The results? Men think about sex far less than you think, averaging about 19 sex thoughts per day instead of the nearly 8,000 thoughts per day that would be netted if men were really thinking about sex every seven seconds. Thoughts about food came in at a close second, with 18 thoughts per day, while sleep amounted to 11 thoughts per day. As for the women? They averaged about 10 thoughts about sex, 15 thoughts about food, and 8.5 thoughts about sleeping per day.

Myth: All women experience orgasm through intercourse

Truth: Studies report that nearly 75 percent of women aren’t able to orgasm through intercourse alone, according to ABC News. And, according to another recent study published in the Journal of Sex and Marital Therapy, nearly 37 percent of women said they need some other sort of stimulation during intercourse to achieve orgasm. Be sure to check out these ways to improve your sex life in just one day.

Myth: Sex can affect sports performance

Truth: This theory has been debated for many years, with coaches often telling their athletes to abstain from sex before big games or competitions. According to CNN, the idea comes from Ancient Greece and traditional Chinese medicine, with the prevailing thought being that not having sex would help “increase frustration and aggression, and boost energy.” However, recent research suggests sex has little impact on athletic performance—and could actually have a positive effect instead. Next, don’t miss these 48 simple ways to improve your sex life.

Myth: Having sex can cause a pregnant woman to go into labor

This myth is so pervasive that even doctors will tell their full-term patients to give it a try. But not only does having sex near your due date not start labor, it may actually delay it, according to a study done by the Ohio State University Medical Center. Researchers found that women who were sexually active in the final three weeks of their pregnancies carried their babies an average of 39.9 weeks, compared to 39.3 weeks for women who weren’t having any sex. It’s not a huge difference but when you’ve got a seven-pound bowling ball pressing against your lungs, every day counts! However, a regular orgasm can help you slow down aging.

Myth: Women take longer to get turned on than men

“Women heat up like Crockpots while men are like microwaves” is a popular way to explain the supposed difference in how the genders respond to foreplay. The truth? It turns out that there is absolutely no difference in the time it takes men and women to reach peak arousal, according to a study done by McGill University. The researchers used thermal imaging rather than relying on self-reporting, which may mean that if you think it takes you a lot longer to get turned on than it does your husband, the cause may be more mental than physical. Trouble getting turned on? Wait for nighttime; science says the best time to have sex is right before bed.

Myth: Birth control is a mood-killer

Is the thing that’s preventing pregnancy also preventing you from getting any in the bedroom? Hormones influence our sex drive and birth control pills alter a woman’s hormone levels, so it makes sense that being on the pill might have an effect on her sex drive. But this popular belief is flat wrong: Taking the pill has no influence on a woman’s drive, according to a study published in The Journal of Sexual Medicine. Another popular birth control myth is that condoms make sex less pleasurable; a separate study done by Indiana University found that both men and women reported more sexual pleasure when using contraception (likely because they were less worried about the consequences).

Myth: Blackouts, storms, and terrorist attacks cause a baby boom nine months later

Thanks to a blackout, a blizzard, a bomb scare, or some other factor that lands you stuck at home with no lights and no internet, you decide you’ve got to entertain yourselves by getting busy in the bedroom, right? (And hey, you’re just trying to stay warm!) While this sounds like a fun plot to a rom-com, this one is an urban legend, says S. Philip Morgan, a Duke professor of sociology and demography and author of a study looking at the effects of these events on birth rates. The data simply doesn’t support the idea of a “blackout baby boom,” he says.

Myth: Sexting is just for horny college kids

Much has been said about the dangers of sexting—and those are very real, especially in casual relationships. But when done in a committed, secure relationship, it can take your sex life from rote to raging. Sending sexual messages and pictures to your significant other increases not only your sexual satisfaction but also your overall happiness in your relationship, says Emily Stasko, MS, MPH, lead author of a study on the impacts of sexting on relationships. (Note: Sex and sleep are the only two things guaranteed to make you happy, according to science). The committed relationship part is key, however, as people who identified in the study as single found that sexting had the opposite effect, reducing sexual satisfaction.

Myth: Sex and intercourse are one and the same

Intercourse simply means there is penetration; having sex can, and should, include so much more than that, says Melissa Coats, a licensed professional counselor and sex therapist. Sex has an emotional component and encompasses a wide variety of sexual activities, which may or may not include intercourse, she explains. Conflating the two can cause a lot of trouble for couples dealing with things like pain during intercourse, erectile dysfunction, or past traumas. “It’s a myth that every time you have sex, it must include intercourse or it somehow doesn’t count,” she says. Do you have any of the 10 silent signs you have intimacy issues?

Myth: You can tell who has an STD

“A very common sex myth people believe is that you’ll be able to tell if someone has an STD by looking at them,” says Robert Huizenga, MD, author of Sex, Lies & STDs. The truth is that many sexually transmitted infections don’t show outward symptoms or may not show up until much later. There’s no substitute for getting a medical screening and being totally honest about the results with your partner—and expecting the same transparency from them, she says. This is just one of the things you need to know about having sex in your 40’s.

Myth: Having a much younger lover means mind-blowing sex

Has Hollywood sold you on the desirability of being a “sugar daddy” or “cougar”? Don’t believe it. Having a May-December relationship isn’t ideal and, in fact, is detrimental to both partners, says a study published in the Review of Economics and Statistics. They found that those married to much younger or older spouses have lower earnings, lower cognitive abilities, are less educated, and—to completely annihilate the stereotype—are less physically attractive, than couples of similar ages. Oh, and the sex is worse too.

Myth: There’s no such thing as too much masturbation

Delayed ejaculation—meaning when men struggle to have orgasms in conventional ways due to a reliance on porn and masturbation—is way more common than you think, says Cyndi Darnell, an Australian clinical sexologist and sex and relationship therapist. Both men and women can become so accustomed to a certain kind of pressure and speed from stimulating themselves that they find it difficult or even impossible to orgasm with a real-life partner, she explains. A reliance on porn can also give you unrealistic expectations of how your partner should look and act, another mood killer in the bedroom.

Myth: Breakup sex is a terrible idea

Not only does hooking up with your ex not make your breakup more complicated, it could even help you move on, finds a study, published in The Archives of Sexual Behavior. “This suggests that societal hand-wringing regarding… sex with an ex may not be warranted,” the researchers concluded. “The fact that sex with an ex is found to be most eagerly pursued by those having difficulty moving on, suggests that we should… evaluate people’s motivations behind pursuing sex with an ex.” Just make sure you’re avoiding the 15 things you should never do after a breakup.

Myth: Sex toys are “cheating”

“I’ve heard a lot of myths about sex toys, such as they can ‘break’ you or ruin you for ‘real’ sex,” says Stella Harris, certified intimacy educator and sex coach and author of Tongue Tied: Untangling Communication in Sex, Kink, and Relationships. “It’s not cheating if you bring toys or masturbation into your partnered sex! Everyone needs a helping hand sometimes, even if it’s their own. Don’t hesitate to touch yourself during sex, or encourage your partner to do so.” As long as they are used in moderation they won’t reduce your genital sensitivity or do other physical damage. You do need to be careful, however, to pick only sex toys that are safe and non-toxic. Silicone, steel, Pyrex, glass, or specially laminated wood are the only materials certified as safe for use inside your body, according to a Yale review. Next: Read up on the 14 sex problems you should take seriously.

Myth: A woman’s vagina can reveal how many partners she’s had

Vaginas can temporarily stretch to accommodate a large object—how else would women ever survive childbirth?—but they don’t stay stretched out, Harris says. This goes against the “wisdom” currently being spread all over the internet that having multiple partners, a partner with a large penis, or using large sex toys can make a woman’s vagina loose. How tight or loose a vagina feels depends on the woman’s genetics and the fit between her and her partner.