6 Crazy Sex Myths - Or Are They?

Takeaway: The more you know the better it feels.

Here’s a fact for you: Knowing more about sex is good for your sex life. But although sex is one of the most popular activities in the world (it originates back to, well, the beginning of mankind), it's also one of the most secretive. So, it’s only natural that countless myths have accumulated around the topic over the years. Some of them are outlandish and downright ridiculous (aphrodisiac green M&Ms, anyone?), but as crazy as they are, some myths are actually true.

Here are six of the most common beliefs about sex. Can you figure out which ones are true and which ones are false?

True or False: African men have bigger penises.

Are African men really better endowed than men of other races? Richard Lynn thinks he's found the answer. Lynn, a British professor emeritus of Psychology at the University of Ulster, collected data on penis size from 113 different countries and published the results in the scientific journal Personality and Individual Differences.

So what’s the verdict on this myth?

It appears to have some basis of truth, although critics of the study called the data flawed because it had been collected from websites. Lynn’s study concluded that African-American men are bigger than men of other races. Out of all 113 nationalities, the Republic of the Congo came out on top with an average penis size of 7.1 inches. In fact, the average penis size in the entire continent of Africa was 6.3 inches. The Ecuadorians, Ghanaians and Colombians, with average sizes of 7 inches, 6.8 inches, and 6.7 inches, respectively, weren't far behind. At the other end of the spectrum were India, (4 inches), Thailand (4 inches) and North and South Korea (3.8 inches). As for American men (which presumably includes men of African descent), they fell right around the middle of the group with an average length of 5.1 inches. (The list of things to know about the male member doesn't stop there. Find more fascinating facts in 10 Things You Didn't Know About Penises.)

True or False: The shape of a woman’s pout is linked to her ability to achieve vaginal orgasms.

Any man who believes that the clitoris is the only key to a woman’s sexual satisfaction is sorely mistaken. Vaginal orgasms - or at least orgasms achieved through vaginal intercourse - do exist. In fact, it’s been said that 30 percent of women are capable of achieving an orgasm through intercourse alone. What sets them apart from the rest? Could their face hold a clue?

Yes, it could. Just ask Stuart Brody, a psychology professor at the University of the West of Scotland. In 2011, he conducted a survey of 258 mainly Scottish women with a mean age of 27 years and concluded in the Journal of Sexual Medicine that having a prominent tubercle - the middle of the upper lip with two areas that may or may not point out - indicates that a woman is more likely to have vaginal orgasms. Brody’s co-author, Rui Miguel Costa, suspects that the link between a woman’s upper lip and her ability to orgasm via intercourse may have originated in utero. That's because the formation of a fetus’s tubercle could be connected to the formation of the neural circuits that affect vaginal orgasm. No wonder men find a woman's lips so intriguing! (If sex alone doesn't do it, you can always add a vibrator. Learn more about these handy gadgets in Vibrators: Bigger and Getting More Buzz Than Ever.)

True or False: Chocolate makes you horny.

Not only is chocolate delicious, it’s known to be an aphrodisiac. That isn't too far-fetched. Chocolate does contain two chemicals that trigger feelings of love and sexual arousal: tryptophan (a building block of a brain hormone that puts you in the mood) and phenylethylamine (a natural neuromodulator that stimulates positive feelings, often similar to the feeling of falling in love).

Sounds promising, right? Unfortunately, this one's false because the amounts of these chemicals in chocolate are too small to inspire any feelings of love or sexual arousal, even for those who eat chocolate every day. In 2006, an Italian physician named Andrea Salonia and several of her colleagues found no link between chocolate consumption and sexuality. The study was published in the Journal of Sexual Medicine, and it concluded that all the aphrodisiac qualities believed to be in chocolate are purely psychological.

True or False: You can't catch an STD if you have sex in water.

Although bathtub sex scenes are common in pornography and even mainstream movies, in reality, sex and water aren't the best combination. And when it comes to STDs, this one's flat-out false. Not only does water wash away the body’s natural fluids, it also weakens your skin. So, having sex in water actually increases your chances of catching an STD. That's because having sex in water can tear your unmentionables, making it easier for bacteria and STDs to enter your body. Wearing a condom helps, but not much because chlorine or heat can weaken the rubber, making it more likely to break. The best way to avoid such a scenario is to stick to land-based sexual activity - and save the underwater stuff for safer foreplay.

True or False: You can determine the size of a man's penis by looking at his fingers.

Men with big feet tend to have big … shoes. Really. There has been no evidence linking a man’s penis size to his foot size. However, there is a way to tell whether a fully-clothed man is packing a zucchini or a baby carrot. All you have to do is to look at his index and ring fingers. Are they about the same length? If so, you might have a Ron Jeremy in your hands!

Researchers at Gachon University Gil Hospital in South Korea found that the lower a man’s index-to-ring-finger ratio, the longer his penis is likely to be. The 2011 study, which was published in the Asian Journal of Andrology, suggests that the correlation between the index-to-ring-finger ratio and penis size may be a result of prenatal testosterone. More testosterone during fetal development has been shown to create a lower index-to-ring-finger ratio … and perhaps a bigger baby maker.

True or False: Sex can cure headaches

Forget aspirin. Find a sexual partner! Yes, this old wives tale is true. Sex can cure headaches, and there are several studies to prove it. In 1988, a neurology professor named James Couch discovered that 61 percent of women who tried sex with a migraine got some relief. He also found that sex could stop a migraine altogether. In a more detailed study conducted by South Illinois School of Medicine, 31 percent of the migraine sufferers reported relief after an orgasm while 15 percent more said their headaches were completely gone.

But there's a catch: In order for sex to actually cure your headache, you need to have an orgasm. So next time your partner says, "Not now; I’ve got a headache," consider it your personal mission to help them find relief.

The topic of sex is stuffed with myths and misconceptions. The more you know about your body and how it works, the more you'll be able to use it to your advantage. So next time you hear something about sex, ask yourself whether it's fact or fiction. Better yet, ask us!