If you didn’t know that sex is good for your health, you haven’t been paying attention. Depending on which headline you believe, sex has six or eight or 10 or 16 or 17 different health benefits. According to the scientific research touted in stories like these, sex can burn calories, cut stress, ease depression, relieve pain, reduce the risk of cancer and heart attacks, lessen your risk of dying, and even reduce the frequency of hot flashes in menopausal women.
Assuming that these studies are correct (more on that in a minute), and that sex is good for your health, then the obvious next question would be, how should you arrange your sex life so as to maximize the health benefits? Is a series of one-night stands as salubrious as a long-term coupling? Could a few bouts of masturbation be as nourishing and wholesome as a single night of conventional intercourse? Stuart Brody, a psychologist at the University of the West of Scotland, has made a career of studying such matters, and his 2010 review paper, "The Relative Health Benefits of Different Sexual Activities," concluded that penile-vaginal intercourse (PVI) gives the greatest physiological boost. He backs up this assertion with data from a 2009 survey of nearly 3,000 Swedes, in which people who reported the highest frequencies of PVI also reported high levels of sexual satisfaction, health, and well-being.
Not that masturbation is so bad. A 1988 study found that genital self-stimulation increases pain thresholds and produces an analgesic effect in women, and a 2003 study linked masturbation to a reduction in prostate-cancer risk, which the researchers attributed to ejaculation frequency. But a subsequent study failed to confirm the relationship and, no doubt to the chagrin of many men, concluded that prostate cancer risk was unrelated to a man’s ejaculation count. (Some studies suggest a link between sex and breast cancer, too: One found a reduced risk of breast cancer among women who’d had multiple sexual partners, though another found that women who’d had children fathered by different partners did not have a lessened risk of the disease.)
If you’re tempted to go it alone, know this. Masturbating might get you off, but it probably won’t help you out of a funk. Brody’s Swedish study found that people who reported frequent masturbation scored lower on measures of health and well-being than those who engaged in frequent PVI. A 2004 study of middle-aged women found that those who suffered from depression masturbated more and reported less satisfaction in their partnered sexual experiences than women without depression.
The sexual cure for depression, apparently, involves semen. A survey of just under 300 female college students in Albany, N.Y. found that depression (as measured on a depression scale) increased the longer it had been since a woman had experienced PVI. The happiest women in the study were those who had the most PVI, but this antidepressant effect evaporated if they’d used condoms. Students who hadn’t engaged in PVI, or said they used condoms, reported more suicide attempts than those who said they never used condoms during sex. While the study isn’t rigorous enough to provide any solid conclusions, it’s theoretically possible that semen really does have antidepressant properties, since it’s loaded with hormones, neurotransmitters and other chemicals, including testosterone, prostaglandins, and hormones that stimulate ovulation.
OK, so let's say you have a partner. What's the best—and by best I mean healthiest, of course—sexual position? Research shows that if you’re getting busy to burn calories, the missionary position would be your best bet. But don’t skip your workout just yet: A 2008 study found that the physical demands of sexual activity are both moderate and short-lived.
Sex with a spouse may be healthier for men than sex with an illicit lover, especially if they’re doing the latter in a secret place. A paper published in September found that the majority of penile fractures seen in one Maryland hospital happened during extramarital sex in “out-of-the-ordinary” locations like cars, elevators, and public restrooms.