September 23, 2017
Can Frequent Sex Prevent Prostate Cancer?
Claim Check

Can Frequent Sex Prevent Prostate Cancer?

by Gina Shaw  |  

The claim: Sex can protect against prostate cancer.

The facts: This one probably has some truth to it. Studies have found that frequent ejaculation (either from sex or masturbation) could have a protective effect against developing prostate cancer.

In one large study, which involved nearly 30,000 men in the Health Professionals Follow-Up Study, Harvard researchers assessed men’s ejaculation frequency at three periods in their lifetimes: ages 20 to 29, ages 40 to 49, and during the year prior to the study (1991). They then followed up with the men every two years to see if they developed prostate cancer. Those men who said they ejaculated more than 21 times per month, on average, across their lifetime had two-thirds the risk of prostate cancer as men who ejaculated just 4 to 7 times per month.

This study, published in the Journal of the American Medical Association in 2004, was particularly strong not just because of its size, but also because the researchers were able to rule out numerous factors that could confound the results.

In December 2016, a follow-up study, which tracked the same men for 10 additional years, confirmed that the most frequent ejaculators had a lower risk of developing prostate cancer than those who ejaculated less frequently. And even in men who ejaculated a more moderate amount, there was still some risk reduction. Those who reported 8 to 12 ejaculations per month in their 40s, for example, had a 10 percent reduction in prostate cancer risk, and those who reported 13 to 20 ejaculations per month in their forties had a 20 percent reduction. That’s what doctors call a “dose-response” relationship. It should be noted that the association applied to lower-risk prostate cancer (i.e., early-stage tumors that hadn’t spread beyond the prostate); the same relationship wasn’t observed for advanced prostate cancer.

The study’s authors concluded that “more frequent ejaculation . . . could represent an important means of reducing the profound medical costs and physical and psychological side effects of unnecessary diagnosis and treatment of low-risk tumors.”

Why would frequent ejaculation reduce the risk of prostate cancer? That’s still an open question. One theory is that ejaculation may help purge the prostate of carcinogens. But since observational studies such as these can only show association, not causation, it’s certainly possible that there’s another factor common among men who ejaculate frequently that accounts for their reduced risk. In any case, the evidence isn’t strong enough to recommend upping your sex or masturbation frequency for the sole purpose of preventing prostate cancer. But if you have frequent sex, masturbate a lot, or both, a healthier prostate could offer a welcome fringe benefit.

Also see Prostate Cancer: Tip to Reduce Your Risk.