When people talk about sex and prostate cancer, it's usually in the context of wondering what sex will be like after treatment. A relatively new area of research, though, is looking in to the possible connection between sexual activity and risk of prostate cancer.
Sex and Prostate Cancer: Is There a Connection?
The unsatisfying answer to this question is: yes, no and definitely maybe. Most research has approached this question in one of two ways: Some studies compare men who have been diagnosed with prostate cancer to men who haven't and asked them about their sexual activities throughout their life (masturbation, partner sex, number of partners, etc...) to look for significant differences.
Another approach is to ask men who don't have prostate cancer about their sex lives and then follow them for many years and note who ends up with the disease and who doesn't. The researchers can then go back and look for any differences in the sexual activities of the two groups. There are a dozen or so studies that have mostly taken the first approach and one very large U.S. study that took the second. To get an idea of why there is no satisfying answer to this question, consider some of the findings from these studies:
- A study of 1,000 Australian men who had been diagnosed before the age of 70 found no association between prostate cancer and the number of sexual partners. They also found that men who ejaculated more frequently in their 20s had a reduced risk of prostate cancer.
- A study comparing 430 British men, who had been diagnosed before the age of 60, found that increased masturbation during their 20s increased the disease risk, while increased masturbation in their 50s decreased the risk. Unexplained in this study is the fact that masturbation was associated with increased risk but intercourse was not.
- A study following almost 30,000 U.S. men for 8 years found no overall relationship between how often a man ejaculated and prostate cancer risk; however, they found that those men who reported the highest frequency of ejaculation did have somewhat reduced risk.
- Reviewing 19 previous studies, the authors of the above study point out that nine of the studies found that with increased sexual activity came an increased risk, seven found that with increased sexual activity the risk was decreased and three found no relationship at all.
Why so many conflicting results? One of the reasons is that few of these studies looked at the same thing the same way. Some defined sexual activity as intercourse, some defined it as any ejaculation, some didn't define it at all. And each study used a different way of asking how much sex at what age, which itself is emerging as an important factor.
So the "yes" is that most studies have found some kind of relationship. The "no" is because a few very good ones don't think the relationship is strong enough to be significant. Taken as a whole, though, I'd stick with the "definitely maybe" answer. Unfortunately, we're still years or more from understanding what exactly the maybe means.
Possible Connections Between Sex and Prostate CancerResearchers have several theories as to why having more or less sex (or ejaculations) could increase or reduce your risk of prostate cancer. Theories include:
Sexually transmitted diseases. One theory suggests that cellular changes from getting an STD may increase the risk of developing prostate cancer. Those men with more sexual partners tend to be at greater risk of STDs.
Reduced toxicity, increased immune function. When a man ejaculates, toxins are expelled from the body in to the semen. Some researchers who have found that increased ejaculations are associated with decreased prostate cancer suggest that it may be that more ejaculations reduce the amount of toxins and the length of time toxins stay in the body. They also point to research that more frequent ejaculations are linked to better immune functioning. In this theory, ejaculation is seen as a flushing out of toxins.
Hormones. While most researchers agree that there is a relationship between testosterone and male sexual function, there is no agreement on how this relationship works. There is also a belief that prostate cancer is hormone-dependent, although this, too, is hard to prove and explain. It’s possible, some researchers argue, that a sex hormone that impacts sexual activity may also impact risk of prostate cancer. Whether that’s a one way relationship (e.g. more testosterone = more sexual activity = greater risk of prostate cancer) or a more complicated one, though, remains to be seen.
Reduced Stress. Yet another theory (considered “highly speculative” by the researchers who proposed it) links increased ejaculation with decreased prostate cancer risk, suggesting that it’s the release of psychological tension during ejaculation that has a protective effect.
Early-Life Exposures. More recently some researchers have suggested that the reason for such inconclusive findings is that current research focuses on potential risk factors during the adult years. Instead researchers suggest that early experiences may have a more significant impact on a developing prostate. In the context of sex this mostly means age of first intercourse and number of sexual partners, although that data is understood to be likely related to STDs. Still a 2013 review of studies calls for including early sexual experiences apart from STDs in future research.
The Bottom LineSo should you masturbate more or less? Have more or less sex with a partner? And if you’re having sex with someone of the same sex, what should you do? It’s unfortunate that almost all the research has been with white, heterosexual men. This may not make a difference, but it would be good to know.
At this point, we don’t even know how the relationship between sexual activity and prostate cancer risk works -- let alone knowing that if you have sex (or ejaculations) X number of times a week, you’re doing something good for your body. Given the many health benefits of sex (and health benefits of orgasms), I would suggest it’s a bit premature to stop yourself from masturbation or partner sex at this point.
What all of the researchers in this field agree on, though, is that a healthy prostate is the result of a healthy lifestyle (including a proper diet, exercise, balancing stress and relaxation and seeing your healthcare provider). And what all sex educators agree on is that healthy sexual expression is a part of a healthy lifestyle.
Dimitropoulou, P., Lophatananon, A., Easton, D., et al. "Sexual Activity and Prostate Cancer Risk in Men Diagnosed at a Younger Age" BJU International Vol. 103 (2008): 178-185.
Giles, G.G., Severi, G., English, D.R., et. al. "Sexual Factors and Prostate Cancer" BJU International Vol. 92 (2003): 211-216.
Leitzmann, M.F., Platz, E.A., Stampfer, M.J., et al. "Ejaculation Frequency and Subsequent Risk of Prostate Cancer" JAMA Vol. 291, No. 13 (2004): 1578-1586.
Sutcliffe, S. and Colditz, G.A. "Prostate Cancer: Is It Time to Expand the Research Focus to Early-Life Exposures?" Nature Reviews Cancer Vol. 13 (2013): 208-218.