Don't believe that “masturbation harms the body” or that you must “quit lust” (戒色) to get better; what to watch is whether it is costing you sleep, work and relationships

Cost

Free. What you save is the money for “kidney-tonic” (补肾) folk remedies and “quit lust” (戒色) courses, and the anxiety of long-term self-blame.

What you get

First, the body. A U.S. study followed 31925 men up to 2010. Each person reported how many times a month they ejaculated, and they were grouped by frequency. Compared with men at 4 to 7 times a month, men at 21 or more times a month had prostate cancer HR 0.81 (95% CI 0.72–0.92, about 19% lower), calculated from frequency at ages 20 to 29. Calculated from frequency at ages 40 to 49, HR 0.78 (0.69–0.89, about 22% lower). The cancers that were reduced were mainly low-risk prostate cancers. On the other side, a British case-control study compared 431 patients diagnosed before age 60 with 409 controls. Those who masturbated often in their twenties and thirties had higher risk, and those who did so often in their fifties had lower risk. Next, porn. One systematic review and meta-analysis concluded that many people who feel “addicted” are more often experiencing a mismatch between their behavior and what they believe, not just watching a lot. A small number of people do feel unwell after each ejaculation, but this is not “harm to the body”; it is a rare illness called post-orgasmic illness syndrome (POIS). It calls for seeing a doctor, not for quitting lust. Of 45 patients in the Netherlands, 87% had onset within 30 minutes after ejaculation, 80% felt exhausted and weak, and 78% felt as if they had a cold. In 37 patients at a French hospital, recovery took an average of 4.7 days. The cause is not clear. In the Dutch study, 29 of the 33 who had a skin test (88%) were allergic to their own semen. A study of 24 patients in China, though, could not find allergy antibodies against semen, and the patients' anxiety and depression scores were high. A 2025 review found only 14 treatment studies, 12 of them single case reports. Of 211 sexual medicine experts worldwide, only 18% said more than 30% of patients got better (U.S. / UK / Netherlands / France / China)

Notes

Dispute. Both prostate cancer studies only recorded and had no comparison groups, and the frequencies were recalled by the men themselves, so the conclusion can only go as far as “no evidence of harm to the body was seen,” and cannot be turned around to urge people to do it more. The authors of the British study themselves say the part about the fifties may be that people got ill first and so did it less. The abstract of the porn review does not give an effect size, so only the direction is written here. The benefit is rated small because what is lowered is mainly low-risk prostate cancer, not death. The studies of post-ejaculation discomfort each have only a few dozen patients, and the literature says this illness is rare, but nobody has counted how many people in the general population get it. If almost every ejaculation leaves you drained, as if you have a cold, for several days, see a urologist or men's health clinic (男科) and bring up the name of the condition yourself. The signs that really call for psychiatry or psychology are: staying up late over it, missing work, hurting the relationship with a partner, and wanting to stop but being unable to. For staying up late, see §3.9 (don't stay up late for games, short videos or porn). If you worry that watching porn has caused erection problems, first go by §1.28 (if erection problems appear, get your heart and blood vessels checked first). For the legal consequences of posting to groups and selling material, see §9.4 (watching porn videos by yourself is your own business). The beneficiary is you.

Evidence grade

B : Supported by research but without a precise number, or based on small or single studies.

Sources

1. Rider JR, Wilson KM, Sinnott JA, et al. (2016). Ejaculation Frequency and Risk of Prostate Cancer: Updated Results with an Additional Decade of Follow-up. European Urology, 70(6), 974–982. https://doi.org/10.1016/j.eururo.2016.03.027
2. Dimitropoulou P, Lophatananon A, Easton D, et al. (2009). Sexual activity and prostate cancer risk in men diagnosed at a younger age. BJU International, 103(2), 178–185. https://doi.org/10.1111/j.1464-410x.2008.08030.x
3. Grubbs JB, Perry SL, Wilt JA, Reid RC. (2019). Pornography Problems Due to Moral Incongruence: An Integrative Model with a Systematic Review and Meta-Analysis. Archives of Sexual Behavior, 48(2), 397–415. https://doi.org/10.1007/s10508-018-1248-x
4. Waldinger MD, Meinardi MM, Zwinderman AH, Schweitzer DH. (2011). Postorgasmic Illness Syndrome (POIS) in 45 Dutch caucasian males: clinical characteristics and evidence for an immunogenic pathogenesis (Part 1). The Journal of Sexual Medicine, 8(4), 1164–1170. https://doi.org/10.1111/j.1743-6109.2010.02166.x
5. Chea M, Teng M, Chesnel C, et al. (2023). Postorgasmic illness syndrome: one or several entities? A retrospective cohort study. The Journal of Sexual Medicine, 20(12), 1407–1413. https://doi.org/10.1093/jsxmed/qdad139
6. Xi GP, Yang RX, Zhang J, et al. (2023). Clinical characteristics, allergic response to autologous semen, and desensitization in patients with postorgasmic illness syndrome. Sexual Medicine, 11(6), qfad068. https://doi.org/10.1093/sexmed/qfad068
7. Ponce S, Chapalamadugu M, Levine S, et al. (2025). Treatments for postorgasmic illness syndrome: a systematic review. The Journal of Sexual Medicine, 22(7), 1236–1243. https://doi.org/10.1093/jsxmed/qdaf112
8. Duran MB, Rubin RS, Reisman Y, Serefoglu EC, et al. (2025). Recognition and practice patterns of sexual medicine experts towards postorgasmic illness syndrome. International Journal of Impotence Research, 37(6), 454–457. https://doi.org/10.1038/s41443-023-00753-x

Translated from the Chinese original. Original book, section 6, tip 27. Content may be out of date and rules differ by place. When you actually deal with an agency, a doctor or a court, follow what local officials, doctors and lawyers tell you. Disclaimer