A number of studies have found a statistical connection between relatively frequent ejaculation and a reduced risk for prostate cancer. In one of the most comprehensive of these studies, from 2016, researchers at Harvard Medical School, Harvard T.H. Chan School of Public Health and Boston University School of Public Health found that men who ejaculated 21 times a month had a 20% reduced risk of developing prostate cancer compared with men who orgasmed four to seven times a month.

The researchers wrote that “ejaculation frequency may be inversely related to the risk of prostate cancer.” In other words, the more often a man orgasms, the less likely he is to develop prostate cancer. They followed 31,925 men from 1992 through 2010; 3,839 were eventually diagnosed with the disease.

In 2018, a meta-analysis of 22 studies, published in the Journal of Sexual Medicine, confirmed  the dose-response statistical association and provided additional findings. The researchers concluded that “men with fewer sexual partner numbers, older age at first intercourse and moderate frequent ejaculation were associated with a significantly decreased risk of prostate cancer.”

The mechanisms by which the secretion of semen may protect the prostate is not well understood. If frequent ejaculation does indeed prevent prostate cancer, it may work by “flushing out harmful chemicals that build up in semen,” Anne Calvaresi, DNP, CRNP, RNFA, the chair of the Urology Care Foundation’s Prostate Health Committee, wrote in the fall 2020 issue of the magazine UrologyHealth extra.

But it’s also possible that the association is the product of correlation rather than causation. “Men who ejaculate more may have healthier lifestyle habits that decrease their odds of being diagnosed with the disease,” Calvaresi wrote.

After skin cancer, prostate cancer is the most commonly diagnosed cancer in men. Approximately 174,600 men in the United States develop prostate cancer annually, and about 31,000 men die of the disease. Prostate cancer involves the formation of a malignant tumor on the prostate, a tiny organ located in the pelvic area that is not present in women.

Men who are older or Black or have a family history of prostate cancer are considered at higher risk for prostate cancer. Prostate cancer incidence may be lower in men who are HIV positive, but in recent years, it has been increasing in this population, especially among those between ages 35 and 64.

Beyond sexual activity, an overall healthy lifestyle has been associated with a reduced risk for prostate cancer. Preventive factors include maintaining a healthy weight, vigorous physical activity, not smoking, high consumption of tomatoes and fatty fish and reduced intake of processed meat. Coffee may also be protective. To learn more about screening for prostate and other cancers, click here.