Good news for men and mothers of teenage boys: a new study has proven that frequent ejaculation could result in a decreased risk of prostate cancer. The study, conducted by Jennifer Rider, ScD, MPH, an epidemiologist at the Harvard T.H. Chan School of Public Health in Boston, provides our “strongest evidence to date” for this oft-cited fact.

According to Medscape, Rider and her team used data from 32,000 men, followed over 18 years in the prospective Health Professionals Follow-up Study. Over time, 3,839 men in the study were diagnosed with prostate cancer, and 384 died.

Participating men reported their average monthly frequency of ejaculation at various ages so the researchers could compile a lifetime average. From the averages, they calculated a 20% reduction of risk in men who ejaculated 21 times per month compared to men who did the deed 4-7 times/month.

Dr. Rider cautions not to “dwell on the exact numbers of ejaculation, but instead should focus on the dose–response relation.”

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