Prostate Cancer
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In 2004, a study from the National Cancer Institute compared 50,000 men and found that those who had more than 21 orgasms each month were 30 percent less likely to develop prostate cancer than those who had fewer than seven. Another study in 2003 had 2,000 men report their ejaculation history from when they were younger. They found that men who reported more than five orgasms a week in their twenties had a one-third lower incidence of aggressive prostate cancer later in life. Researchers aren't positive about why this happens but there one theory is that ejaculating often clears the prostate of old semen that would otherwise turn carcinogenic.