[DIGEST: Psychology Today, Medical Daily, Live Science]

The health benefits of regular masturbation have been well-documented (and controversial) for decades. Now, there is good news: frequent masturbation could aid in preventing prostate cancer. An 18-year long Harvard University study in which 31,925 men chronicled their ejaculation frequency revealed a33 percent risk reduction in prostate cancer among those men who ejaculated at least 21 times per month. The study focused on men aged 20-29 and 40-49.

"These findings provide additional evidence of a beneficial role of more frequent ejaculation throughout adult life in the etiology of PCa [prostate cancer], particularly for low-risk disease," wrote the researchers from Harvard T.H. Chan School of Public Health, in the study.

Although these results are encouraging, scientists remain uncertain about why frequent self-pleasure is such an effective prevention method. Some researchers believe that male orgasms flush pro-inflammatory toxins, including carcinogens from cigarettes, out of the prostate gland, but this is yet to be proven.

The prostate is a walnut-sized gland located a couple of inches inside the rectum. During a male orgasm, it produces a fluid that mixes with sperm, creating semen.Prostate fluid is slightly acidic and contains enzymes, including zinc and citric acid. One of the main components of prostate fluid is PSA, or Prostate Specific Antigen. PSA is often elevated in men who have prostate cancer and can be detected via routine testing, which doctors recommend for all men over 50. As men age, the prostate can become enlarged, causing urination to become strained and erections to become difficult to achieve or maintain.

Prostate cancer is the most common cancer in men besides skin cancer. It affects one in seven men, with 60 percent of cases occurring after age 65 and the average age being 66. Prostate cancer is rare in men under 40. Although frequent masturbation may help prevent prostate cancer, healthy diet and exercise along with routine check-ups are essential to preventing illness.

Fortunately, prostate cancer has a very high survival rate when compared to other cancers: 99% of men will survive 5 years after diagnosis. Ten-year survival rates are 91%, while 15-year survival rates are 76%. Testing and early detection are crucial to increasing one’s chance of survival. Depending on the state of the disease, there are non-invasive and surgical treatment options available.