In one of the largest studies to date on the relationship between male
ejaculation and prostate cancer, researchers have discovered that more
frequent ejaculation may actually decrease a man's risk of developing the
The study by NIH researchers surveyed more than 29,000 men over an eight-
year period. The men were asked to estimate the average number of
ejaculations they had per month during their 20s, their 40s and over the
past year. The study was published in the April 7 Journal of the American
Medical Association (JAMA).
Results showed that men who had the most ejaculations per month—21 or
more—reduced their risk of developing prostate cancer by one-third
compared to men who reported having the fewest ejaculations (four to
seven per month).
Previous studies had suggested a link between sexual activity and
increased risk of prostate cancer, possibly due to higher levels of
testosterone or the presence of infectious agents, according to the April
7 San Francisco Chronicle. The NIH study—part of the Health Professionals
Follow-up Study, which looked at the health habits of 52,000 men—was the
first to track a large group of men for several years.
None of the men had cancer when the study began and researchers accounted
for differences in diet, exercise and other risk factors.