Australian scientists found that men who masturbated frequently in their twenties---five times a week or more---had a 33 percent lower risk of prostate cancer late in life. The study showed that the more men ejaculated beween ages 20 and 50, the lower their risk of prostate cancer. Previous studeis showed that having multiple sez partners increased tha iisk of prostate cancer. Sexual intercourse increases the risk of infection, which can trigger prostate cancer growth . The Australian study examined the effects of all ejaculations---including masturbation. (NewScientist, July 16 2003)