No, it doesn't blind you. And now medical researchers say it's not going to give you cancer either. Frequent ejaculation during masturbation or sex, a new study has found, isn't associated with an increased risk for prostate cancer, laying to rest a popular misconception. In fact, it may even decrease the risks for certain people. The research, published Tuesday in the Journal of the American Medical Association, is based on surveys of nearly 30,000 men from 1992 to 2000. The mostly white males, ages 46 to 81, provided histories of sexual intercourse, nocturnal emission and masturbation during their twenties, forties...