My friends tell me it can, but I just wanted to verify it with a real doctor. When it comes to talking about sexuality, embarrassment is one of the primary reasons why myths and misinformation spread like wildfire. No, masturbation does not cause blindness, pimples, hair growth on the palms of your hands, warts or insanity. In fact, it does not cause most, if not all, of the dozens of ailments attributed to it.
Masturbation is a completely normal, healthy activity.
That's not to say you would be unhealthy if you didn't masturbate. The point is that you shouldn't feel guilty, ashamed or evil if you do. Many children and most teenagers masturbate. Obviously, you're old enough to be talking about this with your friends and that means you're old enough to have some frank and open discussions about sexuality with your parents. You probably have a thousand questions for them, and you may be afraid to approach them.