None, unless you like a persistent cough, yellow teeth, a mouth that tastes like an ashtray, and never having money. I've been a smoker for 21 years now so don't think these comments are from a non smoker.
Absolutely NONE! I lost my mother, as well as a very dear friend to smoking-related lung cancer. Let me tell you now, cancer is a slow, painful, ugly way to die. And before Mom died, she also became legally blind--she had macular degeneration; the doctor told her smoking would accelerate the damage. She didn't listen.