Dr. Oz says 1,000 units of vitamin D a day will benefit the body in a variety of ways. "Vitamin D is critically important for preventing cancer and critically important for reducing heart problems. It's linked to multiple sclerosis, to juvenile diabetes. It's one of the best ways of reducing infection rates. It's got a ton of things that it does for you to make your immune system function the way you want it to function."
Your body naturally gets vitamin D through sunlight exposure, so Dr. Oz says to get 10 minutes of direct sun exposure to your body or take a vitamin D supplement once a day.