For years, doctors have been telling people to lather on sunscreen before going in the sun to prevent cancer.

But now, some researchers say there is substantial evidence that Vitamin D, which the body produces when exposed to the ultraviolet rays of the sun, can help prevent some types of cancer such as prostate, lung, colon and, ironically, skin cancer.

The researchers say people do not get enough Vitamin D and the best way to get the nutrient is through the sun, not food and supplements.
They say people need about 15 minutes a day without sunscreen, a few days a week.

The American Cancer Society says it is compelling evidence, but still more conclusive studies are needed before they change their recommendations.

The American Academy of Dermatology says "prescribing sunshine is highly irresponsible." The president of the academy says people get enough Vitamin D through incidental exposure to the sun. The academy stands by its recommendation that people should apply sunscreen before going out in the sun.