Take vitamin D, the “sunshine” vitamin, so named because it is produced primarily in the skin through a chemical reaction that requires ultraviolet light. Increasingly, nutritionists recommend that you boost your daily intake because of vitamin D’s potential to help fight certain types of cancer.

In fact, many expect the next version of the Dietary Guidelines for Americans, due in 2010, to raise the amount currently recommended from 200 International Units (IU) for adults to 400 or more. But any advice that encourages exposure to sunlight concerns dermatologists, since rates of basal cell carcinoma, the most common type of skin cancer, have tripled in the past 30 years.

CNN.com