UV light exposure to the skin is the bodies primary means of vitamin D production, a major factor in the flight against, bone diseases such as osteoporosis.
Nature's Skin Protection:
Tanning is your bodies natural protection against burning. Unlike some sunscreens, a tan provides reliable full spectrum UVA/UVB protection against burning. Your natural tan provides protection that does not rub, sweat or wear off the way sunscreen protection can.
Prevention of Some Cancers:
Current research suggests people who regularly expose themselves to UV light experience lower incidence of death from ovarian, breast and colon cancers than whose who live in places with less sunlight, such as Alaska.
Seasonal Affected Disorder (SAD)
The National Institute of Mental Health has produced evidence that the shortage of sunlight during winter produces clinical depression in millions of people. Exposure to sunlight or simulated sunlight for 10-20 minutes once or twice a week show a 70% improvement in patients with seasonal affected disorder (SAD). Light treatment is the only known cure for the "winter blues".