The tanning industry has tried to cash in on the positive benefits that have been linked to vitamin D exposure. But any way you spin it, tanning is a bad idea. The ultraviolet radiation from sun lamps can be up to 15 times more powerful than the midday sun. The American Academy of Dermatology strongly opposes the use of tanning beds because they can increase your risk of melanoma, the deadliest form of skin cancer.

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