Some think turning light skin darker gives off an aura of good health. But a suntan actually signals skin damage. When exposed to the sun's ultraviolet radiation, the skin produces a pigment called melanin to protect itself from burning. And while indoor or "sunless" tanning may seem like convenient alternatives, especially during the winter months, these practices may not be risk-free. Before stepping into a tanning booth or buying over-the-counter (OTC) tanning products, consider these facts.