Tanning: More Than Skin Deep

Pity those golden-brown sun-worshipers: They're not just slaves to fashion, they also may be physically addicted to the sun.

In a study at Wake Forest University, researchers asked sun lovers to lie for 10 minutes in tanning beds, half with ultraviolet (UV) light and half without. Those deprived of a UV fix experienced nausea and jitteriness—symptoms that are an awful lot like narcotic withdrawal. UV light causes the body to release endorphins, the body's natural painkiller. Baking twice a week—in the sun or in a tanning bed—is enough UV exposure to cause dependence.

"People get a sense of relaxation after they tan," says Mandeep Kaur, a dermatologist and author of the study. "They don't realize it's that feeling, not the tan, that gets them returning to the tanning bed over and over again."

Fake the Bake

PT Staffers tested six popular sunless tanners. These three came out on top. But beware: Most faux tanners don't provide any protection from the sun.

4 stars: Neutrogena(R) Moisture Rich Sunless Tanner ($10.99)

Testers say: "The color is natural and it works right away."

3 1/2 stars: L'Oreal(R) Sublime Bronze Tinted Self-Tanning Lotion ($8.99)

Testers say: "Tint helps you apply it evenly, but it has a harsh smell."

3 stars: Jergens(R) Natural Glow Daily Moisturizer ($7.49)

Testers say: "Gradual buildup allows you to control the color."