There's evidence that some vitamins can help protect your skin from -- or even reverse -- sun damage.

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It's a story as old as time. The allure of the forbidden is too tempting, and it's human nature to disobey the rules. So it was with Eve and the Tree of Knowledge, and so it is with us and the sun.

We've all heard about the importance of marinating ourselves in sunscreen all day, every day, and we know that we're supposed to stay out of the rays when they're at their strongest. And yet, many of us choose to bask in the sun anyway. It's hard to believe that something that can feel so good can do so much harm.

We have to see sun damage to believe it. Sunburn is easy to see and easy to learn from. It's bright pink and painful, and if it's bad enough, you'll have blisters -- and remember the SPF the next time. But most sun damage doesn't show up until later in life, in the form of wrinkles, uneven coloring, age spots (which should really be called sun spots), roughness and sagging skin.

That's what we call photoaging: the cosmetic effects of sun damage that add years to your look.

The sun emits two kinds of UV radiation that affect your skin: UVA and UVB rays. The trick to remembering the difference between the two is that UVA ages skin and UVB burns it. With their powers combined, the damage can be significant.

Physicians have been fighting the idea of a "healthy" looking tan for decades, but it hasn't seemed to sink in. Here's the deal: If the sun has darkened your skin, it's because your skin cells are trying their darndest to produce as much protective melanin as possible. Your skin is hurt, and the tan is the Band-Aid.

People with naturally red hair, pale skin, light blue, gray or green eyes, or a history of sunburn are at the greatest risk for serious sun damage, but it's a myth that only light-skinned people have to worry about sun exposure -- a dangerous myth. Far fewer African-Americans than whites or Hispanics have melanoma diagnosed at an early stage, possibly because it's commonly believed that black skin is safe from the sun [source: Skin Cancer Foundation].

Uneven pigmentation and wrinkles from sun damage do not discriminate based on skin color. But are we fooling ourselves with the vitamin-packed skin care products we use to try to turn back the hands of time?