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What's the one thing you can do to improve your skin?

Getting Beautiful Skin Image Gallery If there's one thing that'll help keep your skin baby-smooth and healthy, it's sunscreen. See more getting beautiful skin pictures.
Ken Wramton/Photodisc/Getty Images

You're going to be stranded on a desert island with a single skin care product. What do you bring?

OK, not the most likely scenario, but it illustrates a point: Some products are more crucial than others. With all the skin care options on the market these days, it's hard to imagine picking just one. A daily regimen (for females, at least) can consist of five or six products. How can you pick a solitary bottle from all the serums, creams, lotions, spot treatments and cleansers for dry skin, acne, uneven tone, oiliness, fine lines and wrinkles?

It's actually not that hard. One product can single-handedly preserve your beauty, save your life, and should be used by everyone regardless of age, skin type or gender.

It's sunscreen, and it's the single most important thing you can do for your skin, even if you're only stranded in your house. Sun exposure is responsible for many of the visible signs of aging, like wrinkles and age spots, and it also can lead to the most deadly form of skin cancer. Applying sunscreen daily can provide serious long-term benefits.

Yet most people leave their skin unprotected. One-third of U.S. adults never wear sunscreen, and almost the same number don't put it on the kids before they head out to play [source: Hellmich]. This despite the fact that doctors diagnose 1 million new cases of skin cancer each year in the United States, and antiwrinkle treatments are a $1.6 billion industry [sources: AAD, Harmon].

In this article, we'll find out exactly why sunscreen is such a crucial addition to any skin care arsenal, see which kind is best one for your particular skin type and learn how to properly apply the stuff so it actually protects your skin from sun damage.

We'll begin at the surface of the issue: Sunscreen makes skin look better, and look better longer.