Don't forget to protect your lips from the sun, which can cause cancer and signs of aging.

©iStockphoto.com/Biliana Rakocevic

Even if you get to the pool and slather sunscreen on your face and body before you spend the day in the sun, you've likely forgotten something important -- your lips. Using a sunscreen on your lips protects you in two ways. First, because the sun ages skin (lips included), the sunscreen keeps your lips feeling and looking healthy and vibrant. Second, skipping the sun protection in your lip products puts you at an increased risk of getting skin cancer or another skin condition [source: Dahl].

Sun damage leads to skin losing some of its elasticity, and unprotected lips are no exception. Also, lips naturally have thin skin, and sun damage can make the skin appear even thinner [source: Dahl].

Lips damaged by the sun's ultraviolet rays might also develop a condition called actinic cheilitis, or lip inflammation. This causes dry, rough, scaly lesions ranging in size from a pinhead to a quarter or more. Actinic cheilitis patches can range from skin-colored to a reddish brown shade, or sometimes appear as a whitish, scaly discoloration. Actinic cheilitis can also be a precursor to skin cancer and should be treated by a dermatologist [source: AAD: Actinic Keratoses].

If you like to add luster to your lips with lip gloss, know that some dermatologists say lip gloss without SPF might increase the possibility of developing skin cancer by acting as a kind of magnifying glass for the sun's rays. You might want to consider using a lip gloss with SPF, layering a lip product with SPF of at least 30 underneath or foregoing the lip gloss completely and switching to a matte lip product with SPF [source: Dahl].

No product with SPF can completely protect you from damaging rays. SPF 15 blocks 93 percent of ultraviolet B (UVB) rays. Up the SPF to 30, and you'll block 97 percent of UVB rays. Use SPF in your lip products even on cloudy days, and reapply often (at least once every two hours). Also, be sure to use a broad spectrum product that protects against both burning rays (UVB) and the rays that age your skin (UVA) [source: AAD: Skin Cancer].

Since sun damage builds up over time, it's never too late to start good practices to give your lips some sun protection. To learn how, visit the links on the next page for information.