What are the dangers of sun exposure?
The immediate danger of too much sun is sunburn. If you looked at sunburned skin
under a strong microscope, you would see that the cells and blood vessels have
been damaged. With repeated sun damage, the skin starts to look dry, wrinkled,
discolored, and leathery. Although the skin appears to be thicker, it actually
has been weakened and, as a result, it will bruise more easily.
However, the sun's most serious threat is that it is the major cause of skin
cancer, which is now the most common of all cancers. Doctors believe that most
skin cancers can be avoided by preventing sun damage.
Does the sun have benefits?
You may have been taught as a child that you need sunlight for your body to make
vitamin D, because vitamin D is not found naturally in most foods. But today,
many foods are fortified with vitamin D during the manufacturing process. Thus,
sun exposure is not as important for the body's vitamin D supply as it used to
be. Of course, being outdoors makes most people feel good. And playing tennis is
better for your health than watching television. But you can still protect
yourself from the sun's damaging effects while enjoying yourself outdoors.
How can I avoid the harmful effects of the sun?
Staying out of the sun is the best way to avoid sun damage, but most of us go
outdoors regularly. So when you go outside, take these precautions:
- Most importantly, always wear sunscreen. You should put it on every day.
Make it a habit, such as brushing your teeth.
- Try to avoid sun in the middle of the day, from about 10 am to 3 pm. The
ultraviolet rays, which cause sunburn, are strongest during this time.
- When you do go outdoors, especially for long periods in the middle of
the day, wear protective clothing. Long sleeves and slacks, as well as a
wide-brimmed hat, help protect your body against the sun's harmful effects.
- Wear sunglasses that filter UV light.
What is SPF in a sunscreen?
SPF stands for sun protection factor. The SPF number tells you how well the
product will protect you from UVB, the burning rays of the sun. (Most sunscreens
also absorb ultraviolet "A" rays, or UVA.) The larger the SPF number, the
greater the amount of protection. Everyone should use a sunscreen with an SPF of
at least 15. If you have had a skin cancer or precancer, you should use a
sunscreen with an even higher SPF. Many of the new sunscreens have SPFs of 30, 45, or higher.
I don't burn very often. Does this mean I can use a sunscreen with a low SPF?
If you were only trying to avoid sunburn, the answer would be "yes." But
protection from sunburn is not the most important reason for wearing sunscreen.
You want to reduce damage from the sun. Your skin can be harmed by constant sun
exposure, whether or not you see a burn. Remember, sunburn is an immediate
reaction, but damage from the sun occurs over a lifetime. If you have had a skin
cancer or pre-cancer, you should use an SPF of 15 or higher. (Some dermatologists
recommend that almost everyone use a sunscreen with an SPF of 15.)
Who should use sunscreens?
Anyone who spends time outdoors should use a sunscreen. This includes:
- men, women, and children
- people who tan easily and those who don't
- fair-skinned and dark-skinned people; people who already have tans and
- sunbathers, gardeners, and skiers.
Are sunscreens safe for children?
Yes. Not only are sunscreens safe for children over age 6 months, if used
regularly in childhood they can prevent skin cancers from developing in later
life. Recently, a researcher reported that if sunscreens were used regularly by
children through the age of 18, there would be a 72% reduction in the cases of
skin cancer later in life.
How should sunscreens be applied?
Sunscreens are very effective when used properly. Follow these guidelines to give yourself the most protection:
- Apply the sunscreen at least 20 to 30 minutes before you go outdoors,
whenever you will be exposed for 30 minutes or more.
- Reapply sunscreen every 3 hours while you are outdoors, even if the
product is labeled "all-day." If you are getting a lot of sun or perspiring
heavily, reapply sunscreen every hour or two.
- Cover all exposed areas, including your ears, lips, face and back of your hands.
- Don’t skimp; apply a generous layer. Smooth it on rather than rub it in.
A rule of thumb is that 30 ml (a shot glass) of sunscreen is necessary for
application to all exposed skin to attain the stated level of protection.
- Women should apply sunscreens under makeup. If you wait to apply
sunscreen until you hit the beach, you may already be perspiring, and
moisture makes sunscreens less effective.
My skin is sensitive. Should I skip the sunscreen?
Some sunscreens contain ingredients that may irritate the skin. If you know you
react to specific ingredients, be sure to check the contents on the label. You
can also ask your dermatologist to recommend a sunscreen.
However, the sunscreen may not be causing the reaction. Other products that
come into contact with your skin, including perfumes, certain medications, and
soaps, may make your skin more sensitive. Think about the products you have been
using (especially new products), and stop using these one by one before you stop
using the sunscreen. If you are not sure about the side effects of a medication
you are taking, consult with your doctor or local pharmacist.
Lim Henry W. Photoprotection and Sun Protective Agents. In: Wolff K, Goldsmith LA, Katz SI, Gilchrest B, Paller AS, Leffell DJ et al, editors. Fitzpatrick’s Dermatology in General Medicine. 7th ed. New York, NY: McGraw Hill Medical; 2008:Chap 223.
Tung R, Vidimos A.Melanoma. In: Carey WD, ed. Cleveland Clinic: Current Clinical Medicine 2010. 2nd ed. Philadelphia, Pa:
Saunders Elsevier; 2010:section 3.
Tung R, Vidimos A.Nonmelanoma skin cancer. In: Carey WD, ed. Cleveland Clinic: Current Clinical Medicine 2010. 2nd ed. Philadelphia, Pa: Saunders Elsevier; 2010:section 3.
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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or health care provider. Please consult your health care provider for advice about a specific medical condition. This document was last reviewed on: 3/16/2011…#5240