Cool Tips for a Hot Season

by Food and Drug Administration (FDA)

Screening the Sun

The warmth of the sun may feel good, but basking in the rays is not healthy: Sunbathing not only ages your skin, giving it wrinkles and a leathery texture, it also increases your risk of skin cancer. The types of sunlight mainly responsible for sun damage are known as ultraviolet A (or UVA) and ultraviolet B (UVB).

UVB light turns skin red fairly quickly, causing a sunburn, says Sheryl Clark, M.D., assistant professor of medicine at the Cornell Medical Center. UVB light also causes changes in skin cells that can lead to skin cancer.

UVA light, long thought to be harmless "tanning rays," also contributes to the development of skin cancer. With enough exposure, UVA rays cause sunburn. In addition, since UVA light penetrates to the dermis, or second layer of skin, it is mainly responsible for the aging effects of sunbathing.

Your first line of defense against the sun should be a sunscreen. FDA regulates sunscreens as over-the-counter drugs. Most experts recommend using a sunscreen with an SPF (sun protection factor) of 15 or more. The sun protection factor tells how much longer you can stay in the sun before burning than when you're not using a sunscreen. For example, "SPF 15" means that you can stay in the sun 15 times longer than without protection before burning.

An SPF 15 sunscreen will filter out UVB light and at least some UVA light, according to Vincent DeLeo, M.D., assistant professor and director of environmental dermatology at Columbia Presbyterian Medical Center in New York City.

FDA has approved a few products containing Parsol 1789 for screening UVA light. The agency is evaluating the UVA light protection provided by other sunscreens, including oxybenzone and titanium dioxide, two of the ingredients approved for screening UVB light. Oxybenzone screens out only part of the UVA light that reaches the Earth's surface and, therefore, its effectiveness in preventing UVA skin damage is debatable. Titanium dioxide, on the other hand, reflects all light and is probably effective in preventing UVA-induced skin damage.

For added protection, cover exposed areas with opaque clothing and wear a wide-brimmed hat to protect your head and face. (Beach umbrellas and any material you can see through do not fully protect against the sun.) Try to stay out of the sun between 10 a.m. and 2 p.m., when the rays are strongest, and reapply your sunscreen often, especially after you swim or sweat.

If you're a parent, protect your children's skin: Research indicates that one or more severe, blistering sunburns in childhood or adolescence can double the risk of melanoma (a type of skin cancer) later in life.

Light Sensitivity and Medication

Be especially careful about sun exposure if you take medication. The combination of some drugs and sunlight can decrease the time necessary to promote rashes, sunburn, premature skin aging, or more serious consequences such as cataracts, blood vessel damage, skin cancer, allergic reactions, and reduced immunity. Although exposure to the sun alone can cause all these problems, certain drugs can increase your sensitivity to light, raising the chance that these adverse reactions will occur.

Some of the medications that can cause such photosensitivity are: antihistamines, coal and tar derivatives (dandruff shampoos, for instance), oral contraceptives containing estrogens, nonsteroidal anti-inflammatory drugs (such as ibuprofen), phenothiazines (major tranquilizers and anti-nausea drugs), psoralens, sulfonamides ("sulfa" drugs, for instance), sulfonylureas (oral anti-diabetics, hypoglycemics), thiazide diuretics ("water pills"), tetracyclines, and tricyclic antidepressants.

"Bronzers" and Tanning Pills

Products called "bronzers" are promoted as a way to get tan without the sun. These products contain FDA-approved additives (such as dihydroxyacetone) that interact with protein on the skin's surface to produce a color when applied to the skin, according to John Bailey, Ph.D., acting director of the division of colors and cosmetics in FDA's Center for Food Safety and Applied Nutrition. Though bronzers can give your skin a golden color, they do not provide any protection against the sun. Also, they can be difficult to apply; thus, your "tan" may be uneven, and the chemicals in the bronzers may react differently on various areas of your body, producing a tan of many shades.

About the Author

www.fda.gov
FDA is A United States government body that oversees medical devices, including contact lenses, intraocular lenses, excimer lasers and eyedrops. In the US, these products must be approved by the FDA before they can be marketed.