Protecting Your Skin from Sunburn

Check out any beach in the United States on a sunny day. You'll probably find that most Americans still associate getting a tan with health and fitness. Of course, most of those who sunbathe have, by now, heard of the dangers of getting too much sun - sunburn, premature aging of the skin, and an increased risk of skin cancers. But many of those seeking the look of a bronzed jet-setter probably give little thought to the fact that a tan actually is the body's attempt to protect itself from the sun's damaging rays.

Sunburn is the result of overexposure to the sun's ultraviolet radiation - UVA (320 to 400 nanometers) and UVB ( 290 to 320 nanometers). Repeated exposure to UV radiation both tans and damages the skin.

The UV content of sunlight varies. It is greater at higher elevations because it's not filtered out by clouds or haze. Reflected ultraviolet light from snow, sand, water and other highly reflective surfaces can burn as severely as direct sunlight.

It has long been known that UVB is a cause of sunburn and plays a significant role in superficial skin cancers called basal-cell carcinomas and squamous-cell carcinomas. Research on the relationship between sunlight and melanoma - the most serious type of skin cancer - is less clear-cut. Studies suggest that those exposed to occasional periods of intense sunlight, like indoor workers who spend vacations lying on a beach, are at greater risk of melanoma compared with farmers, roofers and others who regularly spend long hours in the sun.

UVA radiation also may contribute to cancer. It penetrates into the deeper layers of the skin and can impair the skin's immune system. Most commonly, UVA causes the leathery, sagging, brown-spotted skin of those who spend a lot of time in the sun. Tanning beds also emit high doses of UVA. The longer waves of UVA also can penetrate window glass, including car windows.

Sunscreens
Shopping for skin products that offer protection from the sun can be confusing. And labels that feature superlatives such as "total sunblock," "waterproof," "all-day protection" and "deep- tanning" provide little solid information for those seeking the best protection for their skin type.

In an effort to help consumers, the Food and Drug Administration (FDA) is implementing new regulations that create just three categories of sunburn protection:

• Minimum - corresponds to the current sun protection factors (SPF) of 2 to 12.
• Moderate - corresponds to SPF of 12 to 30.
• High - corresponds to SPF 30 or more. SPF ratings refer only to UVB protection.

It's important to check sunscreen labels to ensure that the product is a "broad-spectrum sunscreen" that also offers protection from UVA. Products containing micronized zinc oxide, titanium oxide or avobenzone (Parsol 1789) are among those that provide protection against both UVA and UVB.

SPF ratings are based on how much longer someone may be protected from sunburn than if no sunscreen were applied. For instance, if someone normally would burn in 20 minutes of sun exposure, a product with a SPF of 15 would protect that person from burning for 5 hours, assuming the sunscreen was applied properly.

MayoClinic.com asked Lisa A. Drage, M.D., a dermatologist at Mayo Clinic, Rochester, Minn., to discuss the latest research on the sun's effects on skin and the FDA's new labeling regulations for sunscreens.

There has been some controversy recently about the use of sunscreens. Do you still recommend them?

Dr. Drage: Yes. Protection from the sun is very important in the prevention of both melanoma and non- melanoma skin cancers. To be most effective, protective steps should be started in early childhood. But all people, regardless of age, should practice sun- protection. It's the sensible thing to do. The regular and correct use of broad-spectrum sunscreens is the key part of a program to prevent sunburn, sun damage and skin cancer. Other components include sun-protective clothing (broad-brimmed hats, long sleeves, sunglasses) and sun-smart behaviors (avoiding sports or outdoor activities during the hottest hours of the day.)

What are some important points for people to know about sunscreens and the labeling changes?

Dr. Drage: We recommend the proper use of sunscreens with a SPF of at least 15 - 'moderate' under the new regulations. Probably the biggest problem with sunscreens is that people don't really know how to use them correctly. Recent studies indicate that people don't use sunscreens as frequently as they should and also don't apply a sufficient amount.

Labels of most sunscreens call for 'liberal and frequent' applications. A liberal application is 1 ounce - the amount in a shot glass - to cover all exposed parts of the body. That's more than most people put on. Timing is important, too. To have the best effect, sunscreens need to be applied 30 minutes before you get to the pool or beach, not after you arrive. And, people should reapply even water-resistant sunscreens every 90 minutes.

Tanning salons often advertise that their "tanning beds" are a good way to get a "base" tan prior to lengthy exposures to direct sunlight. Is this a safe way to prepare for a trip to Hawaii, for example?

Dr. Drage: There is no such thing as a safe tan. Therefore, tanning beds are not safe - they are a factor in skin cancer and should be avoided. They also can be associated with other nasty skin problems, such as infections and warts.

We know that sunburns and UVB are associated with skin cancer and melanoma risk. But that doesn't let the UVA radiation in tanning beds off the hook. UVA probably has an effect on your skin-based immune system and its ability to fight melanoma. UVA radiation is not safe. The tanning salon operators say that UVA is good and UVB is bad. The research doesn't support that. Currently, we aren't absolving UVA from increasing the risk for skin cancer or melanoma.

What about so-called "bronzers" that make the skin look tanned?

Dr. Drage: I think that's an excellent way of getting the look without paying the price. They are safe. The one caveat is that many don't have sunscreen in them, and the 'tan' you get with them won't protect you from the sun. You still need to wear sunscreen. But, overall, they're a much healthier way to achieve the look without the risk. With experimentation, people can find a level of color that looks best on them.

Should people avoid the sun altogether?

Dr. Drage: We don't want people to stay in caves, they need to get out and have an active and healthy life. What we're promoting is smart sun behavior - wearing sun- protective clothing like a broad-brimmed hat, light- colored clothing that covers exposed skin and a broad- spectrum sunscreen. People also should save sports and other activities for the early morning or late afternoon.

Applying sunscreen to exposed areas is a good habit, year-round, in most localities. It should become a part of a person's routine, just like brushing your teeth. It's a multi-step way of approaching it.

We don't want to scare people, but at the same time, behavior does have an effect on health - whether it's cigarette smoking, diet or sun behavior.

For additional health related information, visit http://www.mayohealth.org.

Copyright, 2001, GoingToTheBeach.com, Inc.