DERMATOLOGY

More than a million people in the U.S. are diagnosed with skin cancer each year, but it is preventable with proper protection from the sun.

The sun is necessary for life, but too much sun exposure may lead to poor health. More than one million people in the United States are diagnosed with skin cancer each year. However, skin cancer is largely preventable if people protect themselves from the sun, so whether it's a cool day in January or a sunny day in July, the board-certified physicians of Treasure Coast Dermatology are here to help you play it safe outdoors.

Properly used, sunscreens offer protection from the sun's damaging ultraviolet (UV) radiation. According to recent surveys, many people are confused about the correct use and effectiveness of sunscreens. Sharing information to help clear up some cloudy issues, Drs. Tim Ioannides and Jonathan Sanders hope to enable readers to protect themselves against sun damage confidently.

Since 90% of all skin cancers can be attributed to the sun, sunscreen is an important part of any skin protection program.

"With the rate of skin cancer soaring, particularly in Florida, protecting the health of our skin has never been more important," notes Jonathan Sanders, MD, JD.

"Regular sunscreen use can inhibit squamous cell carcinoma, a form of skin cancer that kills between two thousand and five thousand Americans each year," notes Tim Ioannides, MD.

"In fact," explains Dr. Ioannides, "instead of just wearing sunscreen, people should also wear broad-brimmed hats and sun-protective clothing."

"Proper sun protection, including sunscreen, provides an intense, long-term benefit against squamous cell carcinoma," adds Dr. Sanders. "Remember: we're here to help people play it safe this season and every season."

The vitamin D conflict

Some recent reports have suggested that the benefit of sun exposure outweighs the risk because of our bodies' need for vitamin D.

Vitamin D deficiency can be a serious health problem, most notably by blocking the absorption of calcium and phosphorus. This can cause bone deterioration. While it is true that sunlight is the most abundant natural source of vitamin D, research has shown that vitamin D deficiency does not result from ongoing regular sunscreen use. Vitamin D supplementation may be a good idea for some people. Anyone concerned about getting enough vitamin D should consult a physician.

Proponents for sun avoidance encourage maintaining adequate levels of vitamin D through dietary sources and supplements without skimping on the sunscreen. This is a win-win situation, as people can have the benefit of vitamin D without the risk of exposure to ultraviolet radiation.

Sunscreen facts and myths

Myth #1: Sunscreen is not necessary when swimming or while outside on cloudy days.

The reality: Wear sunscreen even on cloudy days. Dangerous rays can reach you through clouds and water.

Myth #2: Wearing a cover-up allows you to skip your sunscreen.

The reality: Wearing a light-colored t-shirt is certainly better than going without any covering at all. Keep in mind, however, that a typical thin white t-shirt has a sun protection factor (SPF) of only about 7.

Myth #3: SPF 20 sunscreen allows you to stay in the sun all day.

The reality: The SPF helps determine what product is best for your skin type. If it takes you 20 minutes to burn without sunscreen, SPF 20 will allow you about 400 minutes in the sun (20 minutes x 20 SPF = 400 minutes) without burning.

Myth #4: Diligent use of sunscreens during the first 18 years of life reduces the lifetime incidence of some skin cancers.

The reality: An oft-quoted statistic is that Americans get most of their UV exposure during childhood, and therefore many adults have decided that they don't need sunscreen. According to a paper in Photochemistry and Photobiology by Dianne E. Godar, et al, "Careful analysis of UV exposure data shows that Americans actually get less than twenty-five percent of their lifetime UV dose by the age of eighteen... Thus, a better educational approach for reducing skin cancers would be to instruct fair-skinned individuals to protect themselves throughout their lives from being exposed to too much UV radiation."

Which sunscreen is right for me?

Be sure to use a sunscreen that blocks both UVA and UVB rays and offers at least SPF 30. Some of the best sunscreens contain titanium dioxide or zinc oxide.

More expensive products are not necessarily better. Ask your doctor or pharmacist about specific brands. Keep in mind the following general rules.

Waterproof sunscreen protects you from the sun for up to 80 minutes in water. Water-resistant means you will only get about 40 minutes of protection.

If you have sensitive skin, use a product that says hypoallergenic on the label, and if you are acne prone, look for a product that is noncomedogenic .

Sunscreens should never be used past their expiration date. They may become less effective. Discard any unused sunscreen at the end of the year, and buy a new product.

How do I apply sunscreen?

Apply sunscreen 20 minutes before going out into the sun, or as directed by the manufacturer. This gives the sunscreen time to be absorbed into your skin.

Squeeze out an ounce (the amount to almost fill a shot glass). This amount will keep an average-sized adult protected. Coat your body in a thin, even layer.

Apply it all over. Applying sunscreen while you're completely naked helps to cover areas that may become exposed when your swimsuit moves around.

Reapply every two hours, or more often if you are swimming or perspiring.

Don't forget about your lips, ears, feet, hands, bald spots, and the back of the neck.

Skin cancer types

There are three main types of skin cancer: melanoma, basal cell carcinoma, and squamous cell carcinoma.

"Malignant melanoma, one of the most dangerous types of cancer, will claim approximately ten thousand lives this year," notes Dr. Sanders. "The majority of melanomas occur on the head, neck, arms, and back - areas of the skin that are most exposed to sunlight. Most are dark or black but may sometimes be lighter brown or even speckled. The surface is usually raised and sometimes rough. Melanomas are not normally circular in shape, but some can be quite close to a circle.

"The most common skin cancer, basal cell carcinoma, affects one in five Americans on average," adds Dr. Sanders. "These lesions tend to be shinier in appearance. The vast majority of basal cell carcinomas occur on the face. They start as a small, pink, pearly, or waxy spot, often circular or oval in shape.

"Squamous cell carcinomas are more scaly or crusty in appearance, and lesions called actinic keratoses often develop into them. Squamous cell carcinomas are most common on the limbs, head, and neck. They are pink and irregular in shape, usually with a hard, scaly, or horny surface, although they can sometimes become an ulcer. The edges are sometimes raised, and they can be tender to the touch."

"An annual dermatologic examination is similar to a mammogram or colonoscopy for cancer detection," says Dr. Ioannides. "Patients should not be satisfied with someone giving them a cursory exam; a physician's assistant should not replace the careful attention given by a physician. Regular evaluations by a board-certified dermatologist are crucial, and our offices strive to secure timely appointments for our patients because the sooner we catch skin cancers, the sooner we can treat them."