Cancer Specialist Discusses the Dangers of Sun Exposure and Tanning Beds

According to the Skin Cancer Foundation, skin cancer is the most common type of cancer worldwide. In the U.S. alone, more than 9,500 people are diagnosed with skin cancer every day, and more people are diagnosed with skin cancer each year than all other cancers combined.

Michael Kasper, M.D., director of radiation oncology for Lynn Cancer Institute at Boca Raton Regional Hospital, says people who live in South Florida – especially those with significant risk factors – need to be extra careful about getting too much sun exposure.

Radiation from the sun’s powerful rays causes changes at the cellular level of the skin, he says, which can lead to the development of basal cell carcinoma, squamous cell carcinoma, melanoma and other common types of skin cancer.

An estimated 207,390 cases of melanoma, the deadliest type of skin cancer, will be diagnosed in the U.S. in 2021, the Skin Cancer Foundation says – an increase of nearly six percent from last year. “Having five or more sunburns doubles your risk for melanoma,” Dr. Kasper says. “But the good news is that, when detected early, melanoma is highly survivable.” The five-year survival rate for melanoma is 99 percent, according to the Skin Cancer Foundation.

Dr. Kasper spoke with Resource editors recently and answered some common questions about protecting one’s skin from the sun’s damaging rays.

Q. Why is it important to use sun protection year-round, not just in the summer?

Dr. Kasper: Daily use of physical sun protection on sun-exposed areas of the body such as your face, neck, hands, arms and legs is important every day of the year, not just in the summer. The sun is closer to the earth during the winter months, in fact, and in South Florida the sun’s rays are stronger than they are in northern latitudes.

Sunscreens are topical preparations that help protect against the sun’s ultraviolet (UV) rays, which damage the DNA of the skin. Many people get a false sense of security from sunscreens, believing they block all of the harmful rays. Sunscreens only protect against some of the sun’s rays, however, which means it’s especially important to also wear sun-protective clothing, hats and glasses, and to avoid sun exposure during peak hours.

Q. What would you tell people who believe that sunscreens are bad for bone health because they block the absorption of Vitamin D?

Dr. Kasper: Vitamin D is a source of skin creation from sun exposure. It was hypothesized that, since sunscreens absorb the UVB rays that can cause, they may correlate to a relative deficiency of Vitamin D. The bulk of scientific evidence does not support the notion that this is common problem, however. Remember, in Western societies the primary source of vitamin D is diet. And rickets, a true deficiency of Vitamin D that softens and weakens the bones in children, is something we hardly ever see any more in the United States.

A two-year study of sunscreen users showed that sunscreens do not lead to Vitamin D deficiencies with bone-related side effects. The bottom line is that sunlight is a known carcinogen and causes more cancers than anything else, so intentionally exposing our bodies to sun in the name of Vitamin D is unwise. You can get all the Vitamin D you need in a daily vitamin. 

Q. What about tanning beds? Are they safe?

Dr. Kasper: As long as tanned skin is seen as healthy, we can expect to see an increase in indoor tanning. But there is no safety in tanning beds. First of all, there is very little regulation of indoor tanning salons, so there is great variability in operator safety. Secondly, long-term exposure to tanning beds can trigger molecular alterations believed to cause skin cancer, similar to outdoor sun exposure.

You need to ask yourself if the end justifies the means, in that a tan will fade in a few weeks but the harmful effects of photoaging of the skin are everlasting. If you want wrinkled, discolored, leathery skin when you’re older, you’ll definitely get it from tanning beds.

Some people also think, incorrectly, that they can minimize the risk of a sunburn by getting a “base tan” at the tanning salon. Studies have shown that getting many small doses of UV light exposure over time – such as those an indoor tanner might receive – is more carcinogenic than the sunburn a vacationer might experience.