Weekender: The Damage Done Under the Sun

To tan or not to tan – that is the question. Given the long-standing prejudice against ‘people of color’ – it’s ironic that people without much color to their skin risk their health to acquire more. And now it turns out that the cancer-causing damage done to the skin through exposure to the sun – which begins a second after you step outside your door for an innocent, unprotected stroll on a beautiful day – continues even hours after the exposure has ended.

‘Why?’ you may ask? It’s because melanin – the pigment that gives color to the skin and hair and is known to help block the damage created by ultraviolet rays – turns out to create its own kind of damage to the DNA beginning hours after exposure to UVA rays.

That’s the conclusion reached by a researchers at the Yale University School of Medicine. The scientists found that ultraviolet light can generate molecules that energize an electron in melanin, which gets transferred to the DNA and bends it strands so they can’t be read properly.

Biophysicist Douglas Brash, who co-authored the team’s report [featured in the 2/20/15 issue of the journal Science], explains that, "This is like the chemistry seen in fireflies. It’s not that the skin is glowing, but it’s the same in the sense that chemistry is exciting electrons. This is not something that’s been seen in mammals before."

Fortunately, Brash and his colleagues noted that the energy transfer from the melanin to the DNA occurs slowly. Thus, "a protective strategy might involve finding small molecules that can enter the skin and keep energy from going into DNA, instead dissipating it away as heat." Vitamin E, and chemicals akin to potassium sorbate (widely used as a food preservative), appear to be possible candidates for helping prevent DNA damage from occurring if applied after time in the Sun.

But wait! Don’t we need Vitamin D for strong bones and the health of our immune system? Of course we do – which is why some scientists tell us that running from the sun is actually harmful to our health and that we need a least some regular and direct exposure.

Not so, say most dermatologists and cancer groups, including the Skin Cancer Foundation. And now the Department of Dermatology at Boston University’s School of Medicine has joined those who say you’re better off drinking your Vitamin D in fortified milk or orange juice, consuming it in salmon or taking a supplement rather than receiving it through your skin from the sun. That’s because getting Vitamin D the natural way accelerates aging, sagging, wrinkling, brown spots, and skin cancer. What a trade-off!

Deon Wolpowitz, MD, PhD, and Barbara A. Gilchrest, MD, the authors of a study on the subject reviewed massive research on Vitamin D and sun exposure – including arguments for its necessity. Those arguments, they found, were not so well founded whereas UV rays are an officially recognized environmental carcinogen. And each year, approximately 1.3 million people are diagnosed with skin cancer in the U.S.

Given that very small amounts of sun exposure precipitate all the Vitamin D the body can manufacture, too much Vitamin D can cause abnormally high blood calcium levels leading to an array of health problems, and even with sunscreen on enough UV reaches the skin to produce Vitamin D, Drs. Wolpowitz and Gilchrist conclude that, "The tradeoff of vitamin D production today for photoaging and skin cancer decades hence may have made sense millennia ago, when life expectancy was 40 years or less, but it’s a poor exchange when life expectancy has doubled, skin rejuvenation is a $35 billion/year industry, and one in three Caucasians develops skin cancer."

This brings us now to the issue of sun block – except that manufacturers can’t use that word anymore. Nor can they claim their product to be waterproof or sweat-proof. They are not allowed to say that protection begins the instant the product is applied – or that it lasts beyond two hours without reapplication – unless they have proven to the FDA that this is so.

When it comes to your own risk/benefit analysis of sunscreen, do your research. And make sure that whichever brand you determine is safe for you, it offers ‘broad spectrum’ protection against both UVA and UVB rays. Despite the fact that UVA makes up 95% of the radiation that penetrates the Earth’s atmosphere, sunscreens that are not ‘broad spectrum’ are more likely to offer protection against UVB.

Oh – and don’t forget your hat and gloves next time you go out for a stroll.

Story by Laurel Airica. Visit My Website, LaurelAirica.com.