Sunshine and skin cancer: the real story

You hear a lot of warnings that too much sun may give you skin cancer. Other than smoking, this is one of the few cancer prevention ideas mainstream medicine gets excited about.

    It's too bad they don't use their resources and all those public service TV and radio commercials for something more worthwhile. The cancer danger from ultraviolet rays is pretty small.

    The best evidence I've seen indicates that sunshine may cause mild, practically harmless basal cell carcinomas. Almost nobody ever dies of this type of skin cancer, although it can blemish the skin. The deadly type of skin cancer is melanoma and, surprisingly, the evidence isn't conclusive on whether UV rays cause melanoma. In any case, very few people die of melanoma.

    Now, I'm not saying go out and get as tanned as you want. Too much UV exposure does age the skin and most likely causes the mild form of skin cancer. What's more, the damage from the tans and burns we get when we're young doesn't show up for decades. It's a case of "enjoy now, pay a terrible price later."

    So assuming you don't want dry, wrinkled skin and nasty little black lesions when you're an old coot like me, you should keep your sun exposure brief and moderate. Boosting your vitamin D levels is the only real health reason to take in UV rays, and a little bit of exposure (well short of what it takes to give a white person a tan) is plenty for that purpose.

But there's another danger here,
and it doesn't come from the sun. . .

    Conventional medicine's "cure" for too much sun may be worse than the disease. Some researchers are just as concerned about sunscreens as a potential carcinogen as they are about UV rays.

    I've been warning about this possibility for years. There have been few or no long-term studies on whether it's safe to slather sunscreen chemicals all over our bodies. But people think, "Surely the government checks out all these products." Right.

    I see young parents covering infants and toddlers with sunscreen from head to toe. It's scary.

    Now there's some evidence my hunch may be right. Cell toxicity studies conducted by researchers at Missouri University of Science and Technology suggest that a common sunscreen ingredient, zinc oxide, may be at the root of the problem.

    Dr. Yinfa Ma, Curators' Teaching Professor of chemistry, led research studies which found that exposing this ingredient to sunlight causes a chemical reaction that may release unstable molecules known as free radicals.

    According to the study published in the Journal of Toxicology and Applied Pharmacology, as free radicals try to bond with other molecules, they cause cell damage that could increase the risk of skin cancer.

    Dr. Ma's team also theorized that the longer zinc oxide is exposed to sunlight, the greater damage it causes to human cells.

    If this study is accurate, then using sunscreen to protect your body from UV rays could speed up the formation of cancer-causing free radicals.

    But the study authors caution against jumping to conclusions. Dr. Ma noted that this study was just a beginning and additional research is needed.

    No doubt that's true, but I haven't used sunscreen for years (I don't like the stuff anyway). I recommend avoiding it and taking the following steps instead:

• Cover your skin with light clothing (but not too light; the rays can penetrate extremely sheer material)
• Seek shady spots when you're outdoors
• Get your exposure at times of day when the sun is not so intense (morning and evening); during the summer, 10 AM to 2 PM is generally the time when the sun is most intense and you can fry really fast
• Eat plenty of antioxidant-rich fruits and vegetables to help fight free radicals
• Apply skin care products enriched with green tea, vitamin C or other antioxidants to the outside of your skin. I've read that a mixture of vitamin C in water, applied to the skin, is a good sunscreen. I haven't tried it.

    These solutions may sound simple and "un-medical" — they don't come out of pharmacy. But sometimes the most effective solutions don't have to be complicated at all!

Now, about that cancer-causing nail polish. . .

    At the 2012 Democratic National Convention, the First Lady sparked a fashion craze by wearing a unique shade of blue-gray gel nail polish.

    Nail salons nationwide reported an uptick in clients searching for this long-lasting, chip resistant polish.

    Because gel nail colors require a UV light source to dry and seal the color, they're mainly applied by the pros. But some manufacturers have created home kits that include a mini UV lamp to help you achieve the same look at home.

    Many women love these gel colors because some can last as long as three weeks! But that kind of durability makes it harder to remove the polish too.

    You have to soak your nails in acetone for10 to 15 minutes to remove the polish. That sounds like a bad idea to me, right off the bat. The acetone can dry your nails… irritate the skin near your nails… and even escalate to form rashes or blisters on your skin!

    An American Academy of Dermatology press statement cites one study in which dermatologists examined five women who complained of weak, brittle and thinning nails that they suspected were caused by gel manicures.

    The dermatologists agreed that their problems were likely a result of the gel manicures.

    What's more, one of the women underwent two additional tests to measure the nail plate before and after one gel manicure. These tests confirmed that nail plate thinning occurred.

So what's the cancer connection?

    Gel nail polish may pose a cancer threat on two levels…

    First of all, some of these polishes contain the chemical preservative butylated hydroxyanisol (BHA), which the National Institutes of Health (NIH) have found to be a consistent cause of tumors in laboratory animals.

    Likewise, the International Agency for Research on Cancer classifies BHA as a possible human carcinogen.

    Scientists are not sure how much exposure you would need for cancer to develop, but it's wise to be cautious.

    Not all gel polishes contain this chemical, so be sure to check the ingredient list on any bottle you plan to use.

    The second potential cancer threat from gel manicures has to do with the application process. Remember that gel polish applications require a UV lamp to set. Does this UV exposure pose a cancer danger? At least one conventional expert thinks so. . .

    Dr. Susan Taylor, dermatologist and clinical researcher, said that exposure to this UV light for just four to eight minutes every two weeks can wind up being a significant level of exposure.

    I'm skeptical that the UV angle of this nail polish is much of a problem. Are women going to get melanoma lesions on their fingertips from a brief UV exposure? I suspect not. But, as I said before, it ages the skin and may also cause less deadly types of skin cancer. And who needs that?

    Dr. Taylor has three recommendations for people who prefer gel manicures to traditional nail polish:

• Apply an SPF 30 or higher sunscreen directly to your hands and fingers after you wash them midway through the manicure. (Obviously, I don't agree with her on this.)
• Cut the tips off a pair of cotton gloves and wear these while applying polish and during the time your fingers are under the UV light. This isn't a bad idea.
• Find a manicurist that uses LED (light emitting diode) light to set the gel polish.

Like many beauty treatments (hair dyes, for example — see Issue #272) this one sounds like more risk than it's worth. Your move. .