Choosing a Sunscreen for Sweet Summer Sun
Sunlight, sunscreens, Vitamin D and Cancer…At first glance it may not seem like it but everything really is connected. When you initially think about sunscreen you probably think about sunburn and then your mind may or may not drift towards skin cancer prevention. That would be the natural flow because it has been drilled into our minds that sunburn is bad and can lead to cancer…and nobody wants cancer.
What hasn’t been drilled into our minds are the side effects of widespread sunscreen use. I’m going to talk about them below but before I do I want to explain some things about sunlight.
Many of the sunscreens available in the US today combine several different active chemical and physical sunscreen ingredients in order to provide broad-spectrum protection. Usually, at least three active ingredients are called for. These ingredients work to protect against UVB and UVA rays.
Here are the three categories:
UVB Blockers:
PABA derivatives, salicylates, and/or cinnamates such as octylmethoxycinnamate and cinoxate. – Trigger allergic reactions in some folks.
UVA short wave blockers:
Benzophenones like oxybenzone and sulisobenzone – Penetrate deep into skin and are hormone disruptors.
UVA blockers:
Avobenzone, ecamsule (MexorylTM), Titanium dioxide, Zinc oxide – Safer choices with significantly less of a total health impact.
Note: Zinc oxide has both UVB and UVA blocking properties. It does not absorb into the skin but sits on top and scatters the UV light off the skin. It is now being used in Nano-particle form which reduces the unsightly white residue. It is a skin protectant and anti-irritant and has long been used in diaper rash creams.
Our body requires UVB rays to convert to Vitamin D. Sunscreen use has been speculated as one of the reasons behind the wide-spread Vitamin D deficiency in our population.
Until recently most sunscreens offered the strongest protection against UVB rays and little protection against UVA rays. UVB is the main cause of sunburn.
UVA rays penetrate the skin more deeply, activate free radicals, and are associated with wrinkling, leathering, sagging, and other light damaging effects of aging. UVA rays can also exacerbate the carcinogenic effects of UVB rays. UVA rays are being seen as a cause of skin cancer including melanoma.
Most sunscreens with an SPF of 15 or higher do a great job of protecting against UVB. SPF or Sun Protection Factor is a measure of a sunscreen’s ability to prevent UVB from damaging the skin. Here’s how it works: If it takes 20 minutes for your unprotected skin to start turning red, using an SPF 15 sunscreen theoretically prevents reddening 15 times longer — about five hours.
Another way to look at it is in terms of percentages: SPF 15 filters out approximately 93 percent of all incoming UVB rays. SPF 30 keeps out 97 percent. No sunscreen can block all UV rays.
In 2011 the FDA set the first rules for testing broad spectrum protection, meaning both UVA and UVB. However, more than half of the sunscreens on the US market would not meet the standard that Europe has set for UVA protection. That’s because Europe has asked manufacturers to match the UV blocking potential to the SPF which until now relied solely on UVB. This new standard requires higher blocking of UVA rays.
Choosing a safe sunscreen:
1)Mineral based Sunscreens are the best choice.
2) Lotions are superior to sticks or sprays – You get better coverage with a lotion. The sprays have an inhalation risk and coverage is not uniform.
3) Avoid Oxybenzone and Vitamin A (retinyl palmitate) ingredients.
4) Optimize your Vitamin D level – Having an optimal level of Vitamin D has been shown to be protective against all cancers including skin cancer. For more information on Vitamin D read my blog post here.
5) Practice smart sun: Environmental Working Group offers these smart sun choices before you consider putting on sunscreen. EWG reminds us that we shouldn’t depend solely on sunscreen to prevent sunburn and skin damage.
*Cover up – wear protective clothing including sunglasses
*Find shade or bring your own
*Plan your activities around the sun’s peak hours
When buying a sunscreen Environmental Working Group has done the work for you. Here are the links to their recommended kid’s products and adult products for this season.
ADULTS: http://www.ewg.org/skindeep/ – click on sun for an alphabetical listing of #1 rated sunscreens.
Dr. Purcell,
Glad to know that I have inspired you to write an article. I hope it helps the tribe.
–Wendy