There are many misconceptions about sunscreen! It seems there has been a lot of bad press of late about the safety of sunscreen, and its ability to prevent cancer. I’ve addressed some myths below using the most up to date research from reputable sources.
Sunscreen causes cancer/does not prevent melanoma
False! Older studies found an association between sunscreen use and an increased incidence of melanoma, but association does NOT equal causation. This was likely due to the fact that people who use sunscreen are more likely to be outside with increased sun exposure overall. However, a 2018 study found that 18-40 year olds who were regular users of sunscreen in childhood reduced their risk of developing melanoma by 40%. There is an absolute direct link to sun exposure and skin cancer formation, the more common ones being basal cell and squamous cell cancer.
Sunscreen causes Vitamin D deficiency
False! Sunscreen does block ultraviolet B rays, which are important for generating vitamin D in the skin. However most people apply far less than the recommended amount (one shot glass–sized amount to the body and a teaspoonful to the face), do not cover all sun-exposed skin, or reapply sunscreen regularly. Our skin can likely still synthesize some vitamin D even when it is protected by sunscreen as typically applied. And diet still remains the most important source for Vitamin D.
Sunscreen contains harmful chemicals
True for coral, false for humans. Oxybenzone, a sunscreen chemical also commonly used in many soaps, nail polish, and body fragrances, has been found to be contributing to the bleaching of coral reefs, though many think this is multifactorial (global warming). Considering human toxicity, oxybenzone has not been found to be detrimental in the 60 years that it has been on the market. The Environmental Working Group raised concerns about oxybenzone mimicking hormones in our body, citing a study done in rats. The rats were fed oxybenzone orally, in a dose that would be the equivalent exposure of an individual using sunscreen daily on 100% of their body surface for 277 years. (So therefore not really applicable to typical human use). The FDA is currently requesting more information for studies on humans as well as opening the gates for newer compounds to come to market, which is great for everyone.
Is spray sunscreen safe and effective?
Probably safe, as long as it is used correctly. The problem with aerosol formulas is that much of what you spray is likely getting inhaled, and/or blowing away and landing on your surroundings. We don't know what inhaled sunscreen does to your lungs, but I'm going to vote that it's not great! Recommendations include spraying it into your hand and then rubbing it onto the skin. This will ensure even coverage while limiting the plume created in your wake. Another important fact to keep in mind: a 6oz can of spray is only enough for 6 adult applications. So do not skimp!
There is no reason to use anything higher than SPF 30
True and false. SPF 30 blocks 97% of the sun’s rays; SPF 50 blocks 98%. If you reapply every 2 hours and use the correct amount for your body, SPF 30 is perfectly reasonable. But I advise going with the higher SPF if you are planning an all-day affair at the beach; 1% every day, every summer over a lifetime eventually adds up. Higher SPF does not mean you need to reapply less often, by the way. Also, a new study comparing SPF 50 on one side of the face vs. SPF 100 (99% blocked rays) on the other did show added benefit in protecting the skin from sun damage.
In all, current sunscreen formulations are generally considered safe, and the anti-aging benefits of sun protection are irrefutable. It should continue to be a part of your healthy sun habits for the summer.
Any questions? Feel free to drop me a line at firstname.lastname@example.org.