Do Sunscreens Prevent Skin Damage?

Most people who go out into the sun wearing sunscreen and don’t get a sunburn probably think their skin was adequately protected.

This is often far from the truth. Here’s why.

People pick sunscreen based on the SPF value, and falsely assume that preventing sunburn means they have protected their skin from UV damage. This is not the case. Many sunscreens don’t provide adequate protection from UVA rays. While higher-energy UVB rays are the primary cause of sunburns and pre-cancerous DNA mutations, lower-energy UVA rays cause more subtle damage. They penetrate deeper into skin tissue and are most responsible for generating free radicals – energized molecules that are highly reactive and can damage DNA and skin cells (Marrot 2005), promote skin aging (Wlasckek 2001) and cause skin cancer.

Sunscreens should be carefully formulated and tested to ensure they offer the strongest and most lasting protection from the UVA-related skin damage including free radicals and immune system suppression. Currently, results vary from product to product. The sunscreens with the best UVA protection are best at suppressing free radical formation, but many American sunscreens are lacking in UVA filtering.

UV rays quickly break down avobenzone, the most common UVA filter in American sunscreens, unless it is mixed with a stabilizer. Zinc oxide is the only other approved ingredient with strong UVA filtering, and titanium dioxide is moderately effective in the UVA spectrum.

One study found that when someone used the recommended amount of sunscreen, free radical generation dropped by 55 percent, but there was less benefit when a thinner coating of sunscreen was applied (Haywood 2003). Other studies found sunscreen reduced free radicals by 50 to 75 percent, which is far less than the 95 to 99.9 percent reduction in sunburn risk (Haywood 2012).

European sunscreens appear to provide greater free radical protection because they can contain superior UVA filters. In tests, 12 European sunscreens averaged a free radical protection factor of 13, and the two most similar to U.S. products offered much less UVA and free radical protection (Wang 2011).

Many of the sunscreens currently on the market also contain anti-inflammatory and antioxidant chemicals that can boost the SPF value. But unlike a FDA-approved active ingredient in sunscreen, they do not prevent UV rays from hitting the living skin cells (Kobo 2015). Anti-inflammatories reduce skin reddening, but it is unclear if they are as effective at preventing other UV-related skin damages. Antioxidants are added to absorb or “quench” the free radicals caused by UV rays. Given their increasingly widespread use, EWG urges the FDA to prioritize the study of these SPF boosters and determine whether they offer protection from other, long term skin damages.

To be truly effective at preventing skin damage and skin cancers, U.S. sunscreens need to provide better protection from UVA. This will not happen until the FDA sets higher requirements for UVA protection and approves modern sunscreen ingredients with superior UVA filtering and stability. Instead FDA’s weak regulations allow nearly every sunscreen to claim “broad spectrum,” or UVA, protection, even though some are much better than others. Sunscreens that fail the test can still be sold. These weak rules give manufacturers little incentive to improve their products.

In the absence of truly protective regulations, consumers are in the worst possible position: they are likely to think that their sunscreen is providing more protection than it really is, so they stay out longer in the sun and increase their risk of skin cancer and skin damage.


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About the ratings

EWG provides information on sunscreen products from the published scientific literature, to supplement incomplete data available from companies and the government. The ratings indicate both efficacy and the relative level of concern posed by exposure to the ingredients in this product - not the product itself - compared to other sunscreens. The ratings reflect potential health hazards but do not account for the level of exposure or individual susceptibility, factors which determine actual health risks, if any. Methodology | Privacy Policy | Terms & Conditions

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