Sunscreen SPF Ratings are Misleading: How to Choose Your Sun Protection

First Posted: May 20, 2013 12:05 PM EDT

Spring is rapidly giving way to summer as children finish up classes and college graduates start their new jobs. As people hit the beach and the outdoors, though, the sun will be brighter than ever-and you should keep some very specific tips in mind when choosing your sunscreen.

There are many issues associated with sunscreen. Bottles often carry SPF ratings that are misleading and potentially dangerous for consumers. In fact, a survey of 1,400 sunscreen products by the Environmental Working Group found that while most products meet new federal requirements put in place last December, they still have the potential to confuse consumers, according to Fox 21 News.

The new guidelines from the Food and Drug Administration ban terms such as "waterproof," since all sunscreens will wash off over time. In addition, they require that sunscreens filter out both A and B rays. In the past, some sunscreens only protected against UVB rays (the type of ultraviolet light that causes burns) and not UVA rays (the type that causes DNA damage and ages the skin. Both types of ultraviolet light can cause cancer, according to Medical Daily.

While these new guidelines do help with some confusion, there are still issues with SPF ratings. Any sunscreens with SPF ratings above 50 have long been viewed with skepticism by experts. That's mainly due to the fact that ratings of 100 or 150 often give a false sense of security to consumers and often lead them to stay in the sun long after the lotion has worn off.

In fact, SPF doesn't actually relate to protection increases. It actually indicates the amount of sun exposure needed to cause sunburn on sunscreen-protected skin compared with unprotected skin. A SPF rating of 30 means it would take 30 times longer for a person to receive a burn. In addition, sunscreen with SPF 100 only increases protection from UVB by one percent (from 98 to 99 percent) when compared to sunscreen with SPF 50.

"The challenge is that beyond 50 the increase in UV protection is relatively small," said Henry Lim, chair of dermatology at the Henry Ford Hospital in Detroit, in an interview with Fox 21 News.

Currently, the FDA is reviewing SPF ratings on sunscreens. Whether or not they'll decide on placing a cap on what can be labeled, though, is another question entirely.

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