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UV Safety

Cancer

Exercising Outdoors? Protect Yourself!

There are few things as enjoyable as taking a walk or a jog on a beautiful summer day. It just makes exercising more enjoyable. However, if you’re not wearing sunscreen, your fun summer outing can cause dangerous—and possibly even fatal—damage to your skin.

It’s easy to take our skin for granted. It’s washable, flexible and durable. It regenerates itself when we get a cut or scrape, and it doesn’t seem to require a lot of maintenance. Yet we often forget that skin is the largest organ of the body, protecting our internal workings from disease and trauma all day, every day. But skin that is overexposed to the sun begins to break down, losing its ability to protect us and becoming more vulnerable to disease.

For that reason, before you step out the door—every time, without exception—it is critical that you apply a generous layer of high-quality sunscreen. Remember that SPF (sun protection factor) ratings refer only to protection from the effects of UVB rays. It’s important to check sunscreen labels to ensure that the product is a broad-spectrum sunscreen, protecting you not only from UVB but from UVA radiation also.

Products containing zinc oxide or titanium dioxide are among those that provide protection against both UVA and UVB. The American Academy of Dermatology recommends using a water-resistant, broad-spectrum sunscreen with SPF of at least 30.

The 411 on SPF

SPF ratings are based on how much longer you may be protected from sunburn than if you weren’t wearing sun protection. For instance, if you normally burn in 20 minutes, a product with SPF 30 will enable you to stay in the sun 30 times longer—so you should be able to stay in the sun without burning for 10 hours, assuming you apply the sunscreen properly and reapply it after swimming, heavy sweating, toweling off or other activities that remove the product from your skin.

“It is very important to understand that the SPF number doesn’t refer to a sunscreen’s strength,” said Alfred Yu, MD, medical director of Simi Valley Hospital’s Emergency Department. “For example, an SPF 30 is no stronger than an SPF 8. It doesn't filter out more harmful rays than an SPF 8, but it does protect you longer.”

Early and Often

Most people use sunscreens too sparingly. Labels of most sunscreens call for liberal and frequent applications. A liberal application is 1 ounce—two tablespoons—to cover all exposed parts of the body.

Timing is important, too. To have the best effect, sunscreens need to be applied 30 minutes before you start your activity. Because of sweating, swimming and toweling off, sunscreen should be reapplied throughout the day. Even water-resistant sunscreens need to be reapplied every 90 minutes.

“It is extremely important for parents and other caregivers to take responsibility for reapplying sunscreen to their children throughout the day when they’re swimming or playing,” Dr. Yu advised. “Kids get wrapped up in their activities—even older children who may seem capable of remembering these kinds of things. It’s up to parents and caregivers to monitor their activity and make sure they’re staying protected.”

An Important Change

Starting last year, a mandate from the federal Food and Drug Administration requires sunscreen labels to disclose not only the product’s SPF, but also whether or not it meets federal standards of protection against skin cancer.

In order to make a skin cancer protection claim, the product must offer broad-spectrum UVA and UVB protection and an SPF of 15 or higher. Otherwise, the label must clearly state “This product has been shown only to help prevent sunburn, not skin cancer or early skin aging.”

“This is a really helpful change, and one that can literally save people’s lives,” Dr. Yu said. “Of course we want to spare people the pain of a sunburn, but what’s really crucial is their protection against skin cancer. For that reason, it’s important for consumers to carefully read their sunscreen label to make sure it provides at least the minimum protection against skin cancer.”