Depending on how you’re using it, the answer might surprise you.

Sunscreen can help reduce your risk of skin cancer, which, according to the American Cancer Society, is the most commonly diagnosed form of cancer in the United States. Although, if you don’t apply your favorite product correctly, your sunscreen may not work as well as it could.

This summer, take these five steps to make sure your sunscreen is doing its job:

1. Measure it out. You may have heard the advice to use a shot glass full of sunscreen — about 1 ounce — to cover your entire body. But it might be easier to think smaller. One way to apply enough, according to the American Academy of Dermatology (AAD), is to rub one teaspoon of sunscreen onto your face and scalp, one onto each arm, two onto your stomach and back, and two onto each leg.
2. Spray generously. Spray sunscreens are certainly convenient. However, the AAD warns that with sprays, it can be hard to see how much you’re actually putting on, which could result in inadequate coverage. If you prefer sprays, apply enough so you can see an even sheen on your skin, and always rub it in.
3. Store wisely. If you’re outdoors in the heat, the U.S. Food and Drug Administration (FDA) recommends wrapping your sunscreen bottles in a towel or even storing them in a cooler, as these products shouldn’t be left out in the sun or heat. Also, don’t leave bottles in your car for a prolonged period of time. If you notice a product has changed color or consistency, toss it out, advises the AAD.
4. Rely on SPF — but not entirely. A sunscreen’s sun protection factor (SPF) relates only to how well it protects against the UVB rays that cause sunburn, according to the FDA. However, UVA rays cause aging, and both UVA and UVB rays can cause skin cancer. SPFs are important, and the AAD recommends using at least an SPF 30. For full protection against UV damage, however, make sure your product is labeled “broad spectrum,” which means it has been tested to protect against both UVA and UVB rays, advises the FDA.
5. Reapply at least every two hours, no matter the SPF. The AAD conducted a survey in 2016 and found that a majority of those polled incorrectly believe that high-SPF sunscreens protect them for longer than low-SPF sunscreens. SPF has nothing to do with the length of time you can spend in the sun. It actually defines how much UVB radiation gets blocked, according to the FDA. No sunscreen lasts all day. Always reapply products every two hours or after swimming or sweating heavily.

When in doubt, stay inside! The sun is strongest in the middle of the day, and staying indoors between 10 a.m. and 4 p.m. can help you both avoid a burn and reduce your cancer risk from overexposure to UV radiation, advises the American Cancer Society.

Concerned about your risk for skin cancer? Your primary care provider can give you advice and do basic skin checks. Don’t have a doctor? Tennova Medical Group is here to help. Our family practice office located on Tiny Town Road welcomes new patients of all ages. Call 931-502-2423 or visit TennovaMedicalGroup.com. Ask about our same- and next-day appointments.

For more health and wellness articles like this one, visit our blog at TennovaWellness.com

This publication in no way seeks to diagnose or treat illness or to serve as a substitute for professional medical care.