Sunscreen 101: Facts you should know to protect your skin

Using out-of-date sunscreen could do more harm than good

JACKSONVILLE, Fla. – We’ve heard it over and over again: "Wear sunscreen when you're outside." 

We know from experts and research that sunscreen can help prevent skin cancer, but which is better: lotion or spray? And does a higher sun protection factor mean more protection? And does a sunscreen's expiration date really matter?

Here's the 101 on sunscreen:

Skin Cancer

One in five Americans will develop some form of skin cancer within their lifetime. 

“That number is actually a little higher for people who live in Florida,” said Katelyn Kelley, a physician’s assistant with Total Dermatology Care Center. 


And this may surprise you: Anyone can get skin cancer, regardless of their skin color.  

“I recommend a yearly skin cancer screening," Kelley said. "More often if you had a skin cancer, or had any atypical moles. The main thing is that you do your monthly self-skin exams."

Kelley recommended remembering the “ABCDEs” of melanoma when performing self-examinations.

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“A stands for asymmetry. A mole should fold in half and be a mirror image of itself," Kelley said. "B stands for borders. They should be nice and even and shouldn't be scalloped or notched. C stands for color. Moles should be uniform in color and not speckled or multicolored. D stands for diameter. The average size of a mole is about the size of a pencil eraser. And E stands for evolving, and that's the most important one. Moles should not change size, shape, color, itch, crust or bleed."

If you find any spots on your skin that don’t look or feel right, you should make an appointment to see a board-certified dermatologist as soon as possible.

But there's even more to skin protection than avoiding cancer.

"While the sun can do great things, like help us produce Vitamin D, it also releases harmful UV radiation," Kelley explained. "UV radiation can cause things like skin cancer. It also can speed up skin aging -- wrinkles, dark spots, etc., are also caused by the sun.” 

Value of SPF

So what's the best way to protect ourselves? Kelley advises people to wear a minimum of SPF 30 every day to protect their skin.

“Face, neck, chest and the back of hands," Kelley said. "We see more skin cancers on the left side of the body. We know that just driving to and from work every day adds up over our lifetime."

SPF 15 blocks about 93 percent of UVB rays, and SPF 30 blocks about 97 percent of UVB rays. But does a higher SPF value mean more protection? 

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“I would say yes, in the amount of protection it provides," Kelley said. "The main thing is proper application technique, so applying enough and reapplying often. I recommend applying 15 minutes before you go outside."

Makeup usually has SPF 15 or SPF 20, which is less protection than doctors recommend.

Many sunscreens on the market claim to be organic, but are those better to use than non-organic?

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“I think of it more in terms of a physical blocker than a chemical blocker. Both are approved by the FDA, although some of the chemical sunscreens are now banned in Hawaii because of the coral reefs,” Kelley said.

Lotion vs. Spray


There are also many varieties of sunscreens available from lotions to sprays. 

Kelley recommends lotion.

“People apply it more evenly. Oftentimes a spray is meant to be rubbed in after it's applied and people don't do that,” Kelley said.

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The Mayo Clinic recommends applying at least one ounce of sunscreen during one application. An easy way to remember that is to think of filling a shot glass.

Remember, sunscreen is not waterproof. It can wash off. Even though it may be water and sweat resistant, it must be reapplied often.

Expiration Date

Regardless of which type or high the SPF is on a sunscreen, users should be cognizant of the expiration date.

According to the Food and Drug Administration, sunscreen typically expires three years after it’s manufactured, but in some instances, it can expire sooner.

“I recommend new sunscreen at least once a year," Kelley said. "And be mindful that expiration date might be sooner than on the package if it's sitting in a hot car. I always recommend sunscreen to be stored at room temperature."

But if you don't have time to run to the store before that trip to the beach, is expired sunscreen better than no sunscreen?

“I would say don't use expired sunscreen," Kelley said. "Expired sunscreen can cause a rash. It's not going to be as effective as regular sunscreen."

So make the time to make sure your supply is up to date and protect yourself.

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