The Truth About Sunscreen

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By News Team on June 15, 2021

You slapped on some sunscreen, now you’re ready to head out into the heat for some summertime fun, right?

Not so fast, says Mark H. Greenawald, M.D., a Family Medicine provider with Carilion Clinic.

“Not all sunscreens are the same when it comes to effectiveness, and not all of us are using it correctly,” he says.

And since it’s estimated that one in five Americans will develop skin cancer in their lifetimes, getting the most protection possible out of sunscreen—in combination with other sun protection measures—is an important step to take as summer starts.

Here’s what you need to know about sunscreen and sun protection:

What To Buy

Broad-spectrum is a must.
“It is vital to note that sun protection factor, or SPF, measures protection against UVB rays, NOT UVA rays,” says Dr. Greenawald.

UVB rays are the main cause of painful sunburns, but both UVA and UVB rays can cause wrinkles and skin cancer. Only broad-spectrum sunscreens provide protection against both types of UV rays.

SPF 30 may not be enough.
This may be especially true given that testing has shown not all products always perform up to their labeled SPF.

There’s no such thing as waterproof sunscreen.
You may see some products labeled as “water-resistant” – but all sunscreens should be reapplied after swimming or sweating.

Mineral sunscreens have tended to perform less well in third-party testing.
This includes sunscreens that contain only titanium dioxide, zinc oxide or both as active ingredients. (An exception: zinc oxide-based sunblock, like the solid white paste lifeguards use on their noses.) 

Expensive doesn’t equal better.
“Consumer Reports testing has repeatedly found that a higher cost and a ‘brand name’ do not necessarily mean that a sunscreen is more effective,” says Dr. Greenawald.
So how to choose the right product? Dr. Greenawald recommends choosing a sunscreen that has performed well in a non-biased evaluation, one that tests all products under the same conditions. This can yield more accurate results than each company testing their own products separately.

How To Use It

There’s a right way to apply it.
Sunscreen should be applied to dry skin 15 minutes before you step outdoors. Don’t forget your feet, neck, ears or the top of your head – or any area of skin that clothing will not cover! This includes your lips, so show them some love and swipe on a lip balm or lipstick that contains sunscreen.

You’re probably not using enough.
According to the American Academy of Dermatology, adults typically need at least one ounce of sunscreen to fully cover their entire bodies. But, most people are only using 25-50% of the recommended amount.  (How much is one ounce, exactly? It’s enough to fill a shot glass.) Don’t skimp! And reapply every two hours, following the directions on the bottle.

You may want to wear it indoors.
Especially if you spend your weekdays working or studying near a sunny window. Glass blocks UVB rays, but some UVA rays can still get through.

It expires.
That bottle that’s been in your bathroom cabinet since your last trip to Florida three years ago? Best to go ahead and toss it.
And lastly but very importantly: No sunscreen blocks 100% of UVA or UVB rays. 
For the very safest fun in the sun, don’t rely on sunscreen alone for sun protection, says Dr. Greenawald.

His suggestions in addition to sunscreen:

  • Wear sun-protective clothing
  • Add sunglasses and hats
  • Make use of umbrellas and other sources of shade
  • Time your outdoor activities outside of the sun’s peak hours, which are from 10 a.m. to 2 p.m.

By covering all your sun protection bases, you can live your best summer life without the sunburn blues.

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