Debunking myths, misconceptions and misinformation about sunscreens: no evidence they cause cancer, but they do expire

Myth 1: All sunscreens work the same way.
False. Sunscreens can prevent sunburn in different ways:

• Chemical sunscreens: The active ingredients in chemical sunscreens absorb ultraviolet (UV) rays as they hit the skin, Patel explains.
• Physical blocker sunscreens: Physical sunscreens, which are also called mineral sunscreens or sun blocks, use ingredients such as zinc oxide and titanium dioxide to form a barrier on the skin’s surface that reflects UV rays.

Not sure whether to use a chemical or physical sunscreen? Hybrid sunscreens contain both chemical absorbers and physical blockers.

When selecting a sunscreen, Anderson dermatologists recommend choosing a broad-spectrum product with at least sun protection factor (SPF) 30. ‘Broad spectrum’ means the product protects from both UVA and UVB rays which can lead to sun damage and skin cancer. SPF refers to the amount of UVB rays it blocks.

Myth 2: It doesn’t matter what kind of sunscreen I choose.
False. While wearing sunscreen is always a good choice, each type of sunscreen has instructions that must be followed to ensure your skin is protected.

Sunscreen comes in formats including cream, lotion, spray, powder and stick.

Each type of sunscreen has benefits and limitations. For example, many spray sunscreens are clear and absorb into the skin quickly, but this feature can make it challenging to see if you’ve missed a spot.

Overwhelmed by options? Anderson dermatologists recommend physical blocker sunscreens. Patel says this is because they have the broadest range of UVA and UVB protection.

Whatever type of sunscreen you choose, always review its instructions for information on how – and how frequently – to apply and reapply.

Myth 3: Sunscreen causes cancer.
False. There is no medical evidence that sunscreen causes cancer. However, there is a lot of evidence that UV rays from the sun and tanning beds do.

In the past, some sunscreens were recalled for being contaminated with a chemical called benzene. Benzene is not normally found in sunscreen. This recall doesn’t mean you should stop wearing sunscreen, dermatologists say.

Still, some may feel more comfortable using sunscreens that don’t absorb into the skin – that is, those physical blockers sunscreens described above.

Additionally, sunscreen isn’t the only way you can practice sun safety. “There are a lot of sun protective options outside of just the creams and sprays,” Patel says.

Other ways to protect yourself from sun damage include:

• Wearing protective clothing that is dark and tightly woven, with ultraviolet protection factor (UPF) 50+
• Wearing a wide-brimmed hat
• Wearing sunglasses with UVA and UVB protection
• Seeking shade between 10 a.m. and 4 p.m. when sun rays are strongest

Myth 4: I have dark skin. I don’t need to wear sunscreen.
False. Dark skin is susceptible to sun damage.

It takes more sun exposure for darker skin types to get sun damage, Patel says. She explains this is because melanin, which gives skin its color, provides DNA with a small amount of sun protection. Still, this small amount of protection doesn’t prevent sun damage altogether.

“Darker-skinned people can still get a sunburn, still get skin cancers and definitely still get photoaging from UV exposure,” Patel says.

Regardless of your skin color, apply sunscreen liberally 30 minutes before going out in the sun, and don’t forget to reapply every two hours or after swimming or sweating.

Myth 5: My sunscreen is waterproof, so I don’t need to reapply it after swimming or sweating.
False. According to the Food and Drug Administration, there is no such thing as waterproof sunscreen.

There is, however, water-resistant sunscreen. The FDA says these products offer water-resistant sun protection according to the time and SPF level specified on each product.

Heading for a beach day or outdoor workout? Choose a water-resistant sunscreen and follow the product instructions on how often to reapply.

Myth 6: My sunscreen is SPF 50, so I don’t need to apply it as often.
False. No matter the SPF number, chemical absorber sunscreens only work for about two hours and should be reapplied after swimming or sweating.

Regardless of the SPF level you choose, you need to reapply with the same frequency, Patel says.

If you have trouble remembering to reapply, Patel suggests using a physical blocker sunscreen. These products don’t rub in or disappear into the skin, so it is easy to determine when to reapply.

“If you can see the white on your face, it’s still working,” she says.

Myth 7: There is SPF in my makeup. I don’t need to wear sunscreen.
False. While Patel says that sunscreen in makeup counts, it usually doesn’t provide the recommended SPF levels.

“It’s typically only 5 to 15 SPF, and we recommend 30,” she says.

Check that your makeup offers at least 30 SPF, and supplement with additional sunscreen as needed. Finally, don’t forget to apply sunscreen to other exposed areas of your body, and make sure you reapply sunscreen as directed throughout the day.

Myth 8: I only need sunscreen when it is sunny.
False. Sunburn and sun damage may be associated with hot, sunny weather, but they can also occur in cold, cloudy conditions.

“Even when it’s cold, sun is getting through the clouds,” Patel says.

While clouds filter some UVB rays, they don’t block UVA rays which are a risk factor for melanoma, she adds.

So even if it’s cloudy or cold, you need to apply your sunscreen the same way you would if it were a warm sunny day.

Myth 9: Sunscreen doesn’t expire.
False. “You cannot rely on expired sunscreen,” Patel says. “Nothing bad is going to happen if you use an expired one in terms of increased toxicity. It just won’t work.”

It is also important to store sunscreen properly. Specific storage instructions can be found in the product’s ‘Drug Facts’ section.

For example, if you store your sunscreen in a hot car or in direct sunlight, Patel says the product could degrade earlier than its expiration date.

“You have to look at the storage recommendations. Sunscreen will only last until the expiration date if you keep it within those temperature ranges,” she says. “If you go outside of those temperature ranges, the molecules that are protecting your skin will degrade faster.”