Sunscreen Facts and Myths You Need to Know About

With so much misinformation out there, we're setting the record straight with help from skincare experts.


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You know sunscreen is the one product that should be in your skincare routine year-round. Your mom, dermatologist, and favorite beauty editors have reminded you time and time again that wearing SPF is crucial when it comes to preventing not only the signs of aging but also skin cancer — whether you're at the beach or sitting indoors. But with all of the confusing and conflicting information about sunscreen and skin cancer, it becomes nearly impossible to separate sunscreen facts from myths. That's why we reached out to skincare experts to set the record straight and bust seven of the most common sunscreen myths out there.

Keep reading for sunscreen facts and myths you need to know about, according to top dermatologists.

The Facts

According to the American Cancer Society, melanoma, the most dangerous form of skin cancer, will affect nearly 100,000 people in the United States in 2023, and almost 8,000 people will die from it. While that statistic is scary, it's not absolute. Sunscreen can play a major role in decreasing your risk of developing melanoma and other types of skin cancer — that is, if you're using the right SPF and applying it properly. However, many have trepidations when it comes to the ingredients used in sunscreen formulas.

The Environmental Working Group's 14th annual Guide to Sunscreen study revealed that researchers rating the safety and efficiency of over 1,300 SPF products, including sunscreens, lip balms, and moisturizers, found that only 25% of these products provided adequate protection and did not contain controversial ingredients like oxybenzone.

In 2020, two studies by the FDA found that oxybenzone, along with five other common active ingredients in chemical sunscreens have been proven to absorb into the skin and potentially cause harm. However, the FDA stresses that more studies need to be done to deem these ingredients unsafe, and that "absorption doesn't equal risk."

The Myths

Myth #1: The higher the SPF, the better protection

The answer is not that simple. SPF measures protection against ultraviolet B rays (UVB), which are known for causing sunburns in the summer, but UVA rays can also cause skin damage.

"There is a curve of diminishing returns when it comes to SPF and the percentage of UV protection," says Dr. Melanie Palm, board-certified dermatologist and founder of Art of Skin MD. "An SPF of 2 provides about 50% protection, SPF 15 - 93%, SPF 30 - 97%, SPF 50 - 98%, and SPF 100 – 99%. Therefore, an SPF of 30 or more provides excellent UV protection and ridiculously high SPF numbers are not really necessary to provide UVB protection. 100% UV protection is not really possible through commercially available sunscreen formulations."

The FDA also found that high SPFs don't necessarily offer the same level of ultraviolet A ray (UVA) protection. However, overexposure to UVA rays can increase the risk of skin cancer and signs of aging. So if you only have SPF 100 in your medicine cabinet, you should still wear it.

Myth #2: Wearing sunscreen is enough to protect you

Yes, sunscreen will greatly reduce the risks of skin cancer, but how you apply it is equally important.

"In order for SPF to be effective you need to apply the correct amount, which is about a teaspoon for each limb and a teaspoon for the face," explains Dr. Marina Peredo, board-certified dermatologist and founder of Skinfluence. "You should also take other sun protection precautions like wearing a wide-brimmed hat, sunglasses, and staying in shadier areas."

For the best protection, Dr. Peredo recommends applying sunscreen 30 minutes before you go into the sun and reapplying every two hours. "If you apply sunblock incorrectly you could reduce your SPF 30 to SPF 7, which will not protect you from the harmful rays," she adds.

Myth #3: You don't need to wear sunscreen indoors or on cloudy days

This is where finding a sunscreen product that shields skin from UVA and UVB rays comes into play. UVA rays have longer wavelengths and can damage skin regardless of the weather or the fact that you're sitting by your living room window.

"There are different types of ultraviolet rays that affect the skin,” says Dr. Elizabeth Hale, board-certified dermatologist and senior vice president of The Skin Cancer Foundation. “We mostly talk about ultraviolet A (UVA) and ultraviolet B (UVB) rays. People classically think about UVB rays because they are what cause sunburns in the summertime. In reality, UVA rays are what cause sun damage regardless of the season of the weather because they have longer wavelengths that penetrate through clouds. By similar logic, UVA rays also penetrate through windows."

Myth #4: Physical sunscreens are better than chemical ones

While the FDA has found that six common active ingredients in chemical sunscreens absorb into the skin, the government has stressed that further studies need to be made to rule them unsafe. However, physical sunscreens are less likely to cause irritation.

"Physical sunscreens, zinc oxide and titanium dioxide, are minerals and are incapable of causing a skin reaction," Dr. Palm explains. "Physical sunscreens work by reflecting light back into the environment, like a mirror. By contrast, chemical sunscreens convert light energy into heat on the surface of the skin." The heat can cause inflammation, leading to the formation of abnormal pigmentation on the skin.

Another benefit of physical sunscreens is that they also block non-UV light such as blue and infrared. They also don't absorb into the skin. "It has been scientifically proven that nanoparticle physical sunscreens are not absorbed systemically, whereas chemical sunscreens have been shown to be absorbed systemically as shown in blood draws following skin application," Dr. Palm says.

The caveat? Chemical sunscreens are easier to wear under makeup since they blend seamlessly into the full tonal spectrum of skin. And while there have been improvements in physical formulas, many still leave behind white casts.

Myth #5: Moles won't become cancerous if they don't get a lot of sun exposure

The short answer: Absolutely false! Actress and EltaMD ambassador Michelle Monaghan has had firsthand experience with skin cancer. She was able to detect her cancer early, after her husband, Peter White, noticed a mole on the back of her leg.

"We had been together for five years at that point and he noticed a suspicious mole on my calf. He told me over the course of several months that I should go and get that checked out because it could be skin cancer," she tells InStyle. "Even though my dermatologist said that she thought the mole was fine, she removed it and biopsied it just to be sure. I got the biopsy back and it was melanoma, but fortunately, I listened to my husband and caught it at an early stage."

According to Dr. Peredo, all moles — and not just those exposed to the sun — can potentially become cancerous. "Some people are born with a genetic predisposition to melanoma and for those people, moles that do not receive direct sunlight can turn cancerous through other triggers such as their immune system or their genes," she says. "Some people are born with dysplastic nevi, or irregularly shaped moles, and these can become cancerous and are harder to notice if they change shape, color, or size."

Hence, why it's so important to see your dermatologist for an annual skin check. And if you notice an irregular mole but can't get immediate medical attention, document it. For Monaghan, her husband was her monitor system. "I think that it's important that if you have a suspicious mole and you have someone close enough in your family, take a picture of it, look at it, and pay attention to how it changes," she says. "If you can't get to a doctor right away, if it changes its appearance over the course of a few months, it could be your indicator of what to do next."

Myth #6: Dark skin tones can't get skin cancer

If you have skin, you can get skin cancer. Period. However, it can manifest differently in certain skin tones. "Some skin types have disproportionate distributions of locations of melanoma," says Dr. Palm. "For example, Black skin is more likely to develop acral melanoma (on the palms or soles) than the general population." In fact, Dr. Palm shares that 21 of her new melanoma diagnoses in the past year were in darker skin tones.

"Darker skin won’t burn as easily, but that doesn’t mean that the damaging effects of UV rays in the form of hyperpigmentation, wrinkles, and cancer aren’t occurring," Dr. Chaneve Jeanniton, oculofacial plastic surgeon and founder of Brooklyn Face and Eye previously told InStyle.

VIDEO: When You Apply Sunscreen in Your Routine Actually Matters A Lot

Myth #7: Getting a base tan will make you less prone to sunburns and skin damage

Maybe part of your pre-prom routine included going to the tanning salon or you and your college friend went together ahead of your spring break vacation. Either way, you've probably heard about the base tan myth. As a skin cancer survivor, Monaghan now sees why base tans are flawed.

"I grew up in the years where, when it was prom, all of the local girls would go to the tanning salon to get a tan for their prom dresses," she says. "Never in a million years would I do that now, and I don’t think I would have done that then if I had the information and the education about the implications of what sun exposure and damage can ultimately lead to. That’s why I think it’s so very important to have open conversations about skin cancer."

And just to set the record straight: "The idea of a base tan is a fallacy," says Dr. Palm. "A tan is an indication of DNA damage within the skin. Enjoy the skin you are in and avoid unneeded UV exposure."

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