Myths about sunscreen are widespread. Ensure these misconceptions don’t prevent you from using it to safeguard your skin.
If you’ve ever looked up information about sunscreen online, you might have encountered claims that could make you hesitant to apply these lotions and creams. While sunscreen is intended to shield your skin from the sun’s harmful rays, some claims suggest it might be more harmful than beneficial.
These assertions range from claims that sunscreen is ineffective to warnings that it’s downright dangerous. Some even argue that sunscreen might cause skin cancer due to a supposed mix of toxic ingredients. Such statements can cast a shadow on your day.
But are these claims accurate? We consulted Dr. Jennifer Lin, an assistant professor of dermatology at Harvard Medical School and co-director of the Melanoma Risk and Prevention Clinic at Brigham and Women’s Hospital, to help us distinguish between fact and fiction. Here are her insights into what science truly says about sunscreen and whether it is a friend or foe to your skin.
Here’s a more in-depth look at why sunscreen is essential:
- Prevents Skin Cancer: Sunscreen provides a barrier against the UV rays that significantly contribute to skin cancer, including melanoma.
- Reduces Sunburn Risk: It protects against UVB rays, which cause sunburns and can potentially heighten the risk of skin cancer.
- Guards Against Premature Aging: UV exposure can degrade collagen and elastin, leading to wrinkles, fine lines, and age spots. Sunscreen helps prevent this type of damage.
- Maintains Even Skin Tone: By blocking UV rays, sunscreen helps prevent uneven pigmentation and dark spots caused by sun exposure.
- Improves Skin Texture: Regular use of sunscreen can help improve skin texture, making it appear smoother and more even by protecting against sun damage that causes roughness.
- Reduces Hyperpigmentation: Sunscreen can aid in preventing the development of hyperpigmentation, where dark spots or patches form on the skin.
- Protects Against Pollutants: It acts as a barrier against environmental pollutants and free radicals, reducing oxidative stress and skin damage.
Q: Are there certain chemicals in sunscreen that people should steer clear of? I’ve heard some groups suggest avoiding specific ingredients.
A: Sunscreens fall into two categories: Physical blockers, which reflect the sun’s ultraviolet rays and contain either zinc oxide or titanium dioxide as active ingredients, and chemical blockers, which absorb UV rays and typically include aminobenzoic acid, avobenzone, octisalate, octocrylene, and oxybenzone in the United States.
Oxybenzone has attracted criticism due to concerns it might function as a hormone disruptor—a chemical capable of penetrating cell membranes and potentially interfering with the body’s natural hormone functions.
Nonetheless, there is no definitive evidence proving oxybenzone is harmful to humans. Concerns often cite studies conducted on rats, where oxybenzone was ingested. According to a 2017 study in the Journal of the American Academy of Dermatology, an individual would need to use sunscreen for 277 years to attain the systemic dose equivalent to that in these rat studies. Oxybenzone can also cause allergic reactions in some individuals, though this is relatively uncommon.
Even if you avoid sunscreens containing oxybenzone, it can still be found in other products such as plastics, hairspray, and nail polish. Currently, we are not advising our patients to avoid sunscreens with oxybenzone, but if they choose to do so, they should know this chemical is present in many everyday products.
Q: Some people argue that sunscreen doesn’t protect against the three main types of skin cancer. Is this accurate?
A: No, this is not true. There are robust studies demonstrating that sunscreen effectively protects against the three most common skin cancers: squamous cell carcinoma, basal cell carcinoma, and melanoma. The level of protection sunscreen offers is directly linked to how much ultraviolet radiation contributes to the formation of these skin cancers. For example, prospective studies have shown that sunscreen use can reduce the incidence of squamous cell carcinoma by up to 40% over four years.
Q: An online article suggests that sunscreen is poisoning people. Is this claim valid?
A: There is no credible evidence to support the notion that sunscreen is poisoning us.
Q: Are the nanoparticles in sunscreens containing titanium dioxide and zinc oxide harmful?
A: In physical sun blockers, manufacturers utilize nanoparticles created through a process called micronizing, which breaks down larger particles. This results in sunscreens that apply more smoothly and blend into the skin, unlike the heavier, white sunblocks of the past. These micronized physical blockers are easier to use. Current evidence suggests that nanoparticles do not penetrate beyond the skin’s surface or enter the bloodstream, indicating they are unlikely to pose health risks.
Q: Does everyone need to use sunscreen? Some people say their darker skin that tans well means they don’t need it.
A: We recommend sunscreen for preventing skin cancer, including melanoma, as supported by cohort studies and prospective randomized trials. While darker-skinned individuals have a much lower risk of skin cancer, sunscreen is not strictly necessary for cancer prevention in these cases. However, those wishing to prevent the aging effects of sun exposure would still benefit from sun-protective practices, including the use of sunscreen, sun-protective clothing, and avoiding excessive sun exposure.
Q: Does using sunscreen increase the risk of vitamin D deficiency? Should this be a reason to skip it?
A: Sunscreen does block ultraviolet B rays, which are crucial for producing vitamin D in the skin. However, since most people apply less than the recommended amount (about a shot glass-sized amount for the body and a teaspoon for the face), sunscreen use typically doesn’t lead to vitamin D deficiency. If you’re concerned about potential deficiency, your doctor can suggest a vitamin D supplement, such as 800 IU of vitamin D3 daily. While some experts advise spending 10 to 15 minutes in the sun each day before applying sunscreen, there’s debate about its necessity since vitamin D can be sourced from certain foods and supplements. Worrying about vitamin D levels shouldn’t deter you from using sunscreen.
Q: Do you have any general advice on sunscreen usage?
A: It’s important not to assume that applying sunscreen alone is enough to protect you from sun exposure. Research has shown that people who wear sunscreen may spend more time in the sun, inadvertently increasing their risk of skin cancer. Always combine sunscreen use with other sun protection measures, such as wearing protective clothing and seeking shade.
Sun Safety Tips
To shield your skin from the sun’s harmful rays, consider the following advice:
- Don’t rely solely on sunscreen. The most effective strategy is to minimize sun exposure whenever possible.
- Incorporate sun-protective clothing into your routine, which can be a great complement to using sunscreen and has gained popularity.
- Keep in mind that sunscreen should be reapplied approximately every two hours. The effectiveness of chemical sunscreens diminishes after application, and most sunscreens can be worn off by sweat.
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