Scroll through social media long enough and you’ll find someone insisting that sunscreen is full of toxic chemicals, that it actually causes cancer, or that humans survived issue-free for thousands of years without it. These claims are everywhere, and while there may be some fact-adjacent basis for them, they are wrong. Dangerously wrong.
At AboutSkin Dermatology and Aesthetics, our Board-Certified Dermatologists treat the consequences of unprotected UV exposure daily, from sun damage and actinic keratoses to aggressive skin cancers that require surgical intervention. Dr. Joel Cohen, who has been named a Castle Connolly Top Doctor 15 times and has been quoted in publications including Vogue, TIME and The New York Times, has made sun protection education a central part of his practice. Dr. Cohen even gave a presentation on sun protection at the New York Stock Exchange before ringing the closing bell.
“The misinformation around sunscreen worries me more than almost anything else I see online about dermatology,” says Dr. Cohen. “We have decades of clinical data showing that daily sunscreen use reduces skin cancer risk. When people stop wearing sunscreen because of a viral post, they’re gambling with their health based on zero evidence.”
Let’s break down the most persistent anti-SPF myths circulating online and look at what the science actually says.
Myth 1: “Sunscreen Causes Cancer”
This is the claim that does the most damage. The argument usually centers on chemical (organic) UV filters like oxybenzone being absorbed into the bloodstream, with critics leaping from “absorbed” to “carcinogenic” without any evidence connecting those two things. What gets lost in the noise is that this concern does not apply to mineral sunscreens. Zinc oxide and titanium dioxide, the active ingredients in physical block mineral sunscreens, are classified by the FDA as generally recognized as safe and effective.
And here’s what’s actually true about chemical sunscreens: an FDA study published in 2020 did find that certain chemical sunscreen ingredients can be detected in blood after application. What the FDA explicitly stated in that same study was that this finding does not mean these ingredients are unsafe. Detectability is not toxicity. The FDA recommended further research, and it did not advise anyone to stop using sunscreen. That said, this is one reason Dr. Cohen recommends mineral sunscreens as the preferred option for daily UV protection.
What we do have conclusive evidence for is the reverse of this myth. UV radiation causes DNA mutations in skin cells, and those mutations cause cancer. According to the Skin Cancer Foundation, regular daily use of SPF 15 or higher sunscreen reduces the risk of developing melanoma by 50 percent and squamous cell carcinoma by about 40 percent. Those numbers come from a well-conducted Australian randomized controlled trial with over a decade of follow-up data, published in peer-reviewed medical journals.
For patients in Denver and the surrounding metro area, this matters even more. Colorado’s high altitude means UV radiation is significantly stronger here than at sea level. As our team has noted in a previous blog on sun protection facts, DNA damage from UVB rays occurs within minutes of exposure, and that damage is amplified at high altitude.
Myth 2: “People Didn’t Wear Sunscreen for Centuries and Were Fine”
This argument ignores a significant detail: they weren’t fine. Skin cancer has existed for as long as humans have been exposed to sunlight. What has changed is our ability to diagnose it, our life expectancy (which gives cancer more time to develop) and our increased recreational sun exposure compared to past generations who covered their skin with clothing for labor and cultural reasons.
One in five Americans will develop skin cancer by age 70, making it the most commonly diagnosed cancer in the United States. Every hour, one American dies from melanoma. These are not statistics that suggest our ancestors had it figured out.
Living in Denver compounds the issue. At 5,280 feet of elevation, residents receive up to 25 percent more UV exposure than those at sea level. Combine that with over 300 days of sunshine per year and an active outdoor culture, and you have a population with above-average sun exposure who need above-average sun protection.
Myth 3: “You Need Unprotected Sun Exposure for Vitamin D”
This myth has a kernel of truth buried under a pile of misapplication. Your skin does synthesize vitamin D when exposed to UVB rays. However, the amount of unprotected exposure needed is minimal, and dermatologists are not telling you to live in a dark room.
Brief, incidental exposure during daily life (walking to your car, running a quick errand) typically provides enough UV contact for vitamin D production, even with sunscreen use. Studies have shown that sunscreen users do not have significantly lower vitamin D levels than non-users in real-world conditions, likely because no one applies sunscreen perfectly or covers every square inch of skin at all times.
For individuals with documented vitamin D deficiency, supplementation is a far safer solution than deliberate unprotected sun exposure. A vitamin D supplement carries no skin cancer risk. Intentional tanning does.
Myth 4: “If Sunscreen Worked, Skin Cancer Rates Wouldn’t Be Rising”
Rising skin cancer rates are frequently cited as “proof” that sunscreen is ineffective. This argument falls apart under even basic scrutiny. Skin cancer diagnoses are increasing in part because detection has improved dramatically. Dermatoscopy, full-body skin checks and greater public awareness all mean we catch cancers today that would have gone undiagnosed in previous decades.
Additionally, many of the skin cancers being diagnosed now reflect cumulative UV damage sustained years or even decades ago, long before broad-spectrum sunscreen was widely available or commonly recommended. Sun damage is cumulative, and only about 23 percent of your lifetime UV exposure occurs before age 18, according to the Skin Cancer Foundation. The damage someone accumulated in the 1970s and 1980s, when tanning oil was more popular than sunscreen, is what we’re treating today.
How to Actually Protect Your Skin
Sunscreen is one part of a complete sun protection strategy. The Board-Certified Dermatologists at AboutSkin Dermatology and Aesthetics recommend the following approach for Denver-area residents and anyone spending time at altitude:
- Apply a broad-spectrum (UVA/UVB) mineral sunscreen with 9% Zinc or higher every morning, even on cloudy days. UV rays penetrate cloud cover and are stronger at high altitudes.
- We recommend physical (mineral) block barrier sunscreens containing zinc oxide or titanium dioxide, particularly after procedures like laser resurfacing, chemical peels or microneedling. These formulations sit on top of the skin and are less likely to cause irritation on sensitive or recently treated skin.
- Reapply sunscreen every two hours when outdoors and immediately after swimming or sweating. A single morning application does not last through an afternoon hike.
- Wear sun-protective clothing with a UPF rating, a wide-brimmed hat and UV-blocking sunglasses. Clothing is actually the most effective barrier against UV radiation.
- Seek shade during peak UV hours, typically 10 a.m. to 4 p.m.
- Schedule annual full-body skin checks with a Board-Certified Dermatologist, and perform monthly self-examinations at home. If something looks suspicious or has changed, don’t wait for your annual visit. Dr. Cohen and the AboutSkin team encourage patients to call for a “spot check” right away for concerning lesions.
Today’s Mineral Sunscreens Aren’t Your Mom’s White Zinc
Dr. Cohen’s published research in the Journal of Drugs in Dermatology has demonstrated that modern mineral sunscreens can be formulated to work well across all Fitzpatrick skin types without the heavy, white-cast drawbacks that once made them less appealing. Many newer mineral formulations now include iron oxides, natural mineral pigments that tint the sunscreen to neutralize the white cast left by zinc oxide and titanium dioxide. Iron oxides also serve a functional purpose beyond aesthetics: they block high-energy visible (HEV) light, also known as blue light, which standard UV filters do not address.
For patients dealing with melasma, which is heavily triggered by UV and visible light exposure, that added layer of HEV protection makes tinted mineral sunscreens especially valuable. You can read more about managing melasma in this detailed guide from our team.
The Bottom Line
Sunscreen is one of the most studied, most validated preventive health tools available to you. And if the online debate about chemical filters has given you pause, mineral sunscreens offer an alternative with an unquestioned safety profile. The anti-SPF movement is built on misread studies, cherry-picked data and social media algorithms that reward outrage over accuracy. No Board-Certified Dermatologist, no oncologist and no public health organization recommends skipping sunscreen. Not one.
If you’ve been on the fence about sunscreen, or if a TikTok video made you second-guess your morning SPF routine, consider this: Dr. Cohen has authored more than 324 medical articles and book chapters, is fellowship-trained in dermatologic surgery and has received the Melanoma Research Foundation Humanitarian of the Year Award. He’s spent his career studying what UV radiation does to human skin. The influencer telling you to skip sunscreen has spent theirs building a following.
Trust the science. Wear the sunscreen.
Your Skin Deserves Better Than a Conspiracy Theory
Confused about which sunscreen is right for you, or overdue for a skin check? The Board-Certified Dermatologists at AboutSkin Dermatology and Aesthetics in Greenwood Village, serving the greater Denver area, are here to help. Call us at 303-756-7546 or book a consultation to get real answers from real experts.
