Sunscreen use is heavily promoted on TikTok, but the relatively uncommon posts containing misinformation attract high audience engagement, researchers reported.

“Contrary to claims that TikTok is rife with sunscreen misinformation, our findings indicate that such content constitutes a small portion of the most viewed videos,” Alessandro Marcon, PhD, research associate at the Health Law Institute of the University of Alberta in Edmonton, and colleagues wrote. “However, these critique-focused TikToks, despite being few, consistently generated significantly more audience interaction. This suggests that critical or contrarian content may attract disproportionate attention even when not widely represented.”

Among 971 of the most-viewed sunscreen-related TikTok videos, close to 87% promoted sunscreen use, whereas 6% contained critiques framed around health harms or the idea that sunscreen blocks the benefits of sun exposure. Those negative videos generated significantly higher mean likes, shares, and comments than videos promoting sunscreen use.

“Growing trends show that misinformation is often shared by a smallish number of prominent accounts, and that this content often leads to viral spreads,” Marcon told Medscape News Canada. Nevertheless, he added, “It’s positive to see such a high percentage of videos promoting sunscreen!”

The study was published online on June 18 in PLOS Digital Health.

Use Tied to Skin Care, Not Cancer

The researchers conducted an iterative search of TikTok in September and October 2024 to identify the most common sunscreen-related hashtags on the platform. The following five hashtags accounting for 76% of all sunscreen-related posts were selected for data collection: #sunscreen, #sunscreenviral, #spf, #sunscreenreview, and #sunprotection. The posts had amassed more than 2.4 billion views, 94.8 million likes, 3.3 million shares, and 728,000 comments.

After an analysis of the most downloaded posts, the researchers included 971 videos in their final dataset. Videos were classified as sunscreen promotion or broad or product-specific critique, and audience engagement was assessed. Sunscreen misinformation was defined as content suggesting that sunscreen is harmful to health or that it unnecessarily blocks benefits of sun exposure, such as vitamin D absorption.

Most videos promoted sunscreen use (86.8%), typically to prevent skin damage (17.4%), acne (15.3%), aging (11.5%), and cancer (6.1%).

A total of 58 videos (6%) raised health-related concerns about sunscreen, with 15 videos (1.5%) asserting that sunscreen causes harm and 12 (1.2%) claiming that it prevents health benefits. Examples of these health-related critiques included claims that sunscreen ingredients act as hormone disruptors, contain carcinogens, taint breast milk, or introduce harmful microplastics into the body.

Videos also criticized specific products on non-health grounds. The most common criticisms were that sunscreen left a white cast on the skin (5.6% of all videos), felt greasy or oily (2.8%), or irritated the skin (3.2%).

Overall, critical videos generated more engagement than promotion-only videos. Mean likes for criticism-only videos were roughly double those of promotion-only videos (193,746 vs 96,712), and mean shares and comments were three to four times higher.

Sunscreen content was often woven in with broader skincare and product marketing. Specific sunscreen products were featured in 68.2% of videos, and 61.7% promoted particular products, in some cases with discount codes.

Dermatologists appeared on camera in about 8% of videos and were mentioned by others in an additional 1.3%, putting dermatologist presence at roughly 10% of the sample overall. Only 6.1% of videos explicitly mentioned reducing cancer risk as a reason to use sunscreen.

“Cancer is seldom explicitly mentioned, but perhaps that message is implied and understood by audiences,” Marcon said. “If messaging focuses more on beauty and aesthetics but still reaches that goal, it can’t really be seen as a bad outcome.”

Critiques Prioritized by Algorithms

Samiha Mohsen, MD, a dermatology resident at the University of Calgary, told Medscape News Canada that the findings must be placed in context. Because the researchers analyzed the most-viewed videos under specific hashtags, the results reflect trending content rather than what any individual TikTok user sees in his or her personalized feed.

“The trends I see on TikTok are biased by an algorithm that will put forward whatever has increased watch time or engagement, or things I’ve shown previous interest in,” Mohsen said. “The more you believe a concept like sunscreen is harmful, the more you will see people posting about the harms of sunscreen.”

The low proportion of videos mentioning cancer risk may not represent a cancer risk messaging failure, said Mohsen, noting that only about 10% of the videos featured dermatologists. “We can’t expect the public to provide general recommendations that are rooted in medicine,” Mohsen said. “I don’t think it’s wrong for people to promote sunscreen and skin cancer awareness, but to expect that of content creators is unreasonable.” She added that dermatology associations are increasingly running their own TikTok and Instagram campaigns aimed at younger audiences to help fill the gap.

For clinicians counseling patients, Mohsen recommended pointing to guidance from professional societies such as the Canadian Dermatology Association or the American Academy of Dermatology, both of which recommend a minimum sun protection factor of 30 with reapplication every 2 hours, and referral to a dermatologist for those, such as immunocompromised patients, who are at higher risk.

Suzanne Sirota Rozenberg, DO, chief of dermatology at Episcopal Health Services in Far Rockaway, New York, told Medscape News Canada that the findings are consistent with patterns she has observed with other health topics on social media. Like Mohsen, she noted that “while most content is favorable, negative reels are often prioritized by algorithms, causing them to appear more frequently and shift the overall messaging.”

Negative content often gains traction and likes quickly because of its shock value, despite lacking scientific evidence, she affirmed.

The low emphasis on cancer risk in sunscreen content likely reflects what motivates younger audiences, Rozenberg said. “Skin cancer often feels like a distant concern for younger TikTok viewers. Focusing on the immediate cosmetic benefits of sun protection provides quicker gratification and is a more effective way to reach this demographic.”

In her own practice, discussing future cancer risk is less persuasive than pointing to the immediate, visible effects of sun damage, such as wrinkles or asymmetric photoaging. “We must continue to reinforce that pale is beautiful and that tanning is harmful, especially as many teens now routinely track the UV index specifically to seek sun exposure,” she said.

Rozenberg’s take-home message for clinicians is to counter online misinformation directly with patients. “Clinicians should remind patients that clickbait does not equal truth and is not science-based,” she said. “It is important to emphasize that the proper application of sunscreen, 2 ounces every 2 hours, still allows for vitamin D production and some color.”

She added that while skin cancer risk may feel remote to younger patients, “it is a significant future risk if they continue to tan, and sun exposure directly accelerates the aging process.”

The study received funding support from the Canadian Cancer Society Challenge Grant. Marcon and Mohsen declared no relevant financial relationships. Rozenberg declared being part of a speakers bureau for Galderma and a speaker for Aerolase, Cutera, Cartessa Aesthetics, and Jeisys. 

Marilynn Larkin, MA, is an award-winning medical writer and editor based in New York City whose work has appeared in numerous publications, including Medscape Medical News and its sister publication MDedge, The Lancet (where she was a contributing editor), and Reuters Health.