Burning Lies: The Dangerous Spread of Sunscreen Misinformation Online

By Douglas Hassell, Northeastern University

In today's fast-paced social media landscape, misinformation spreads rapidly, and a particularly harmful wave of sunscreen misinformation has emerged. While humor and aesthetic posts dominate social media feeds, misleading claims about the safety and efficacy of sunscreen are gaining traction, casting doubt on an essential tool for skin protection. Self-proclaimed health experts and social media wellness influencers attract millions of views discussing the glowing benefits of sun exposure while doubting the risk of skin cancer and the need for sunscreen—all without any citation or credentials. For context, in the United States, 1 in 5 Americans will develop skin cancer by age 70, and over 85% of skin cancers are caused by exposure to the sun's ultraviolet (UV) radiation. The combination of social media algorithms and dramatic misinformed claims about the potential harm of sunscreen creates a dangerous trend that leads to real-world consequences, undermining public health efforts and increasing the likelihood of skin damage among vulnerable populations.

The Rise of Sunscreen Skepticism

In the past year, there has been a disturbing rise in sunscreen fear-mongering on social media. Numerous online influencers have inaccurately proclaimed that constant sun exposure is healthy and that sunscreen is the cause of skin cancer. Platforms like TikTok are inundated with misinformed claims against sunscreen, often downplaying the serious risk of skin cancer. Even high-profile celebrities have taken to social media to voice their opinions. TV personality Kristian Cavallari stated on her podcast, Let's Be Honest, that she does not use sunscreen and questioned the validity of its importance. Furthermore, Dr. Andrew Huberman, a neuroscientist and podcast host, stated on his podcast Huberman Lab, “I'm as scared of sunscreen as I am of melanoma.” Such statements can lead to confusion and distrust in scientifically supported sunscreen guidelines, making it more difficult for individuals to make informed choices about sun protection and increasing the potential for skin damage in the long run.

Simultaneously, with the rise of online sunscreen misinformation, there has also been a piqued interest in DIY sunscreen recipes. One notable example involves online influencer and model Nara Smith, who posted a TikTok video creating a homemade SPF recipe with her husband, Lucky Blue Smith, amassing 21.5 million views and two million likes. In the one-minute video, Mr. Smith combines coconut oil, beeswax, shea butter, cocoa butter, jojoba oil, and zinc oxide powder in a process reminiscent of crafting a baking recipe. While this captivating video may seem harmless, it is a symptom of a larger problem: a lack of trust and understanding in modern sunscreen formulations. Furthermore, after only a quick search online, dozens of 'DIY' or 'at-home' sunscreen recipes populate the search. Often, many promote ineffective SPF materials such as coconut or castor oil, and the recipes that contain zinc oxide (the active ingredient in mineral sunscreens) are not formulated correctly to have adequate sun protection. This trend has become so pervasive that the American Academy of Dermatology issued a warning stating that homemade sunscreens are ineffective and may leave users vulnerable to skin cancer. Viewers may turn to DIY sunscreen in an effort to find a 'cleaner' alternative to available consumer sunscreens; however, DIY sunscreens do not provide proper SPF protection and give consumers a false sense of protection.

The increasing skepticism surrounding sunscreen is reflected in recent research that reveals troubling trends among young adults. An online survey by the American Academy of Dermatology found that 28 percent of respondents aged 18 to 26 do not believe suntans can lead to skin cancer, and 37 percent only wear sunscreen when prompted by others. Additionally, an Orlando Health Cancer Institute poll revealed that 14 percent of adults under 35 believe daily sunscreen use is more harmful than direct sun exposure. This disconnect underscores the detrimental impact of misinformation, as young individuals may be more susceptible to misleading narratives shown by social media influencers, ultimately leading to dangerous sun exposure practices that put their skin health at risk.

The Science Behind Sunscreen

Understanding the science behind sunscreen formulations is essential to debunking these dangerous online myths. There are two types of sunscreens: physical (a.k.a mineral or inorganic) and chemical (a.k.a organic). For physical sunscreen, only two ingredients are approved by the Food and Drug Administration (FDA): zinc oxide and titanium dioxide. Chemical sunscreens have a much more extensive range of approved ingredients, such as avobenzone, oxybenzone, octinoxate, octocrylene, octisalate, and homosalate. Despite common public misconceptions, both physical and chemical sunscreens can achieve the same levels of SPF, and both types work by absorbing UV light and turning it into heat.

Sunscreen formulations undergo extensive testing to prove the effectiveness of the stated sun protective factor (SPF), utilizing advanced cosmetic chemistry techniques. In the United States, all sunscreens sold must have an SPF (Sun Protective Factor) listed on their label, as mandated by the FDA. SPF indicates the relative amount of time a person's skin can be exposed to UV radiation before reddening when using sunscreen, compared to unprotected exposure. For example, if a person typically starts to burn after 10 minutes of sun exposure without sunscreen, applying an SPF 10 sunscreen would theoretically allow them to stay in the sun for 100 minutes (10 times longer) before burning. However, it is important to note that sunscreen reapplication is required every two hours, no matter the SPF, because skin movement, sweat, and oil production can decrease the sunscreen's protection. More specifically, SPF 15 blocks about 93% of UVB rays, SPF 30 blocks about 97%, and SPF 50 blocks about 98%. Creating a commercial sunscreen product involves intensive regulation, expensive manufacturing equipment, and sophisticated chemistry techniques, ultimately taking over a year to be brought to market. With this understanding of sunscreen formulations, it is now important to understand the shortcomings and dangers of DIY sunscreen.

Dangers of DIY Sunscreen

Homemade sunscreens lack the sophisticated formulations required to achieve adequate SPF protection, posing severe risks to skin health. Despite this fact, online health influencers often claim that there are natural alternatives, like coconut and castor seed oil, that protect against harmful UV radiation. However, research by Kaur et al. (2010) has shown that these natural oils lack the proper SPF; specifically, coconut and castor oil have a minuscule SPF of 8 and 6, respectively. The American Academy of Dermatology recommends an SPF of 30 or higher for sufficient sun protection, a far cry from the SPF offered by natural oils. As dermatologist Dr. Daniel D. Bennett explained in an official American Academy of Dermatology statement, "Most homemade sunscreens lack effective sun protection, leaving users vulnerable to sunburn, premature skin aging, and skin cancer."

Some at-home DIY sunscreen recipes will even use active sunscreen ingredients, often zinc oxide powder, giving the individual a false sense of confidence in their homemade sunscreen. As seen in the viral Nara Smith DIY sunscreen post, combining a mixture of natural oils and zinc oxide creates a substance that seemingly looks like any other commercial sunscreen, but there is a profound difference at a molecular level. Commercial and homemade sunscreens differ in the particle size and clumping of the active ingredients, often creating a significant disparity in the SPF. In commercial sunscreens, smaller particles and less clumping allow for a larger surface area of skin to be covered entirely in a sun protective filter, creating an effective and higher SPF. A study by Couteau et al. (2021) tested fifteen DIY internet sunscreen recipes; ultimately, three did not contain any sun protection, and the 12 other recipes all had an SPF under 6. So, despite an equal percentage of zinc oxide (or other SPF filters) in a sunscreen formulation, other factors like particle size and clumping may play a significant role in the formulation.

Source: Wong, M. (2019)

The effectiveness of sunscreen is influenced not only by its active ingredients but also by its base formulation, which includes emollients, preservatives, and stabilizers. The active ingredients—chemical or physical—provide sun protection, but the base plays a crucial role in how well these ingredients adhere to the skin and remain stable under sun exposure. For instance, a poorly formulated DIY sunscreen may lack the necessary emulsifiers to ensure an even distribution of active ingredients, leading to uneven protection. Without a proper understanding of cosmetic chemistry, individuals may unknowingly compromise their skin's safety, reinforcing the importance of using commercially prepared, scientifically validated sunscreens.

The Toxicity of Sunscreen Misinformation

Beyond the baseless claims of online 'wellness' influencers, when research is cited, it is often a mischaracterization that distorts the findings to sensationalize fears. One example is a misinterpreted study showing that individuals who use sunscreen may have a higher incidence of skin cancer, including melanoma. However, this correlation is misleading; those who apply sunscreen are often the same individuals spending extended time in sunny climates and engaging in sunbathing. Consequently, the increased exposure to UV radiation, not the use of sunscreen, elevates their risk of skin cancer.

Frequently, influencers claim that chemical sunscreen filters, specifically oxybenzone, cause hormonal disruption. However, there has been no conclusive evidence that oxybenzone is harmful to humans. The study most often cited involved administering large quantities of oxybenzone to rats-doses equivalent to what a human would accumulate in 277 years of regular sunscreen use. Such findings do not translate to realistic human exposure levels and fail to account for the extensive research supporting approved sunscreen ingredients' safety.

While chemical sunscreens have been the primary focus of much controversy, physical sunscreens have not escaped online scrutiny either, often facing criticism about potential nanoparticles. Mineral sunscreen nanoparticles are microscopic particles of titanium dioxide or zinc oxide that manufacturers will use to increase the cosmetic appeal of the sunscreen on the skin, often reducing the white cast. There has been online concern over the safety of this formulation; however, dermatologist Dr. Jennifer Lin states that nanoparticles have "not been shown to penetrate beyond the level of the skin and migrate into the bloodstream," meaning that their use in sunscreen does not pose the risks that some suggest.

Currently, the FDA considers mineral sunscreen filters, zinc oxide, and titanium dioxide the only UV filters generally recognized as safe and effective (GRASE). This does not mean other chemical filters are unsafe; they remain approved for use but have yet to be deemed GRASE due to insufficient data. As research continues, it is essential for consumers to stay informed about the ingredients in their sunscreens and to choose products backed by credible studies. For consumers who err on the side of caution, wearing a broad spectrum, 30+ SPF mineral sunscreen to protect against UV radiation while minimizing the potential for other health risks is ideal.

Choose Safety Over Sensation

As sunscreen misinformation proliferates on social media, it is crucial for consumers to distinguish fact from fiction. The spread of misleading claims and DIY alternatives can undermine public health initiatives aimed at reducing skin cancer rates. Addressing this misinformation requires collaborative efforts from medical experts, regulatory agencies, and social media platforms, ensuring the public understands the importance of proper sun safety measures. While the FDA has only recognized zinc oxide and titanium dioxide as generally safe and effective, this does not justify fear surrounding other approved ingredients. Instead, we should focus on empowering individuals with accurate information about sun protection. Relying on credible sources, such as the American Academy of Dermatology and the FDA, can help consumers make proper sun protection choices. Additionally, consulting with a medical provider for personalized advice can further ensure safe and effective sun protection practices. For skin health, the best approach is prioritizing daily sunscreen application and choosing products that fit personal preferences and lifestyles. Specifically, the American Academy of Dermatology recommends using a broad-spectrum, 30+ SPF, water-resistant sunscreen and seeking shade whenever possible. Appropriately protecting your skin by following these guidelines will dramatically decrease your risk of skin cancer and prevent signs of premature aging, such as wrinkles and age spots.

Cover photo taken from Coral Guardian.