Sunscreen Doping: FDA Regulations & Ingredient Transparency Concerns

The seemingly simple act of applying sunscreen has become increasingly complex, shadowed by a practice some experts are calling “sunscreen doping.” This involves manufacturers listing active UV filters – the ingredients that actually protect skin from cancer – under the “inactive ingredients” section of product labels. While not inherently dangerous, this practice raises significant questions about regulatory oversight, transparency, and consumer understanding of what they’re applying to their skin.

The issue stems from the Food and Drug Administration’s (FDA) historically slow process for approving new sunscreen ingredients. Since 1999, only one new active ingredient, bemotrizinol, has been proposed for approval, formally proposed in December 2025. This bottleneck, coupled with restrictions on the concentration of approved active ingredients, has led some companies to seek workarounds. By classifying UV-absorbing chemicals as “inactive,” they bypass the rigorous testing and approval process required for active ingredients, allowing them to boost SPF levels and make certain formulation claims.

What is ‘Sunscreen Doping’ and Why Does it Matter?

Lindsay Gunnell, MD, assistant professor of dermatology at the University of Washington School of Medicine, explains that sunscreen doping exploits a gray area in ingredient definitions. “Active ingredients are those that protect the skin from skin cancer,” she says. “Inactive ingredients are supposed to be inert and make the formula cosmetically pleasing.” However, the chemical structures of some “inactive” ingredients are remarkably similar to those of approved active filters. Butyloctyl salicylate, for example, closely resembles octisalate, both being phthalates with UV-protective properties.

This distinction is crucial because it dictates the level of scrutiny applied to these ingredients. Active ingredients undergo extensive safety testing as over-the-counter drugs, while inactive ingredients are regulated as cosmetics, a process with a much faster approval timeline. Companies are essentially “hacking the system,” as Dr. Gunnell puts it, to achieve desired SPF levels and formulation aesthetics without navigating the lengthy drug approval process.

Transparency and the Mineral Sunscreen Myth

The practice of sunscreen doping has particularly significant implications for consumers seeking mineral-only sunscreens. These formulations, typically containing zinc oxide and titanium dioxide, are often marketed as safer alternatives, sitting on top of the skin rather than being absorbed. However, Dr. Gunnell’s research reveals that the vast majority of sunscreens labeled as “mineral-only” actually contain butyloctyl salicylate – the most frequently used “doping” ingredient in the U.S.

This lack of transparency is concerning because consumers choosing mineral sunscreens may be attempting to avoid specific chemicals. While butyloctyl salicylate has a good safety record, the available data isn’t as robust as that for active sunscreen ingredients used internationally. This raises questions about why the U.S. Isn’t adopting ingredients with a longer track record of safety and efficacy, as is common in other parts of the world.

Boosting SPF, But Not Necessarily Broad Spectrum Protection

While sunscreen doping can increase SPF, it doesn’t necessarily translate to better overall protection. SPF primarily measures protection against UVB rays, which cause sunburn. UVA rays, responsible for skin aging and as well contributing to skin cancer, require broader spectrum protection. Boosting SPF through doping often focuses on UVB protection, leaving a potential gap in UVA coverage.

Dr. Gunnell emphasizes that the U.S. Is missing key sunscreen ingredients available elsewhere that offer superior broad-spectrum protection. “Essentially, when we engage in sunscreen doping, we are upping the SPF factor without making the sunscreen broad-spectrum,” she explains. “Which means that consumers may be more protected from burning, but not more protected from skin aging or skin cancer.”

Potential Health Risks and Allergic Reactions

Beyond the issue of transparency, sunscreen doping also presents potential health risks, particularly for individuals with allergies. Someone with a known allergy to chemical sunscreen ingredients might choose a mineral formulation to avoid those triggers. However, if that mineral sunscreen contains a “doped” ingredient with a similar chemical structure, an allergic reaction could still occur.

What we have is especially concerning for children, as there’s limited data on the safety of chemical sunscreens in pediatric populations. Parents often opt for mineral sunscreens for their children, believing they are avoiding potentially harmful chemicals. The presence of undeclared ingredients could undermine that intention.

A Flawed Regulatory System?

Dr. Gunnell believes that sunscreen doping is a symptom of a larger problem: a flawed regulatory system. She argues that the FDA’s approach to sunscreen ingredients is backwards, hindering access to potentially more effective and safer options. “When I have talked to Congress about making sunscreen a top priority, I am often told that we have enough sunscreen ingredients in the U.S.,” she says. “While it is true that we have several approved UV filters, our sunscreens are not working as well as they ought to.”

The current system, she explains, prioritizes bureaucratic hurdles over scientific evidence. Ingredients with a long history of safe and effective use in other countries are often unavailable in the U.S. Due to the lengthy and costly approval process. This forces manufacturers to seek workarounds, like sunscreen doping, to meet consumer demand for high-SPF, broad-spectrum protection.

What’s Next for Sunscreen Regulation?

The FDA’s recent proposal to add bemotrizinol to the list of approved active ingredients is a step in the right direction, but Dr. Gunnell believes more comprehensive reform is needed. She advocates for a liberalization of sunscreen ingredient regulations, allowing access to a wider range of proven and safe filters.

Dr. Gunnell hopes to raise awareness about sunscreen doping without causing undue alarm. “The term ‘sunscreen doping’ might sound dangerous, but I do not believe it is,” she says. “The truth is that our regulation of sunscreen is completely backwards. These compounds are safe, and the benefit of using sunscreen far outweighs the risk.” She encourages consumers to continue using sunscreen as part of a comprehensive sun protection strategy, while also advocating for greater transparency and regulatory reform.

For more information, Lindsay Gunnell, MD, can be reached directly.