Homemade, or do-it-yourself (DIY), sunscreen has emerged as a new trend, but how much faith should consumers place in it? During a session on the broader risks associated with cosmetics at the Francophone Congress of Allergology (CFA) 2026, Françoise Giordano-Labadie, MD, of the Dermatology Department at Paul Sabatier University at Larrey Hospital in Toulouse, France, addressed the issue and voiced skepticism.

Giordano-Labadie emphasized that homemade sunscreens can be risky because unlike commercial products, they are not regulated or tested for effectiveness. She noted that their water resistance, shelf life, and ability to protect against skin cancer with repeated ultraviolet (UV) exposure are often unknown.

To support her argument, the speaker presented several studies that do not supportthe use of these noncommercial sunscreens.

A Growing Trend

Given the rising incidence of skin cancer, it is important to protect yourself from the sun by limiting sun exposure and using UVA- and UVB-blocking sunscreens with a sun protection factor (SPF) of at least 30.

However, recent studies have raised concerns about certain ingredients in sunscreens that may have harmful effects on the marine environment, cause allergic reactions, and act as endocrine disruptors.

Consumer concerns about the health and environmental risks linked to conventional sunscreens have fueled interest in natural alternatives. As a result, homemade sunscreen recipes have proliferated online, many of them lacking compliance with current safety and quality standards.

What Is the Scientific Evidence?

To assess the effectiveness and safety of these creams, American researchers set out to evaluate 189 homemade sunscreen recipes available on the social media platform Pinterest.

The results found that 95.2% of the recipes claimed to be effective. SPF claims appeared in 33.3% of the recipes, with reported values ranging from SPF 20 to SPF 50.

However, 68.3% of the recommended recipes provided insufficient protection against UV rays. The authors noted that in this sample of posts, 41.8% had been saved by other users between one and more than 21,000 times, indicating significant interest in “health” information from this social media platform. “This study revealed widespread interest in and acceptance of inadequate information regarding sun protection,” the authors noted.

More recently, the authors of an Australian study tested the effectiveness of a natural, homemade sunscreen posted online by a wellness blogger to determine its photoprotective properties — beyond its ability to protect against erythema — compared with a commercially available SPF 50+ sunscreen.

The DIY cream contained almond oil, coconut oil, shea butter, beeswax, red raspberry seed oil, carrot seed oil, and zinc oxide. Skin explants were treated with either a commercial SPF 50+ sunscreen or the homemade sunscreen before being exposed to UV rays.

Analysis of these skin explants showed that the homemade cream reduced UV-induced damage to DNA and epidermal thickness but did not effectively protect against the formation of sunburn cells. In comparison, the SPF 50+ sunscreen provided effective protection against all parameters studied.

The researchers concluded that there is currently no evidence supporting the effectiveness of homemade sunscreen in preventing skin carcinogenesis. They explained that enhanced DNA repair in the first few hours after irradiation does not necessarily mean that apoptosis is prevented 24 hours after UV exposure. They therefore recommended the continued use of approved commercial sunscreens.

Finally, in practice, errors in preparing homemade sunscreen formulations cannot be ruled out, particularly when using approximate measurements such as cups, teaspoons, or tablespoons, which can result in formulations that vary from person to person.

Without rigorous testing and regulation, as is the case with commercial sunscreens, DIY sunscreens can result in highly variable levels of photoprotection and thus potentially increase the risk for skin cancer.

Additionally, the absence of so-called chemical preservatives requires very strict hygiene conditions and increases the risk for bacterial contamination or mold growth.

Giordano-Labadie disclosed having no relevant financial relationships.

This story was translated from Medscape’s French edition.