CALGARY — Claims that sunscreen causes cancer have continued to circulate online despite research identifying ultraviolet (UV) radiation, not sunscreen, as the primary cause of most skin cancers.A recent BBC Verify report examined how those claims spread, tracing many of them to influencers and online personalities who cited a 2023 study from the U.K. Biobank. Posts promoting the study claimed regular sunscreen users faced dramatically higher rates of skin cancer, with some describing it as the "largest sunscreen study ever conducted."The study found an association between frequent sunscreen use and higher rates of skin cancer, but it did not conclude that sunscreen causes the disease. Instead, researchers said the findings likely reflect the fact that people who use sunscreen most often are also those who receive the greatest exposure to ultraviolet (UV) radiation through work, recreation or repeated time in the sun.Canadian health authorities have reached the same conclusion. According to the Government of Canada, skin cancer is the country's most common cancer, accounting for about one-third of all new cancer diagnoses. .While melanoma represents only about 5% of skin cancer cases, it causes the majority of skin cancer deaths because it is more likely to spread if left untreated.The Canadian Cancer Society estimates that approximately 11,300 Canadians will be diagnosed with melanoma in 2026, and about 1,250 people will die from the disease. Based on current rates, roughly one in 59 Canadian men, and one in 73 Canadian women will develop melanoma during their lifetime.Health Canada recommends using broad-spectrum sunscreen with an SPF of 30 or higher as part of a broader sun protection strategy that also includes seeking shade, wearing protective clothing and limiting sun exposure during peak UV hours.Much of the attention has centred on chemical UV filters including oxybenzone, octinoxate and octocrylene. Researchers have continued to examine these ingredients for factors such as absorption into the bloodstream, potential hormone-related effects seen in laboratory studies and environmental impacts. Health Canada says current scientific evidence does not show that sunscreen ingredients approved for use in Canada cause cancer when used according to their directions..Some public concern also stems from a series of sunscreen recalls in 2021, when several aerosol sunscreen products, including brands manufactured by Johnson & Johnson and Coppertone, were voluntarily recalled after testing detected benzene contamination.While benzene is a known human carcinogen, health authorities stressed that it was not an approved sunscreen ingredient.Regulators emphasized that the recalls were specific to the affected batches and did not indicate that sunscreen itself or its approved active ingredients cause cancer.Both the evidence reviewed by the BBC and guidance from Canadian health authorities point to the same conclusion: there is no credible evidence that approved sunscreen products cause cancer when used as directed.Instead, research has continued to identify excessive exposure to ultraviolet radiation as the far greater risk, making sunscreen one of several recommended tools to help reduce the likelihood of developing skin cancer.
