A video posted by Dr Debora Rasio, an oncologist and researcher, instructed viewers not to use sunscreens ‘continuously’, asserted that the sun does not cause melanoma, and suggested that sunscreens could increase the risk of skin cancer. The clip gathered hundreds of thousands of views and triggered immediate condemnation from dermatologists, oncologists and science communicators.

Paolo Ascierto, president of the Fondazione Melanoma and an internationally recognised oncologist, issued a public rebuttal, describing the messages as ‘completely distorted, if not openly false’. He restated the established evidence that ultraviolet radiation causes genetic mutations in skin cells that accumulate into cancer, that sunburns – particularly in childhood – double the lifetime risk of melanoma, and that broad‑spectrum sunscreens with SPF 30 or higher are an essential protective measure. Ascierto added that several doctors planned to report Rasio to the medical board.

Rasio later published a second video defending her stance and introducing a further claim: that applying sunscreen during pregnancy cuts vitamin D production and thereby raises the risk of autism, ADHD and schizophrenia in children. She displayed two studies – a 2025 Danish study in Lancet Psychiatry and a 2024 study in Scientific Reports. A fact‑check by the Italian outlet Open found that neither study mentions sunscreen nor establishes a causal link between sunscreen use and neurodevelopmental disorders. The original paper that Rasio cited for the melanoma claim, an analysis of 470,000 people, itself explains the apparent paradox: heavy sunscreen users tend to stay longer in the sun, reapply the product insufficiently, or have a history of skin cancer that prompts greater protection. The study’s authors conclude that sunscreens should be used correctly, not avoided.

The episode illustrates how unevidenced health claims can spread rapidly on social media. Ascierto noted that he was ‘happily surprised’ to see many users in the comment section demanding sources and defending the scientific evidence, a sign, he said, that critical awareness is growing.