Tanning beds mutate skin cells far beyond the reach of ordinary sunlight, study shows

Source: Medical XPress

Tanning bed use is tied to almost a three-fold increase in melanoma risk, and for the first time, scientists have shown how these devices cause melanoma-linked DNA damage across nearly the entire skin surface, reports a new study led by Northwestern Medicine and University of California, San Francisco.

Melanoma, the deadliest skin cancer, kills about 11,000 in the U.S. each year. Despite decades of warnings, the precise biological mechanism behind tanning beds' cancer risk remained unclear. The indoor tanning industry, which is making a comeback, has used that uncertainty to argue that tanning beds are no more harmful than sunlight.

This new study "irrefutably" challenges those claims by showing how tanning beds, at a molecular level, mutate skin cells far beyond the reach of ordinary sunlight, according to the authors.

"Even in normal skin from indoor tanning patients, areas where there are no moles, we found DNA changes that are precursor mutations that predispose to melanoma," said study first author Dr. Pedram Gerami, professor of skin cancer research at Northwestern University Feinberg School of Medicine. "That has never been shown before."

Read more: https://medicalxpress.com/news/2025-12-tanning-beds-mutate-skin-cells.html