It’s no secret that tanning beds cause skin cancer. Now there’s evidence that some of the ultraviolet rays from these beds may be even more dangerous than previously thought – and that has the “health police” renewing their call for banning teens from the beds.

Experts had only thought UVB rays – the ones that cause sunburn – were the main cause of skin cancer. But a new study suggests UVA rays – which pass through clouds and glass windows and are linked to aging and wrinkles – are just as dangerous.

“Tanning salons still tend to claim that UVA is safe, but that’s nonsense,” study author Dr. Antony Young, professor of photobiology at King’s College London, told The Daily Mail. “It may be more carcinogenic than previously thought.”