A new study has cautioned users against sun beds, which they say poses double the risk of skin cancer, much more than spending the same amount of time in the Mediterranean midday summer sun.
Dundee University researchers have also cautioned that the strength of ultraviolet radiation in sun beds used in the UK is double the advised limit.
Professor Harry Moseley, consultant medical physicist at Dundee University, said: "The development of high-power sunlamps, along with clear failures of the sun bed industry to regulate themselves effectively, is putting people at an even greater risk of skin cancer than we previously thought".
"We hope these findings will make people think twice before using sun beds, as you can't be sure how much radiation you're exposing yourself to when you try to top up a tan".
"People need to be encouraged to take better care of their skin."