Young people should be banned from using sunbeds, one of the UK's top skin experts has suggested.
Sunbeds are particularly popular with young women
Professor Antony Young of King's College London made the call after reviewing all the major studies into sunbed use over the past 20 years.
Professor Young said there was now "pretty strong" evidence that sunbeds can cause skin cancer.
Writing in the journal Pigment Cell Research, he said he was concerned so many people continue to use sunbeds.
Professor Young reviewed more than 60 pieces of research as part of his study.
Most suggested there was a link between sunbeds and skin cancer. However, others did not.
"The earliest studies did not tend to show a link," he told BBC News Online.
"However, with time the link becomes more convincing and the studies are better done."
Professor Young said he was now reasonably sure there may be a link.
"The evidence is not 100% conclusive but I think it is pretty strong."
Professor Young urged people who use sunbeds not to use them too often.
"My advice would be to restrict the number of sessions to a maximum of 20 a year," he said.
"One of the things that concerns me is that a significant minority of people, particularly young women, regularly use sunbeds to get a tan.
"If they use sunbeds year in year out they may increase their risk of skin cancer."
However, he said people who do not tan easily should avoid sunbeds altogether while laws should be introduced to ban under 18s from using the machines.
"Effective laws could limit the use of sunbeds by young people at commercial facilities."
Kathy Banks of the UK's Sunbed Association cited a recent study which suggested sunbeds did not cause skin cancer.
"The Luxembourg Health Institute conducted a study to assess whether there was an association between sunbed use and melanoma.
"The study did not support the possibility that sunbed use could increase the melanoma risk and the results indicated that if an association between sunbed use and melanoma truly existed, then it must be marginal."