Rambo Tribble writes: Research published in the journal Cell describes a mechanism whereby exposure to UV light leads to endorphin production in the skin. Additionally, they show that rodents exhibit the characteristics of addiction to those substances. This adds to earlier studies which demonstrated withdrawal-like symptoms in frequent tanners One of the researchers, Dr. David Fisher, commented, 'It sounds like a cruel joke to be addicted the most ubiquitous carcinogen in the world,' The researchers conclusions are subject to some scepticism, however. Addiction researcher, Dr David Belin, is quoted as opining, '... their study is going to be seminal even though their conclusions are not supported by their results.' The BBC offers nicely rounded coverage, as well.