Sun worshippers beware: tanning may be addictive, study warns
Chronic exposure to ultraviolet radiation triggers same response as heroin, study says
This may give dedicated sun worshippers reason for pause. A new study suggests that regular tanning may not only raise the risk of skin cancer but be addictive.
A study published last week found that chronic exposure to ultraviolet radiation triggers the release of endorphins - the so-called feel-good hormones - that function through the same biological pathway as highly addictive opiate drugs such as heroin and morphine.
The study involved laboratory mice, but the researchers said they believe the findings are applicable to people because the biological response of skin to UV radiation in mice is so similar to humans.
Regular UV radiation exposure led to physical dependence and addictive behaviour in the mice, the study found. The animals even exhibited withdrawal symptoms - shaking, tremors and teeth chattering - after being treated with a drug that blocked the endorphin activity, the researchers said.
Writing in the journal Cell, they said the addictive nature of UV exposure "may contribute to the relentless rise in skin cancer incidence in humans".
"There is this dangerous addictive pathway operating," said dermatologist Dr David Fisher of Massachusetts General Hospital and Harvard Medical School in the US, who led the study.
Fisher said in theory sun-related skin cancer should be highly preventable merely by reducing exposure, but the addictive qualities of UV exposure may help explain the dogged "sun-seeking behaviour" some people display through outdoor and indoor tanning and other pursuits.