Sun tanning can be highly addictive and often has more to do with how it makes people feel than with how they look, says a US dermatologist who is visiting Australia.
Ultraviolet (UV) light causes cells to release endorphins, the feel-good hormone, says Prof Feldman, a speaker at the annual scientific meeting of the Australasian College of Dermatologists.
"It's like a little hit of morphine."
This explains why some people continue tanning even though it is turning their skin leathery.
"We see patients in their 20s who look like they are in their 40s. They are clearly not tanning to look good, because they look terrible."