Pittsburgh Tribune-Review (Internet / Print) 06/02/06 http://www.pittsburghlive.com/x/pittsburghtrib/news/health/s_456317.html Is sunlight the new drug of choice? No matter how many studies prove that overexposure to ultraviolet rays can cause skin cancer, people continue to frequent tanning salons to jump-start their beach bronze -- as many as 30 million customers a year, according to the Indoor Tanning Association. Why can't they kick the habit? New research suggests the feel-good effects of UV light on the skin might be addictive. A study by the University of Texas Medical Branch at Galveston says tanners can develop a mild dependence on the endorphins that are released when tanning, which produce a sort of "runners' high."