CHICAGO — More than half a million U.S. teens have had an eating disorder but few have sought treatment for the problem, government research shows. the study is billed as the largest and most comprehensive analysis of eating disorders. it involved nationally representative data on more than 10,000 teens aged 13 to 18. Binge-eating disorder was the most common, affecting more than 1.5 percent of kids studied. Just under 1 percent had experienced bulimia, and 0.3 percent had had anorexia. overall, 3 percent had a lifetime prevalence of one of the disorders. Another 3 percent of kids questioned had troubling symptoms but not full-fledged eating disorders. the study was released online Monday in Archives of General Psychiatry. the rates are slightly higher than in other studies. and the study is based on kids and parents interviewed over two years ending in 2004. but co-author and researcher Kathleen Merikangas of the National Institute of Mental Health says similar rates likely exist today. More than half the affected teens had depression, anxiety or some other mental disorder. Sizeable numbers also reported suicide thoughts or attempts. Merikangas said the results underscore the seriousness of eating disorders. ___ Online: NIH: health.nih.gov/topic/EatingDisorders Journal: archpsyc.ama-assn.org/