karen had anorexia nervosa, an eating disorder of extreme weight loss dieting. this was a little-known illness at the time. although she had begun recovery with a doctor-supervised program and regained 30 lbs (14 kg), permanent damage to her body had been sustained from the years of extreme weight-loss dieting and she died at the age of 32. the cause of her death was heart failure, from complications related to her illness which caused her to believe mistakenly that she needed to lose weight.