"The incidence of anorexia nervosa is around eight per 100,000 persons per year. An upward trend has been observed in the incidence of anorexia nervosa in the past century till the 1970s. The most substantial increase was among females aged 15-24 years, for whom a significant increase was observed from 1935 to 1999. The average prevalence rates for anorexia nervosa and bulimia nervosa among young females are 0.3 and 1%, respectively. Only a minority of people with eating disorders, especially with bulimia nervosa, are treated in mental healthcare."