ED are mental disorders which often lead to serious medical complications such as hormone disturbances, osteopenia/osteoporosis, and myopathy. More than 90% of females with anorexia nervosa (AN) have osteopenia, and almost 40% have osteoporosis. Osteoporosis in the European Union is estimated to cost 37 billion euros each year, and the majority of persons with osteoporosis are untreated. Although economic analysis of osteoporosis in Norway is lacking, the prevalence of osteoporosis in Norway is among the world's highest.