What causes a teenage eating disorder?

Binging: Biopsychosocial factors; predisposition, self esteem, and social pressures.

Nature/nurture: This is a great question & many are not aware of recent research advances. Eating disorders have among the highest genetic component of any psychiatric disorder. For anorexia, losing weight in ways that are harmless to others, likely leads to a downward spiral where compulsive weight loss behaviors take over. In bulimia, the intensity of uncontrolled binges likely triggers purging.