Research on eating disorders has shown that it is not possible to attribute only one cause to an eating disorder development.

Eating disorder development has been described as a three-phase process where the presence of certain risk factors creates a predisposition to fall ill; for this reason some people become more vulnerable to eating disorder development.
When these more vulnerable people have to face up to very stressful events, there is a high probability that they will develop an eating disorder rather than psychological, psychosomatic or other kinds of pathology.

When the eating disorder is stable, it is prone to self-maintenance.

There are different factors that predispose people to develop an eating disorder. Some predisposing factors are:

• Being a woman. It is undeniable that a woman is more subject to the slimness cult than a man.
• Being between the ages of 15 and 35. Eating disorders reach their peak in this age bracket.
• Suffering from depressive disorders and having particular personality traits.
• Being overweight. It has been noticed that many eating disorders begin with a strict diet in overweight people.
• Having a family where weight and body fitness are considered important problems.
• Having been victims of sexual abuse during childhood and adolescence. An incidence of abuse victims is of statistical importance in eating disorder patients.
• Growing up in a family that had not transmitted enough self-esteem, trust in oneself and the capacity to recognize and elaborate emotions.

The presence of two or more factors will create in people a predisposition to suffer from eating disorders that will be stronger as the factors increase.