In eating disorders there is a great variety of ways of presenting themselves, of symptomatic manifestations and clinical courses. For this reason it is not possible to attribute to a single cause the responsibility for these manifestations
Anorexia nervosa, bulimia nervosa and binge eating disorder – diagnostic criteria:
- Anorexia nervosa: restriction of calorie intake in relation to needs, leading to a significantly low body weight i.e. below the normal minimum (with mild severity level, BMI> 17, to extreme <15) in the context of age, gender, developmental trajectory and physical health. Intense fear of gaining weight, alteration in how the individual experiences the weight or shape of their body, excessive influence of body weight or shape on self-esteem levels, or persistent lack of recognition of the severity of the current condition of underweight.
Restricted type and binge type / purging type. - Bulimia nervosa: recurrent episodes of bingeing. An episode characterized by both of the following aspects:
a) eating over a specified period of time (eg two hours), significantly more food than most individuals would eat at the same time and under similar circumstances;
b) feeling of losing control during the episode.
Recurrent and inappropriate compensatory behaviors, at least once a week for 3 months (vomiting, laxatives, diuretics, etc.). self-esteem levels are unduly influenced by body shape and weight. - Binge eating disorder: recurrent binge eating episodes characterized by:
a) Eating significantly more food over a defined period of time (eg 2 hours) than most individuals would eat at the same time.
b) Feeling of losing control during the episode
Bingeing episodes are associated with three or more of the following:
– Eating very quickly than normal
– Eating until feeling uncomfortably full
– Eating alone due to embarrassment about how much is eating
– Feeling disgusted with oneself, depressed or very guilty after the episode
The binge occurs on average at least once a week for 3 months and is not associated with the systematic implementation of compensatory behaviors.
Theories and models
Bruch’s psychological model
The author identified severe body image disturbance, the inability to properly interpret hunger or other internal cues and the “profound paralyzing sense of inadequacy” (Bruch, 1978, p. XXII) the primary psychological dysfunction of these disorders. It was also Bruch who was the first to focus on socio-cultural influences, which are now widely studied.
She then considered triggers of eating disorders, diet and the search for a leaner body image, which even today are seen as the most likely triggers (Stice, 2001).
Cognitive models
The worry of having to lose weight and the phobic avoidance of “fatness”, connected to an excessive self-evaluation based only on one’s own weight and body shape, suggest that there is a strong component of cognitive origin in this disorder (Fairburn, 2002). Furthermore, it has recently been hypothesized that, in many patients, one or more of the four maintenance cognitive processes interact with the profound psychopathology of eating disorders, helping to maintain them and opposing their change (Fairburn et al. 2003).
Such maintenance cognitive processes are perfectionism, chronically low self-esteem, dysphoria, and interpersonal difficulties. All these cognitive difficulties are central features of these disorders; behavioral manifestations (such as food or diet restriction and binge eating and compensatory behaviors) are secondary to cognitive dysfunction (Fairburn, 2002).
Predisposing personality theory
Research carried out with the EDI (Eating Disorder Inventory – 3 eating disorder symptom assessment tool, developed to measure personality traits), show that personality traits such as perfectionism, feelings of ineffectiveness (or low self-esteem), reduced interoceptive awareness (or insensitivity to internal signals such as hunger and satiety), and interpersonal distress are found very frequently in those with an eating disorder rather than in the normal population (Garner, Olmsted, Polivy and Garfinkel, 1984; Leon, Fulkerson, Perry-Zald, 1995).
Integrated biopsychosocial model
The biopsychosocial model supports the existence of an interaction between the organism, its past behavior and its environment (biological, psychological and environmental variables). This model was, for about twenty years, considered the most important in explaining the development of eating disorders (Schlundt and Johnson, 1990).
Eating disorders would therefore be determined by several causes that interact and integrate in ways that are not yet completely clear. It is partly due to the difficulty of collecting data on the causes involved in the development of any type of psychiatric disorder.
The development of CBT treatment for anorexia nervosa.
CBT’s current frame of reference for the treatment of anorexia nervosa is based on the pioneering work of Aaron Beck and his colleagues (Beck, 1976; Beck, Rush, Shaw, and Emery, 1979), i.e. those who have developed CBT for depression.
Cognitive-behavioral therapy (CBT), cognitive therapy (CT) and behavioral therapy (Behavior Therapy – BT), are manualized therapies, structured with well-defined times and which address the beliefs and behaviors that are supposed to have caused and keep the disturbance.
Garner and colleagues (1997) describe CBT for anorexia nervosa as a therapy that deals with patients’ beliefs, attitudes, and assumptions about the significance of body weight.
Thinness is seen as the main avenue to self-esteem and worth, and weight gain is much feared. A combination of positive and negative reinforcers maintains patients’ behaviors and helps explain the ego-syntonic nature of the disease.
The main objective of CBT is to promote all the strategies that can combat these beliefs and behaviors, thus trying to normalize eating habits.
