Eating Disorders — Anorexia, Bulimia
Anorexia nervosa, bulimia nervosa and binge eating disorder. Neurobiological basis, diagnostic approach and modern treatment options by psychiatrist Paschalis Gkikas in Athens.
Eating Disorders — Anorexia, Bulimia
Eating disorders are not a lifestyle choice or a matter of “willpower”. They are serious psychiatric conditions with among the highest mortality rates of all mental health disorders. Early recognition and personalized treatment can radically change the outcome.
What are eating disorders?
Eating disorders are characterized by pathological behaviors and attitudes toward food, weight and the body, with serious effects on physical health and psychosocial functioning. ICD-10 (F50) and DSM-5 distinguish the following main clinical entities:
- Anorexia Nervosa (F50.0): Intensive food restriction, intense fear of weight gain and distorted body image, despite low body weight. Mortality reaches 5–10% — the highest of any psychiatric disorder.
- Bulimia Nervosa (F50.2): Cycles of binge eating and compensatory behaviors, such as vomiting, laxatives or excessive exercise. Body weight often remains within the normal range, making the disorder “invisible”.
- Binge Eating Disorder (F50.8): Recurrent episodes of uncontrolled overeating without compensatory behaviors — the most common eating disorder in the general population.
- Avoidant/Restrictive Food Intake Disorder (ARFID, F50.82): Avoidance of foods because of sensory characteristics, fear of choking or lack of interest — without distorted body image.
Clinical presentation and symptoms
Eating disorders often hide behind an outwardly normal appearance.
Behavioral symptoms
- Strict dietary rules and rituals around food
- Avoidance of shared meals or social situations involving food
- Disappearing after meals
- Secretive food consumption
- Excessive and compulsive exercise
Physical symptoms
- Significant weight change, either loss or gain
- Amenorrhea
- Weakness, dizziness, syncope
- Dental erosions induced by vomiting
- Electrolyte disturbances — potentially life-threatening
Psychological symptoms
- Distorted perception of body image
- Guilt, shame, secrecy
- Excessive anxiety around calories and weight
- Comorbid depression, anxiety disorder or OCD
Neurobiological basis
Eating disorders cannot be explained by social pressure alone. They have a measurable neurobiological substrate:
- Serotonergic dysfunction: Disrupted reward and satiety processing — the brain does not receive the normal “enough” signal.
- Dopaminergic reward system: In binge eating, food activates the same pathways as addictive substances.
- Abnormal interoceptive processing: The brain does not correctly recognize hunger or fullness.
- Amygdala and insula: Hyperactivity in response to body- and food-related stimuli.
- Genetic vulnerability: Twin studies show heritability of 50–80% for anorexia nervosa.
Treatment approach
Effective treatment of eating disorders requires an interdisciplinary team. Psychiatrist Paschalis Gkikas undertakes psychiatric coordination, collaborating with dietitians and psychotherapists when required.
First-line treatments
- Medical stabilization: In severe cases, management of physical complications such as electrolyte disturbances, cardiac arrhythmias and malnutrition comes before any other intervention.
- CBT-E psychotherapy (Enhanced Cognitive Behavioral Therapy): The evidence-based protocol for bulimia and BED — restructures cognitive patterns around body, weight and control.
- Pharmacotherapy with PGx: SSRIs, particularly high-dose fluoxetine, are the approved pharmacological option for bulimia. Pharmacogenomic analysis helps ensure optimal molecule selection from the outset.
- Family-Based Treatment (FBT): Proven effectiveness, especially for adolescents with anorexia nervosa.
Second-line and resistant cases
- rTMS: Emerging therapeutic option for resistant anorexia nervosa, targeting the dorsolateral prefrontal cortex. Available data suggest it may be used as an adjunctive treatment in patients for whom conventional interventions have not produced the expected results.
- Treatment of comorbidity: Treatment of coexisting depression, OCD or anxiety disorder is integral — often the eating disorder is a secondary expression of another primary psychiatric condition.
There is no “typical” profile of a patient with an eating disorder. The treatment plan designed by Paschalis Gkikas always begins with meticulous psychiatric assessment — not routine protocols.
Frequently asked questions (FAQ)
Can someone with anorexia nervosa have “normal” weight?
Yes. So-called “atypical anorexia” appears in people with normal or even increased weight who meet all other criteria. Diagnosis is not based exclusively on body weight.
Are eating disorders more common in women?
They occur mainly in women, but prevalence in men is significantly underestimated because of stigma and different clinical presentation. It is estimated that 1 in 3 people with BED is male.
What is the role of the family in treatment?
Central — especially for adolescents. Family-Based Treatment (FBT/Maudsley) is considered the gold standard for young people with anorexia nervosa. For adults, family support remains a critical prognostic factor.
When is hospitalization needed?
When there are serious physical complications, such as BMI below 15, cardiac arrhythmias, electrolyte crises, or suicidal ideation. The decision for hospitalization is always individualized.
