Symptoms of Anorexia Nervosa
Anorexia nervosa presents with three core diagnostic features: persistent restriction of energy intake leading to significantly low body weight, intense fear of gaining weight or persistent behavior that interferes with weight gain, and disturbance in how one's body weight or shape is experienced. 1
Psychological and Behavioral Symptoms
The psychological manifestations are central to diagnosis and include:
- Distorted body image where patients perceive themselves as overweight despite being significantly underweight, with self-worth becoming overly based on body shape and weight 1, 2
- Intense fear of weight gain or becoming fat, even when at dangerously low body weight 1, 3
- Persistent lack of recognition of the seriousness of their current low body weight 1
- Lower self-esteem, negative body image, and feelings of inadequacy compared to peers with normal eating patterns 2
- Anxiety, depression, social dysfunction, and moodiness are characteristic psychological features 2
Physical and Medical Symptoms
The physical manifestations result from severe malnutrition and include:
- Significantly low body weight in context of what is minimally expected for age, sex, developmental trajectory, and physical health 1, 3
- Amenorrhea (absence of menstrual periods) in females 4
- Delayed gastric emptying of solids and delayed small and large bowel transit 1
- Hypothermia, bradycardia, and hypotension, particularly in those who have lost large amounts of weight rapidly 3
- Cardiac complications, which are responsible for at least one-third of all deaths in anorexia nervosa 2
Behavioral Patterns
Observable behaviors that signal anorexia nervosa include:
- Persistent restriction of energy intake through extreme dietary limitations 1, 3
- Excessive exercise as a compensatory behavior 5
- Relentless pursuit of thinness despite already being underweight 4
In the binge-eating/purging subtype, additional symptoms include:
- Recurrent episodes of binge eating characterized by consuming larger amounts of food than most people would eat in similar circumstances with a sense of lack of control 3
- Purging behaviors such as self-induced vomiting, misuse of laxatives, diuretics, or other medications 3
Critical Clinical Warning
A dangerous pitfall is assuming normal laboratory results exclude serious illness—more than half of adolescents with eating disorders have normal test results despite being medically unstable. 2 This means you cannot rely on laboratory values alone to assess severity; clinical presentation and vital signs are paramount.
High-Risk Demographics
- Adolescent and young adult females between ages 13-20 years are most affected, with a female-to-male ratio of approximately 9:1 2, 3
- Adolescent girls involved in competitive sports and dancing face particularly high risk due to performance pressures combined with aesthetic expectations 2
- Girls who diet are 18 times more likely to develop an eating disorder than non-dieters 2
Treatment Approach
Early detection and immediate medical and psychological treatment are critical, as complications develop rapidly in malnourished adolescents. 2 The mortality rate for anorexia nervosa is among the highest for any psychiatric disorder, with cardiac complications being the leading cause of death. 2, 3
For adolescents with involved caregivers, eating disorder-focused family-based treatment is the recommended approach 6. For adults, eating disorder-focused cognitive-behavioral therapy (CBT) is recommended, with some evidence that fluoxetine may help prevent relapse in weight-restored patients 4, 7. However, treatment efficacy remains limited, and an interdisciplinary team approach including nutritional rehabilitation and psychosocial therapies is essential. 5, 8