In simple words: This is an eating disorder where people are very underweight but are terrified of gaining weight. They don't eat enough food and may exercise too much.They see themselves as overweight even when they are dangerously thin.

Restricting-type anorexia nervosa is an eating disorder characterized by a significantly low body weight in the context of age, sex, developmental trajectory, and physical health. Individuals with this disorder have an intense fear of gaining weight or becoming fat, or persistent behavior that interferes with weight gain, even though at a significantly low weight. They may also experience a disturbance in the way in which one's body weight or shape is experienced, undue influence of body weight or shape on self-evaluation, or persistent lack of recognition of the seriousness of the current low body weight.This subtype is distinguished by the absence of recurrent episodes of binge eating or purging behavior. Weight loss is primarily achieved through dieting, fasting, and/or excessive exercise.

Example 1: A 16-year-old female presents with extreme weight loss, amenorrhea, and bradycardia. She restricts her food intake drastically, counts calories obsessively, and exercises excessively. She denies binge eating or purging behaviors. Her body image is distorted, and she perceives herself as overweight despite being severely underweight., A 20-year-old male college student demonstrates a preoccupation with healthy eating, which has escalated into restrictive eating patterns. He avoids entire food groups, weighs himself multiple times daily, and engages in compulsive exercise.He has experienced significant weight loss and exhibits signs of malnutrition, such as fatigue and dizziness., A 30-year-old female has a long-standing history of restrictive eating habits dating back to adolescence.She carefully controls her portions, avoids social situations involving food, and experiences intense anxiety when presented with meals she has not prepared herself. Her weight is consistently below the healthy range for her height and age.

Thorough documentation should include details of the patient's weight history, eating patterns, body image perceptions, exercise habits, and any associated psychological symptoms.Physical examination findings, laboratory results (e.g., electrolyte levels), and any co-occurring medical or psychiatric conditions should also be recorded.The specific subtype of anorexia nervosa (restricting type) must be clearly documented based on the diagnostic criteria.