What Is It?
Anorexia nervosa is a serious eating disorder marked by intense fear of gaining weight, distorted body image, and severe food restriction leading to dangerously low body weight. People with anorexia may also engage in excessive exercise, purging, or other behaviors to avoid weight gain. Despite being underweight, individuals often see themselves as overweight.

Why It Matters
Anorexia has the highest mortality rate of any mental health disorder, due to both medical complications (e.g., organ failure, heart problems) and suicide. Early intervention significantly improves outcomes. Anorexia nervosa is not a lifestyle choice—it’s a complex psychiatric condition that often requires multidisciplinary treatment involving mental and physical health care.

Key Facts (At a Glance)

• Prevalence: Affects approximately 0.5% to 1% of the U.S. population

• Typical Onset: Adolescence or early adulthood

• Gender: Most common in females, though increasing in males and nonbinary individuals

• Comorbidities: Frequently occurs with anxiety, depression, or obsessive-compulsive disorder (OCD)

• Types:

  • Restricting Type: Weight loss through fasting, dieting, or excessive exercise

  • Binge-Eating/Purging Type: Includes episodes of binge eating and/or purging (e.g., vomiting, misuse of laxatives)

How It Affects the Body
Chronic undernutrition affects nearly every body system. As body fat and muscle waste away, the body slows down to conserve energy. This can lead to bradycardia (slow heart rate), hypotension (low blood pressure), amenorrhea (loss of menstrual cycle), osteopenia, and multi-organ failure. Electrolyte imbalances caused by purging can lead to cardiac arrest. Brain function is also impacted, contributing to difficulty concentrating, depression, or obsessional thoughts about food and weight.

Common Symptoms

• Significant weight loss or failure to gain expected weight during growth

• Extreme food restriction or “safe” food lists

• Fear of gaining weight, even when underweight

• Distorted body image or denial of low body weight

• Preoccupation with food, dieting, calories, and body image

• Excessive exercise

• Skipping meals, cutting food into small pieces, or eating in secret

• Cold intolerance and lanugo (fine body hair)

• Missed periods or other hormonal changes

• Social withdrawal or irritability

Risks & Side Effects

• Heart problems (bradycardia, arrhythmias, heart failure)

• Electrolyte imbalances (especially potassium)

• Gastrointestinal issues (constipation, bloating)

• Osteoporosis or bone loss

• Infertility and menstrual irregularities

• Cognitive impairment and memory issues

• Organ failure, particularly kidneys and liver

• Suicidal thoughts or actions

• Death due to starvation or complications

Who Should Be Cautious

• Teens and young adults, particularly under high pressure or perfectionist environments

• Individuals with a family history of eating disorders, depression, or anxiety

• Athletes, dancers, or performers in weight-sensitive sports

• People with trauma, bullying, or body image issues

• Social media users exposed to “thin ideal” content

When to See a Doctor
Seek professional help if you or someone you know:

• Drastically limits food intake or displays fear of weight gain

• Has unexplained weight loss or physical symptoms (fatigue, fainting, hair loss)

• Shows obsessive food-related behaviors or exercise patterns

• Experiences missed periods or growth delays

• Shows emotional distress, especially tied to eating or body image
  Diagnosis involves physical exams, psychological assessments, and nutritional evaluations.

Related Conditions / Interactions

• Bulimia nervosa or binge eating disorder (can occur sequentially or simultaneously)

• Depression, OCD, and anxiety disorders

• Body dysmorphic disorder (BDD)

• Substance use (in some cases as coping)

• Can interact dangerously with laxatives, diuretics, or weight loss supplements

Last Updated: June 15, 2025