What Is ‘Extreme’ Anorexia?

Extreme anorexia is the most serious form of anorexia. It occurs when a person is severely underweight and malnourished from intentionally starving themselves to lower their weight. 

Patient speaking with a doctor

Anorexia is a potentially life-threatening mental health disorder. More than 10,000 people die every year in the U.S. as a direct result of an eating disorder. 

Someone with anorexia has an intense fear of gaining weight and will have a distorted body image that will tell them they are “fat” even when they are often grossly underweight. 

Extreme and severe cases of anorexia can cause serious medical and mental health complications. They require swift, intensive, and comprehensive care as soon as possible to minimize and potentially reverse negative side effects.

What Is Extreme Anorexia?

Extreme anorexia is defined as someone having a BMI of less than 15 kg/m2. This is severely underweight, as a healthy BMI ranges from 18.5 and 24.9 kg/m2

Anorexia is defined as an eating disorder where a person meets the following criteria:

  • Obsession with weight and body image
  • Fear of gaining weight
  • Significant restriction of food and calorie intake

Someone with anorexia may use diet pills or exercise excessively to lose weight. When someone has severe anorexia, they will refuse to maintain what is considered a healthy weight for their age and height. They will use any means necessary to keep their weight low, often to the point of extreme malnutrition.

Initial Signs of Anorexia

Anorexia can often begin with a diet. Then, a person may become obsessed with dropping weight and maintaining a body image that is often undernourished and unhealthy. The disorder can also stem from genetic, biological, and environmental factors. 

It’s beneficial to understand the warning signs and initial signs of anorexia, which are as follows:

  • Dehydration
  • Skipping meals and refusing to eat
  • Restricting foods and significantly limiting calorie intake
  • Social withdrawal and secrecy
  • Refusal to eat in public or with others
  • Bloating and stomach pain
  • Frequent trips to the bathroom, often to purge or as a result of diuretics
  • Mood changes
  • Frequent talking about weight, dieting, and body shape
  • Exercising consistently and rigidly, even when conditions are not ideal
  • Sensitivity to cold and dressing in layers
  • Mental sluggishness

What Is Considered a Severe Case of Anorexia?

According to the DSM-5, which contains the diagnostic criteria for mental illnesses, extreme anorexia is classified based on a super low BMI of 15 kg/m2. 

A low BMI is not the only classification for anorexia. A person must also exhibit an intense fear of gaining weight and engage in food or calorie deprivation and/or additional methods to lose weight based on a distorted body image that leads them to believe they are overweight no matter what they look like. 

A severe case of anorexia can have a multitude of health and psychological side effects, such as these:

  • Cardiac and cardiovascular issues, including thinning of the heart walls, heart and blood flow irregularities, and the potential for sudden cardiac death
  • Changes to the structure of the brain, which can include a reduction in the size and shape of the brain as well as changes to the chemical makeup and circuitry
  • Imbalance of electrolytes, which can cause seizures
  • Low blood sugar (hypoglycemia), which can cause mood changes, trouble thinking clearly, headaches, and even seizures
  • Gastrointestinal issues, such as gastroparesis, liver disease, functional bowel disorders, and constipation
  • Reduction in white blood cell count, reduced immunity, and anemia
  • Muscle and bone density loss
  • Skin conditions, such as the growth of lanugo 
  • Depression and suicidal ideations
  • Anxiety and irritability

Difficulties of Reversing Extreme Side Effects of Anorexia

The more severe the side effects of anorexia are, and the longer the body has been deprived of essential nutrients, the more significant the damage to the brain and body can be. Much of the damage done by starvation and malnutrition can be reversed, but there is a correlation between the severity of the damage and the timeline required for any reversal. 

Damage to the brain, central nervous system, organs, and cardiovascular system may not be completely reversible. Structural changes to the brain can be long-lasting with chronic and long-term extreme anorexia.

Dangers of Putting off Treatment for Anorexia

Putting off treatment for anorexia can increase potential complications, make extreme side effects harder to reverse, and even be fatal. 

People with anorexia may experience seizures and cardiac arrest. They are also often at a higher risk for suicide. 

Without swift treatment, medical and mental health complications will be more pronounced and recovery will be more complicated and prolonged. Early intervention for anorexia, with comprehensive medical and mental health treatment, is essential for optimal outcomes.


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Last Update | 09 - 16 - 2022

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