All forms of anorexia nervosa feature behaviors of calorie restriction. When you primarily manage your weight through dieting, fasting, and excessive exercise, you may be living with restricting type anorexia nervosa.

Eating disorders involve long-term eating patterns that affect your physical, psychological, and social function. Eating disorders often stem from distressing thoughts and feelings and can involve rigid and ritualistic behaviors that resemble addiction.

Anorexia nervosa (AN) is one of a handful of eating disorder diagnoses. Around 4% of females and 0.3% of males have experienced AN at some point in their lives, and it can affect people of all ages and genders.

When AN behaviors center around severe food limitations and excessive exercise, it’s known as restrictive type anorexia nervosa or anorexia nervosa restricting type (AN-R).

AN is broken down into two subtypes by the Diagnostic and Statistical Manual of Mental Disorders, 5th edition, text revision (DSM-5-TR), a clinical guidebook used internationally in the assessment of mental health conditions.

These subtypes are:

Both subtypes of AN include the core features of energy restriction, fear of weight gain, and distorted body image. What sets them apart are the primary behaviors a person uses to achieve weight loss.

In AN-R, behaviors are focused on food restriction and excessive physical exertion. In AN-BP, food and calorie restriction is still present, but it’s intermixed with episodes of binge eating and purging behaviors, like self-induced vomiting and laxative misuse.

AN-R is one of two subtypes within the diagnosis of AN.

Subtypes allow clinicians to add specificity to your diagnosis, which can help when developing treatment plans and individualized care.

Receiving an AN-R diagnosis means no binging or purging behaviors have been present within the last 3 months, and weight loss habits mainly involve dieting, fasting, or excessive physical exercise.

Can dieting, fasting, and exercise be a part of AN-BP?

Energy restriction methods such as excessive exercise, dieting, and fasting can be seen in all forms of AN. A diagnosis of AN-BP simply means binging and purging behaviors are present.

Due to the high potential for cross-over symptoms between types, the DSM-5-TR notes AN subtypes should only be used to describe current symptoms, not the long-term course of AN.

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Symptoms are feelings, sensations, and health changes experienced by the person living with a condition. They aren’t always the same as signs of a condition that others may be able to see.

Symptoms of AN-R may include:

  • significant weight loss
  • body weight below what’s standard for your age and height
  • intense fear of weight gain or of having overweight
  • distorted perception of body size and shape
  • preoccupation with food and weight
  • poor concentration
  • hair loss
  • brittle nails
  • fatigue
  • temperature intolerance
  • irregular menstrual cycles
  • bowel changes
  • bone thinning
  • low blood pressure
  • mood swings
  • organ damage or failure

Signs a loved one is experiencing AN-R

Leslee Marcom, regional clinical director at Eating Recovery Center in Denver, Colorado, explains recognizing AN-R can be tricky. Signs aren’t always visually apparent or obvious.

“People living in larger bodies may also experience restrictive anorexia, and a patient with anorexia may appear ‘healthy’ when they are malnourished,” she says. “That’s why understanding the warning signs and symptoms of anorexia is so important.”

A loved one may be experiencing AN-R when they:

  • show significant weight loss
  • have a change in eating habits
  • regularly express concerns about weight or weight gain
  • speak negatively about themselves
  • compulsively exercise
  • engage in ritualistic eating or weight loss behaviors, like eating in isolation
  • withdraw socially
  • are frequently irritable
  • seem intolerant of being hot or cold
  • actively deny the health risks associated with low body weight
  • show a decline in energy and motivation
  • skip events and gatherings where food is served

In the United States, doctors use criteria outlined in the DSM-5-TR to diagnose AN-R.

According to these criteria, an AN diagnosis of any type may be given when the following three defining features are met:

1. Energy restriction leading to low body weight

Energy intake is restricted to below functional requirements in AN and leads to significantly low body weight in relation to age and height standards.

In children, this can look like a failure to make developmentally appropriate weight rather than an experience of weight loss.

2. Intense fear of weight gain

AN features an intense fear of gaining weight or being overweight that doesn’t go away with weight loss. According to the DSM-5-TR, preoccupation with weight tends to increase even as weight decreases.

3. Body image disturbance

Both body image experience and its significance are distorted in AN. This means how you view your body and how you relate health to weight are not aligned with reality.

Many people living with AN view themselves as overweight even though they are underweight, or they may fixate on particular body parts they perceive as “fat.”

People experiencing AN will also not be able to acknowledge the health risks associated with malnutrition and low body weight.

The specifiers

Once a diagnosis of AN has been made, your doctor will add specifiers, including subtypes, to reflect your individual experience of AN.

Specifiers in AN include subtypes of AN-R or AN-BP, as well as specifiers for severity, which are based on your calculated body mass index (BMI).

  • Mild: BMI of 17 or greater
  • Moderate: BMI between 16 and 16.9
  • Severe: BMI between 15 and 15.9
  • Extreme: BMI under 15

The exact causes of AN aren’t clear, though certain factors may increase your chances of developing this eating disorder. In AN, the risks are the same across subtypes.

“There is no single cause of eating disorders,” Marcom explains. “Anorexia stems from a complex interplay between multiple factors, including genetic, environmental, sociocultural, and psychological.”

She indicates this includes variables such as:

Other factors that may increase your risk of developing AN-R include:

  • personal history of other mental health conditions
  • a history of dieting
  • living with a chronic illness like type 2 diabetes
  • being the target of bullying
  • experiencing a physiological state known as low energy availability (LEA)
  • having low cognitive flexibility (i.e., the ability to smoothly transition between tasks)

AN treatment usually involves a multidisciplinary team of health professionals. Your primary doctor will work closely with mental health professionals and nutrition experts to ensure they cover all physical and psychological aspects of care.

“Treatment for both subtypes is very similar and, in most cases, sustainable recovery begins with nutritional rehabilitation and weight restoration,” says Marcom.

According to a report from 2022, psychotherapy is an essential component for the treatment of AN. In adolescents, the gold standard approach is family therapy, which makes caregivers active participants in a child’s recovery process.

In adults, cognitive behavioral therapy (CBT), including specific formats like exposure and response prevention (ERP) and acceptance and commitment therapy (ACT) can help challenge unhelpful beliefs about weight and food while addressing the source of psychological distress.

While no medications directly treat AN, your doctor may prescribe medications to address co-occurring symptoms like depression.

If symptoms of AN are persistent despite treatment, your healthcare team might recommend a neuromodulation procedure, like deep brain stimulation (DBS), to help regulate neural signals in your brain that contribute to AN symptoms.

Anorexia nervosa restricting type (AN-R) is one of two subtypes of AN. It features the classic symptoms of AN without any binging or purging behaviors. In AN-R, weight loss methods typically involve fasting, dieting, and excessive exercise.

Regardless of subtype, AN is treatable. Nutritional care, physical monitoring, and psychotherapy work together to bring your body back to functional levels while also addressing the underlying causes of AN.