Atypical Anorexia Nervosa: Causes, Symptom, and Treatment

Atypical anorexia nervosa includes all the signs and symptoms of anorexia nervosa with the exception that those with atypical anorexia are not underweight.

In fact, people with atypical anorexia are within or above what is considered a normal weight range. As is characteristic of all types of anorexia, they’ve undergone significant weight loss due to restrictive caloric intake. Having atypical anorexia nervosa doesn't mean you require any less help or treatment than those with typical anorexia.

Atypical Anorexia Nervosa in the DSM

Traditionally, eating disorders like anorexia has been characterized by low body weight. However, in the American Psychiatric Association's Diagnostic and Statistical Manual (DSM-5), published in 2013, atypical anorexia was included in the category Other Specified Feeding or Eating Disorders (OSFED).

Diagnostic Criteria

Diagnostic criteria for anorexia include:

• Taking in an inadequate number of calories
• A fear of gaining weight
• Beliefs that body size impacts self-worth

Atypical Anorexia Is Often Misdiagnosed or Overlooked

Even though people who have atypical anorexia show the same symptoms as people with anorexia, the fact that they're not underweight leads to people overlooking or misdiagnosing them.

In fact, parents and doctors may even praise the weight loss of those with atypical anorexia because, even though the speed with which they’ve lost the weight is unhealthy, they don’t "look" sick or emaciated.

However, it's important to note that we can't necessarily see if someone is sick—not from their body, shape, or appearance. It's important to look beyond someone's appearance and not assume that someone is healthy, or not healthy, from how they look.

Causes of Atypical Anorexia Nervosa

The causes of atypical anorexia are the same as those of other eating disorders. And while the causes of eating disorders in general are not especially well understood, there are a number of risk factors that may leave certain people more vulnerable.

These risk factors can be genetic, psychological, or sociocultural, and include:

• An immediate family member has had an eating disorder, alcohol or drug addiction, or another mental health condition such as anxiety or depression
• Body dissatisfaction and internalization of socially-constructed ideas about what the so-called “ideal” body should look like
• Anxiety, low self-esteem, obsessive-compulsive disorder, or perfectionism
• A history of being criticized, teased, or bullied because of one's body weight, shape, or size
• A history of sexual abuse
  

Atypical Anorexia Nervosa Symptoms

In many cases, because there’s such a strong association between anorexia and low body weight, people with atypical anorexia are often overlooked. In addition, those who have atypical anorexia may point to their body weight to prove they aren’t sick.

However, there are a number of symptoms of atypical anorexia (and typical anorexia) that aren't based on an individual’s size or shape. These include:

• Excessive focus on body weight
• Fear of gaining weight or having fat
• Exercising excessively
• Weight impacts self-worth
• Preoccupation with food and a refusal to eat certain foods
• Refusing to eat socially
• Making excuses for not eating
• Increased irritability, mood swings, and other difficulties regulating emotions
• Difficulty concentrating

Although there is a lot of symptom overlap, it's worth noting that the DSM-5-TR (text revision) states that the physiological signs of anorexia and atypical anorexia aren't necessarily the same.

Consequences of Atypical Anorexia Nervosa

Because these symptoms are so often overlooked, those with atypical anorexia are often sicker for a longer period of time and are less likely to get the focused treatment they need.

Yet, due to the prolonged malnutrition people with atypical and classic anorexia experience, the medical consequences can be equally severe for both groups.

These consequences can impact every part of the body, and in some cases, affect the individual for the rest of their life. They include:

• Thinning hair or hair loss
• Yellow or dry skin
• Loss of bone mineral density potentially leading to osteoporosis (i.e., fragile bones)
• Menstrual irregularities in women, including the absence of periods
• Anemia (i.e., a low red blood cell count)
• Gastrointestinal issues such as dysphagia or acid reflux
• Constipation and abdominal pain
• Low heart rate or low blood pressure
• Lack of energy
• Anxiety, depression, or suicidality
• Death

Research has shown that adolescents with atypical anorexia who are overweight or have obesity are just as likely as those with anorexia to suffer from low heart rate and a rapid rise in heart rate when standing up.

The mortality rate among those with anorexia is six times higher than that of people without anorexia, and although there is less research on those with atypical anorexia, given the similar medical consequences, it’s likely the mortality rate for people with this condition is equally high.

Meanwhile, research shows that people with atypical anorexia often exhibit greater eating disorder psychopathology, including distress around body image and eating, than people with anorexia.

Atypical Anorexia Nervosa Treatment

The sooner someone with atypical anorexia nervosa seeks and receives treatment, the more likely they are to recover.

However, due to the perception that people of normal, overweight, or obese body weights cannot have eating disorders, it may be challenging to get the care they need.

Meanwhile, another study found that atypical anorexia occurs more frequently than anorexia, but those with atypical anorexia are less likely to be referred to and treated for their eating disorder.

Unfortunately, due to the lack of research on atypical anorexia, there are fewer guidelines on how to treat people with the condition.

Treatment Can Be Challenging

Treatment for those with atypical anorexia, especially those who are or used to be overweight or have obesity, may be especially challenging because the individual must physically recover from the malnutrition brought on by significant weight loss and psychologically recover from eating disorder psychopathology while also dealing with the medical complications associated with being overweight or having obesity.

It's essential that a doctor, clinician, or inpatient treatment program can prioritize, treat, and monitor each of these issues.

In order to ensure the best possible outcome, people experiencing symptoms of atypical anorexia should seek out healthcare professionals who specialize in eating disorders, adhere to Health at Every Size principles, and practice weight-inclusive care.

If you're experiencing symptoms that might indicate an eating disorder, it's important that you seek medical care right away. Also, a mental health professional can help you cope with any body image or self-esteem issues you may be feeling. Remember that you are not alone and recovery and healing are possible.