Is fasting an eating disorder?

What is fasting?

Fasting is a type of behavior that involves refraining from food and sometimes liquid for extended periods.

One may participate in this type of behavior for many reasons, including religious observations and medical concerns. (Some medical tests require someone to refrain from eating for several hours.)

But fasting to encourage weight loss—sometimes called intermittent fasting—has become an increasing trend in recent years. People may fast on alternating days, for certain portions of the day, or fast following a large meal, whether as part of an overall diet plan or on a more intuitive basis.¹

Is fasting an eating disorder?

Fasting often represents disordered eating behavior, and while it may contribute to developing an eating disorder, the action in itself is not an eating disorder.

Eating disorders are technically considered behavioral conditions or mental health disorders. They involve disturbed behaviors and actions and repeated, disturbed, or distressing thoughts.²

Things like disturbed body image, low self-esteem, trauma, and even a desire to be "healthy" may drive interest in fasting for losing weight. However, fasting alone does not represent the suite of psychological concerns at play in an eating disorder. The behavior can be more accurately described as a symptom of an eating disorder.

Can fasting cause an eating disorder?

None of this is to say that fasting can't be dangerous or be part of a slippery slope.

When used to help control weight, the behavior can be (but isn't always) indicative of an unhealthy relationship with food or a fixation on body image. These are often hallmark signs of an eating disorder or potentially correlated behaviors.⁵

It's also plausible that someone would experiment with fasting or intermittent fasting before moving toward more disordered behavior. Consistent dieting behavior has long been noted as a precursor to eating disorders.³ Studies have shown that intermittent fasting, in particular, is linked to higher levels of eating disorder psychopathology.⁶

Still, more likely than cause an eating disorder, fasting to help control food intake or weight may serve as an indicator that someone is already dealing with an eating disorder or the types of thoughts that lead to one. Fasting is among the eating disorder behaviors often used by people struggling with AN and BN.

Signs fasting is leading to an eating disorder

The line separating fasting from an eating disorder can quickly become blurry. It's important to monitor your habits or those of your loved one, for additional signs of an eating disorder or any of these warning signs:

Fasting also has the potential to lead to binge eating behavior. Many people experience a strong urge to overeat following periods of fasting.¹ This can cause people to engage in a binge eating episode, then turn to fasting—or other behaviors—to compensate for the binge, kicking off an unhealthy eating pattern of binging and purging.

Is fasting dangerous?

Fasting to lose weight is still a relatively new phenomenon. In light of the intermittent fasting trend, the behavior is being looked at with a closer eye to health. While studies are ongoing, and some potential health benefits have been identified, some reports have noted a few potential dangers around the behavior.

Research has shown that fasting may cause gallstone issues for some people.⁴ Intermittent fasting can also be problematic for people with diabetes due to its impact on blood sugar levels, resting metabolism, and other related issues.

In fact, due to these potential concerns, intermittent fasting diets are not recommended for those with diabetes or people who take medicine for blood pressure or heart disease.¹

Getting treatment for a restrictive eating disorder

If you're concerned about your behavior or that of a loved one, reaching out to a professional who can offer more guidance is important.

Filling out an eating disorder examination questionnaire can help a doctor or therapist determine whether your fasting behaviors have become dangerous or are presenting as part of a deeper problem.

Regardless, anytime someone becomes fixated on losing weight, experiences frequent distress over their body shape or size, or starts resorting to increasingly extreme behavior to achieve their weight loss goals, it's often worth examining the situation further.

Contacting a professional can be the first step toward building a healthier relationship with food, your body, and yourself and starting on a path toward a happier future.