Doctors cannot diagnose an eating disorder with a single test or evaluation. Instead, eating disorders are diagnosed based on a combination of observed habits, tests, and symptoms. The American Psychiatric Association (APA) has established criteria that can help doctors diagnose an eating disorder. These criteria help doctors review signs, symptoms, and behaviors related to specific eating disorders.

To determine if you meet the APA’s criteria, your doctor will likely run a variety of tests and complete a full health profile. This may include asking your friends and family members about any unusual behaviors they have noticed. This step can help your doctor reach a diagnosis.

What Tests May Be Used to Diagnose an Eating Disorder?

A doctor may use several tests to help diagnose an eating disorder. These include:

A physical exam – To do a full physical exam, your doctor will check you from head to toe. He or she will check your height, weight, and body mass index (a measure of body fat). Your vital signs—heart rate, blood pressure, and temperature—will also be recorded.

Other physical symptoms of an eating disorder may be easily observed. These include dry skin, calluses or sores on the hands, swollen throat tissue, and dental decay.

Mental health history – Your doctor may ask you to complete a questionnaire. These questions will gauge your relationship with food, how often you eat, what you eat, and how you view your body. The purpose of these questions is to identify if there is a pattern of unhealthy thinking that may contribute to the eating disorder. Your doctor may ask friends and family members to fill out a similar questionnaire to better understand what they have observed.

In addition to the tests used specifically to diagnose an eating disorder, your doctor may also conduct a variety of tests and exams to check for any eating disorder–related complications. These tests may include:

Laboratory tests – Some physical side effects and complications of an eating disorder are easier to detect with a blood test. This test can detect levels of blood cells and electrolytes, as well as liver, thyroid, and kidney function.

Heart studies – An eating disorder can damage your heart. Your doctor may request a chest X-ray or electrocardiogram to see if the heart muscle has been damaged as a result of an eating disorder.

If you meet these diagnostic criteria for an eating disorder, your doctor will first treat any complications that may result from an eating disorder. They will also refer you to nutritionists and mental health professionals to address specific symptoms and help you overcome the eating disorder.