Dual Diagnosis & Co-Occurring Disorders

It is not uncommon for those with an eating disorder to struggle with other mental health diagnoses as well. The direction of this relationship is unclear and depends on each individual. Eating disorders may develop as maladaptive coping skills for mental health diagnoses, however, mental health issues may also develop as a result of eating disorder behaviors. Regardless, understanding the relationship between eating disorders and co-occurring mental health issues is key to effective diagnosis and treatment of the individual.

What is an Eating Disorder with a Co-Occurring Disorder?

Co-occurring disorders refer to individuals that struggle with two or more mental health diagnoses at once. For those with eating disorders, this means that they engage in and struggle to overcome eating disorder behaviors in addition to other existing mental health disorder(s).

Approximately 56.2% of those with Anorexia Nervosa, 94.5% of those with Bulimia Nervosa, and 78.9% of those with Binge Eating Disorder (BED) meet criteria for at least one other mental health diagnosis [1].

One study that looked at 2400 individuals found that 94% of those hospitalized for eating disorders also had a mental health mood disorder [2].

mental health graphic

Mental Illnesses Associated with Eating Disorders

The most common co-occurring disorders with eating disorders are detailed below and how the existence of each of these can impact eating disorder symptomatology and treatment differs depending on diagnosis and presentation.

Anxiety Disorder

Anxiety Disorders may well be the most common co-occurring mental health diagnosis with eating disorders. Approximately 47.9 & of those with Anorexia Nervosa, 80.6% of those with Bulimia Nervosa, and 65.1% of those with BED also struggle with an anxiety disorder diagnosis such as Generalized Anxiety Disorder (GAD), Panic Disorder, Phobias, and Separation Anxiety, to name a few [1]. The risk factors for both of these disorders are similar, as both tend to be experienced by individuals that struggle with rigidity in their beliefs and behaviors as well as those with neurotic or perfectionist tendencies. As mentioned above, regardless of which disorder “came first,” they often build on one another and must be treated simultaneously.

anxiety mental health graphic

Learn More About Anxiety and Eating Disorders

Mood Disorders

Like anxiety disorders, depression and other mood disorders (such as Bipolar Disorder) often co-occur with eating disorders. These disorders often lead to the development of eating disorders as an ineffective method of coping, occur due to malnourishment and the impact of eating disorders, and/or both. 42.1% of those with Anorexia Nervosa, 70.7% of those with Bulimia Nervosa, and 46.4% of those with BED also have a diagnosis of a depressive disorder.

Learn More About Depression and Eating Disorders

Girl with Bipolar

Borderline Personality Disorder (BPD)

Approximately 14 to 53% of those with BPD also experience an eating disorder diagnosis [3]. BPD differs from any other disorder listed as it falls under the Diagnostic and Statistical Manual of Mental Illness (DSM-5) criteria for personality disorders. These refer to long-term patterns of thoughts and behaviors that are more chronic versions of mental illness than an anxiety or mood disorder, for example. Those with both BPD and eating disorders struggle with emotional regulation, distress tolerance, interpersonal effectiveness skills, and grounding themselves. Individuals with BPD also engage in severe behaviors to avoid real or perceived rejection and these behaviors, with some of these being eating disorder behaviors.

Learn More About BPD and Eating Disorders

Obsessive Compulsive Disorder (OCD)

Similar to anxiety disorders, the traits that put one at risk for eating disorder development also put one at risk for development of OCD. These include attachment to rigidity, meticulousness, or perfectionism as well as difficulty coping with distress related to daily life changes, big or small. Eating disorders often involve both obsessive beliefs and thought patterns as well as compulsive behaviors. Research indicates that “those with eating disorders have significantly higher rates of OCD” development [4].”

Learn More About OCD and Eating Disorders

Post-Traumatic Stress Disorder (PTSD)

Trauma severely impacts the psychological, neurological, and sociological functioning of individuals that experience it. The relationship between trauma experiences are linked with all eating disorder diagnoses, yet, appears particularly significant in those with Bulimia Nervosa. One study noted that “eating disordered behaviors, particularly purging behaviors, serve to facilitate avoidance of traumatic material and to numb the hyperarousal and emotional pain associated with traumatic memories and thoughts [5].” Additionally, those with a PTSD diagnosis tend to experience an increased disconnect from the body and emotions as well as dissociative states, all of which can also contribute to eating disorder development.

Learn More About PTSD and Disordered Eating

Related Reading


Self-harming behaviors are frighteningly common in those with eating disorders, with 61% of those that report engaging in self-injurious behaviors also reporting current or past eating disorder behaviors [6]. Self-injury refers to any behaviors in which an individual physically harms themselves. Those with eating disorders often develop this behavior as an ineffective coping skill for uncomfortable mood-states. For some, the eating disorder behaviors themselves are intended to be self-harming.

Learn More About Self-Injury and Eating Disorders


Trichotillomania falls under the DSM-5 category of “Obsessive-Compulsive Related Disorders” and refers to an individual experiencing a compulsive need to pull out one’s hair. Individuals with eating disorders and trichotillomania share many clinical features such as emotion dysregulation, an inability to effectively cope, and/or obsessive-compulsive tendencies.

Substance Use Disorder

Substance use disorders are incredibly common in those with eating disorder diagnoses, with 27% of those with Anorexia Nervosa, 36.8% of those with Bulimia Nervosa, and 23.3% of those with BED experiencing both [1]. These disorders often feed off of one another, with one study determining that women with either an eating disorder or substance were more than 4 times as likely to develop the other disorder as those women that experienced neither disorder [7]. People often use substances and/or eating disorder behaviors to help them cope and, therefore, those struggling are likely to engage in one or both disorders.

substance abuse mental health graphic

Learn More About Substance Abuse and Eating Disorders


The relationship between alcoholism and eating disorders is included in much of the research on substance use disorder and eating disorders mentioned above. Excessive alcohol use is often seen as a method to numb from uncomfortable emotion-states as well as reinforce, or cause, eating disorder behaviors such as purging or restricting.

Learn More About Alcoholism and Eating Disorders

Finding Dual-Diagnosis Treatment Centers

Regardless of the diagnosis, research indicates that rates of long-term recovery are more likely if any co-occurring disorders are treated simultaneously alongside the eating disorder. Most treatment centers hire professionals that are educated in treating co-occurring disorders due to how commonly they exist alongside eating disorder behaviors. Additionally, treatment centers will often screen for other mental disorders. If you are aware that you struggle with a co-occurring diagnosis along with your eating disorder behaviors, do not be afraid to ask any potential treatment centers or professionals of their experience or capabilities in treating your disorders.

mental health treatment graphic


  • [1] Unknown (2017). Eating disorders. National Institute of Mental Health. Retrieved from https://www.nimh.nih.gov/health/statistics/eating-disorders#part_155062.
  • [2] NEDA (2022) Anxiety, Depression, and Obsessive Compulsive Disorder. Retrieved from https://www.nationaleatingdisorders.org/anxiety-depression-obsessive-compulsive-disorder
  • [3] Khosravi, M. (2020). Eating disorders among patients with borderline personality disorders: understanding the prevalence and psychopathology. Journal of Eating Disorders, 8:38.
  • [4] Neziroglu, F., Sandler, J. (2009). The relationship between eating disorders and OCD, part of the spectrum. The OCD Newsletter. Retrieved from https://iocdf.org/expert-opinions/expert-opinion-eating-disorders-and-ocd/.
  • [5] Brewerton, T. D. (2008). The links between PTSD and eating disorders. Psychiatric Times.
  • [6] Levitt, J. L., Sansone, R. A., Cohn, L. (2008). Self-harm behavior and eating disorders. Bruner-Routledge. New York,. NY.
  • [7] Unknown (2011). Clients with substance use and eating disorders. Substance Abuse and Mental Health Services Administration, retrieved from https://store.samhsa.gov/sites/default/files/d7/priv/sma10-4617.pdf.

Author: Margot Rittenhouse, MS, LPC, NCC

Last Reviewed By: Jacquelyn Ekern, MS, LPC on August 30, 2021

Page last updated: August 17th, 2021
Published on EatingDisorderHope.com