Similarities Among Restrictive Eating Disorders

Research Study at the Massachusetts General Hospital
Eating Disorders Clinical and Research Program

When most people hear the term “restrictive eating disorder,” they probably think of anorexia nervosa (AN). But there are other eating disorders beside AN that involve either limiting food intake, or trying to avoid it entirely. Our team at Massachusetts General Hospital (MGH) is currently carrying out a study, to understand the thoughts, feelings, and behaviors, of individuals with restrictive eating disorders and to see how these are related to brain functioning and hormone levels. The overall goal is to understand what restrictive eating disorders have in common, what distinguishes them, and how underlying similarities might help clinicians develop new treatments.

Restrictive Eating Disorders – Not Just Anorexia Nervosa

Restrictive eating is the core symptom of a wide variety of feeding and eating disorders. Here are just a few examples:

Anorexia Nervosa (AN). AN is an eating disorder characterized by food restriction and body image disturbance. Individuals with AN also describe an intense fear of gaining weight or engage in behaviors such as under-eating, compulsively exercising, or purging – that prevent them from gaining weight, even though they are underweight. Those with AN often have a distorted view of their body and appearance, judge their self-worth mostly on their body shape and weight, and/or are unable to recognize the seriousness of their low weight. Interestingly, AN is probably the rarest eating disorder in the general population, despite being the best known.

Atypical Anorexia Nervosa. Some individuals have food restriction, body image disturbance, and fear of weight gain even though they are not underweight. Although these individuals do not meet criteria for AN as defined by the Diagnostic and Statistical Manual of Mental Disorders 5th edition (DSM-5), they still have an eating disorder. As discussed in Dr. Thomas’s book Almost Anorexic: Is My (Or My Loved One’s) Relationship with Food a Problem?, atypical AN can be just as severe as full-syndrome AN in the areas of eating pathology, physical complications and other mental health problems (e.g. anxiety, depression), and is equally deserving of recognition and treatment.

Avoidant/Restrictive Food Intake Disorder (ARFID) is newly included in DSM-5 and describes individuals who have difficulty meeting their nutritional or energy needs without co-occurring weight and shape concerns. Thus, individuals with ARFID may be underweight like those with AN, but they also may be normal weight or overweight. A key difference between those with ARFID and AN is that those with ARFID do not worry about gaining weight. Individuals who meet criteria for this disorder may limit the amount of food they eat or the types of foods they consume because they have a low appetite and do not feel hungry, find the textures or tastes of certain foods are very intense or unpleasant, or feel afraid of choking or vomiting.

Dangerous Consequences of Restrictive Eating Disorders

All three of these restrictive eating disorders are very serious mental and physical illnesses. Families can feel powerless to help their loved one. Some individuals must put their lives on hold (either to engage in disordered eating behaviors or access much-needed treatment), and many feel isolated from friends and family. In addition and most frighteningly, more people die per year from (AN) than from any other psychiatric illness. Various reasons account for lethality of this condition including psychological disturbances like depression and suicidality and dangerous medical complications associated with low weight and starvation (e.g., heart failure). Because these medical problems are associated with low weight and undernourishment, they can also impact individuals with ARFID and atypical AN. Although 22-year outcome data from our team at MGH suggests that the majority of people with AN do recover with time, some individuals develop a chronic form of illness Moreover, no evidence-based treatments exist for ARFID at present.

Searching for the Causes and Maintaining Mechanisms of Restrictive Eating Disorders

Our team at MGH is interested in understanding more about what causes and maintains low weight eating disorders. For instance, why do some people develop an eating disorder, while some don’t, even though their life circumstances may be very similar? Are there biological differences in the brain that make some people more susceptible? Why do some people have AN, atypical AN, or ARIFD for a long time, while others recover quickly? Why is it that some people who are underweight restrict their eating entirely, while others engage in bingeing and purging? Ultimately, we believe that finding the answers to these questions help improve treatment and outcome for individuals affected by these disorders and their families.

That’s why our team is currently in its second year of a five-year longitudinal study of adolescent females with restrictive eating disorders. The study, led by MGH investigators Drs. Madhu Misra, Elizabeth Lawson, and Kamryn Eddy, is funded by the National Institute of Mental Health. The study has two main goals: The first is to examine two types of food motivation pathways in the brain: regulatory pathways and reward pathways. Regulatory pathways function to help the body balance hunger and fullness cues so that an individual can maintain a healthy level of food intake. These are the cues that help us to eat when we are hungry, and stop when we are full. In contrast, reward pathways involve the amount of pleasure people experience when eating. Consistent with the adage that “there’s always room for dessert!”, reward pathways are activated when an individual experiences a particular food as pleasurable, regardless of whether the body is experiencing hunger. Different people find different foods pleasurable and people also differ in how much pleasure they receive from eating their favorite foods. The study seeks to discover whether individuals with restrictive eating disorders have greater difficulty recognizing hunger and perhaps find food less rewarding, in comparison to individuals without eating disorders.

Adolescence is an important time of rapid growth and transition, making it a high-risk period for the development of eating disorders. Fortunately, research has shown that early detection and treatment is a strong predictor of making a full recovery from restrictive eating disorders. Because the study uses a longitudinal design, we follow our participants over 18 months, and hope to determine whether regulatory and reward pathways normalize with weight recovery, and/or predict longstanding difficulties with restrictive eating.

Participant Recruitment is Key to Developing Findings

One of the most exciting and rewarding parts about conducting the study is interacting with participants. Our participants range from 10-21 years old, and all share an interest in contributing to science and helping others who also have an eating disorder. Participating in research is a way for them to give back and to feel connected to a prevention and treatment cause. Many participants – even those struggling in their own recovery – say that they hope no one else has to go through the same suffering they have endured.

Study coordinator, Chris Mancuso, monitors an fMRI scan in progress.

Participating in a research study can also be meaningful for individuals without a disorder. We also recruit healthy volunteers, who don’t have AN or ARFID, to participate in our studies as the healthy comparison by which we compare those with an eating disorder. Without this valuable information, we would not be able to start answering questions related to neurobiological vulnerabilities to eating disorders or neurobiological changes that occur during the course of the illness.

While healthy volunteers may not have a personal connection with the disorder itself, they report enjoying being a part of the scientific process. Many volunteers have interest in pursuing science as a career, and enjoy experiencing research firsthand. Sometimes, potential research participants who express interest in being a healthy volunteer realize that they are struggling with mental health issues of their own throughout the course of the screening process. For example, after completing the questionnaires and speaking to study staff during the clinical interview, they may become aware of behaviors, thoughts, or feelings that they did not know where dangerous or problematic for their physical and/or mental health. Thus, participating as a healthy control can increase insight and self-awareness. If this occurs in our studies, we provide participants with resources and encourage and support them in seeking help that they might not otherwise have sought.

Interested in Participating?

Participants in our research study attend a screening visit and 3 main study visits. The screening visit involves a medical examination that includes an x-ray scan. The main study visits each involve a series of questionnaires and computer tasks to assess symptoms and various different thinking styles. The main visits also includes brain scans using functional magnetic resonance imaging (fMRI) to observe how the brain responds in certain tasks and when certain pathways are active. If they are interested, participants are welcome to take home a picture of their brain.

The research team at MGH is delighted to be working with our participants to answer important questions about the progression and neurobiological features of restrictive eating disorders while also identifying new questions to ask. Our hope is that this work will reveal important information regarding the diagnosis and classification of disordered eating and will help improve treatments for these conditions.

If you will be in the Boston area and might be interested in participating in our study, we would be happy to share more information with you. To contact us, please email, or complete an online screening form.

Follow this link to learn more about other study participation opportunities in eating disorders at MGH.

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Additional Reading:

To learn more about restrictive type eating disorders that do not meet criteria for AN or ARFID, check out Dr. Thomas’s book, Almost Anorexic.

About The Authors:

By Kathryn Coniglio B.A., Kendra Becker M.S., and Jennifer J. Thomas, Ph.D., Eating Disorders Clinical and Research Program, Massachusetts General Hospital.


Thomas JJ, Schaefer J. Almost Anorexic: Is My (Or My Loved One’s) Relationship with Food a Problem? Center City, MN: Hazelden/Harvard Health Publications; 2013.
Keshaviah A, Edkins K, Hastings E, Krishna M, Franko DL, Herzog DB, Thomas JJ, Murray HB, Eddy KT. Re-examining premature mortality in anorexia nervosa: A meta-analysis redux. Compr Psychiatry 2014; 55: 1773-84

Mehler, P. S., & Brown, C. (2015). Anorexia nervosa–medical complications. Journal of eating disorders, 3(1), 11.

Eddy KT, Tabri N, Thomas JJ, Murray HB, Keshaviah A, Hastings E, Edkins K, Krishna M, Herzog DB, Keel PK, Franko DL. Recovery from anorexia and bulimia at 22-year follow up. J Clin Psychiatry. In press.

Written – 2016