GLP-1 and eating disorders: risks and screening

Why screen before starting treatment?

An international expert consensus published in World Psychiatry recommends asking everyone about a current or past eating disorder before prescribing a GLP-1 medicine [1]. It suggests using a brief questionnaire of three to five questions in any consultation where the medicine is prescribed, including primary care [1].

These questions are a way to start a conversation. If any concerns emerge, they can lead to a fuller assessment with mental health services, and the findings may affect whether treatment is recommended or how often reviews take place. It is therefore helpful to answer them calmly and honestly, even if the eating disorder was a long time ago.

If you are prescribed the medicine without being asked about this, you can raise it yourself. You only need to say whether you have had difficulties with food and when. At the first appointment, you do not need to share more detail than you are comfortable with.

Why might things be different with a history of an eating disorder?

The medicine reduces appetite and the desire to eat. For someone who has experienced an eating disorder involving restriction, this effect may reinforce familiar patterns. This applies to semaglutide (Ozempic, Wegovy) and tirzepatide (Mounjaro), as all three brands affect appetite in a similar way.

An analysis of 25 trials found that these medicines moderately reduced binge eating and the feeling of being out of control around food [2]. At the same time, they increased cognitive restraint, meaning deliberate control over how much and what a person eats [2]. The trials had limitations, and better studies are needed [2].

This kind of control may help someone eat less. For someone who has experienced anorexia or bulimia, it is precisely what needs monitoring. For this reason, the consensus generally recommends not using these medicines when an eating disorder is active, particularly anorexia, atypical anorexia or bulimia involving substantial restriction [1]. If you have a past history, it advises caution even if you feel you have recovered [1].

What we see in consultations

We ask everyone starting a GLP-1 medicine about their eating history, including those who do not mention one. It can be difficult to talk about. People may worry that a treatment that is finally helping with their weight will be stopped, or feel embarrassed about discussing something they thought was behind them.

We also see people who are already taking the medicine and notice that they are controlling food more rigidly than before. It is helpful to mention this early, without waiting for it to get worse. The sooner it is discussed, the easier it is to adjust the support.

Another common situation is someone with no history of an eating disorder who starts to feel guilty about eating, even when they are eating reasonable amounts. In these cases, we explain that having less appetite while taking the medicine is expected, and that eating what your body needs remains part of treatment, without turning every meal into a test.

What does ‘monitor closely’ mean if you have recovered?

A past eating disorder that has resolved does not mean there is no risk. The consensus recommends closer monitoring, without ruling out treatment automatically [1]. In practice, this means more frequent reviews at first and direct questions about your relationship with food, as well as your weight.

Starting a GLP-1 medicine when you have a past history is a shared decision. You, the person prescribing the medicine and, if possible, the person who treated your eating disorder make the decision together. If you would like support with your relationship with food while you decide, you can do this through our psychonutrition service.

How nutritional care changes if you have a past history

If you have a history of an eating disorder, we will agree a regular and adequate eating plan with you and the specialist team, tailored to your needs and without rigid calorie targets or lists of forbidden foods.

Your weight is checked in appointments when appropriate, and we also talk about your energy, strength, sleep and how you feel when eating. If you are receiving psychological care, nutritional support is coordinated with it and follows its pace.

If signs of an eating disorder emerge

If signs of an eating disorder emerge, we offer you a specialist assessment without waiting for your next review, and coordinate nutritional care with psychology and the person prescribing your treatment.

We explain how this fits into the wider support in our guide to GLP-1 medicines.

Can a GLP-1 medicine help with binge-eating disorder?

At present, no GLP-1 medicine is approved to treat binge-eating disorder. An analysis of 25 trials found fewer binge-eating episodes with these medicines, particularly in studies involving people with a diagnosis, although the trials were of limited quality [2]. A small trial of liraglutide found no difference from placebo in binge-eating episodes, although weight loss was greater [3].

The consensus calls for more trials before recommending this approach and, where an eating disorder has been diagnosed, for psychotherapy alongside the medicine [1]. If you experience binge eating, psychological treatment remains the main approach; your doctor decides whether to use medicine.

Can a GLP-1 medicine cause an eating disorder?

How often this happens is not known. Experts consider it possible and recommend monitoring for it, particularly in people who have had an eating disorder before [1]. Most people starting treatment have no such history, and screening helps identify those in a different situation.

In a survey of adults in the United States with an eating disorder, one in three had used a GLP-1 medicine at some point [4]. One in ten had misused one [4]. These figures apply to that specific population and cannot be applied to people starting treatment with no previous history.

Screening helps ensure that someone also pays attention to your relationship with food while you are having treatment.