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Updated: Feb 14

It can be tricky knowing the different criteria for each eating disorder. We're often asked about the difference between bulimia nervosa and binge eating disorder.

This article will introduce you to both, and point out the differences between them.

An introduction to bulimia and binge eating disorder

What is Bulimia Nervosa?

Bulimia Nervosa includes episodes of binge eating, with purging behaviours or behaviour compensating for binges. These can be taking laxatives, over-exercising, and vomiting. There is also often a focus on body weight and shape.

You normally have to have had an episode once weekly or more over a three month period to be formally diagnosed.

What is Binge Eating Disorder?

Binge eating occurs repeatedly without any purging or compensating behaviours. Binge eating disorder differs from overeating. A binge eating episode may be eating faster than normal, until uncomfortable full, eating when not hungry or eating alone to avoid others.

Binging is often accompanied by disgust, guilt and or shame and a lack of control.

“It’s like a switch is turned on in your mind and the only thing you can do is eat until you physically cannot anymore.” - BED sufferer, BEAT UK

Why are bulimia and binge eating disorder often confused - and why can this be dangerous?

Both bulimia and binge eating disorder involve binging. Of the 1.25 million people in the UK with an eating disorder BED accounts for 22% of those cases and BN 19%.

They share a lot of underlying risk factors and some symptoms but require specific treatments so shouldn’t be confused, the sooner you get a correct diagnosis the quicker you can be put on the right path to recovery.

Please note that you don’t need to have a diagnosis to seek private support (such as with us at Ease Nutrition Therapy). A diagnosis might be helpful for some people, and unhelpful for others.

Being diagnosed as having BED but feeling like you don’t fit the criteria can feel isolating, knowing more about the eating disorder you are experiencing and how to get the right support is crucial.

You never want to feel ‘not sick enough’ to have an eating disorder, or meet the criteria for one.

Signs of Binge Eating Disorder

  • Mood:

  1. Low confidence and self-esteem: either as a trigger for binging or as a result - or both.

  2. A lot of time is spent thinking about food, this might be out of your control.

  3. Sleeping is difficult leading to tiredness and lack of concentration.

  4. Social withdrawal can happen either due to guilt or anxiety around binging or wanting to eat in private.

  • Body changes:

  1. Might be associated with weight gain. However, not everyone who binge eats is in a larger body.

  2. Stomach pain and problems can occur.

  3. Bloating, diarrhoea, and constipaiton.

  • Eating behaviour:

  1. Buying a large amount of food is common, especially certain foods to binge on. Such foods may be foods that are otherwise restricted or seen as ‘treat’ foods.

  2. Food may be hoarded to be consumed during a binge. This may be completely out of the person’s control, or feel like it is.

  3. Periods where restriction is higher and binging is lower.

Signs of Bulimia Nervosa

  • Focus on body image:

  1. Either frequent checking your body shape and weight. Or avoiding looking at your body/weight.

  2. Comparing your body to others often.

  3. Fear of gaining weight.

  • Mood:

  1. Mood swings and irritability often occur, sometimes as a result of rapidly changing blood sugar due to bingeing and purging.

  2. Around meal times anxiety will majorly increase, especially if eating as part of a group.

  3. May have difficulty concentrating either due to focus on food or lowered blood sugar.

  4. Difficulty sleeping can lead to extreme tiredness.

  • Eating:

  1. Food often eaten in secret, large amounts hoarded for binges.

  2. If eating in a social situation such as a family meal, sufferers will often disappear quickly after eating in order to purge.

  3. Periods where restriction is higher and binging is lower.

  • Body changes:

  1. Due to purging, stomach problems often occur. Such as bloating, stomach pain and constipation.

  2. Periods may either be irregular or stop.

  3. If vomiting is used as a purging mechanism there can be damage to the teeth, back of the hands and the glands that produce saliva might be swollen. If this continues long term the throat and vocal chords might be damaged by stomach acid.

  • Other aspects of life:

  1. Social withdrawal often occurs as eating is done alone

  2. Sometimes those suffering from bulimia might misuse alcohol

  3. May be a lack of sexual interest.

  4. Life may be organised around opportunities to binge and purge e.g. not going too far away from home or somewhere purging can occur.

What are the differences between bulimia and binge eating disorder?

1. Purging (compensating): Although self-induced vomiting is the most commonly known form of purging. Those suffering with bulimia may use laxatives, over exercise or use diet pills, and diuretics.

Some classify BN into purging and non-purging, with non-purging relating to behaviours such as fasting, skipping meals, overexercising, using stimulant drugs and using diet pills - this can still be seen as purging, but not direct vomiting.

Those experiencing binge eating disorder do not purge. Although they may diet and then restrict their intake post binge in order to ‘compensate’ for the increased intake this isn’t diagnostically classed as purging.

2. Main triggers: For those suffering from BED the main trigger tends to be emotional, whether through a situational change or reacting to a change in situation that is thought to be overwhelming. Often bingeing might occur due to emotional eating or wanting ‘comfort foods’ as a way to deal with this.

In contrast for those experiencing bulimia nervosa it may commonly be triggered by ‘failing’ a diet or form of restriction. This often causes the ‘all or nothing’ response. We feel we’ve fallen off the wagon and so might as well binge eat quite a lot of food because what the hell. After binging guilt and / or shame might kick in, and so purging is used to help compensate.

It may be that the first time we promise that this is the only time, but the diet cycle is doomed to fail, and after the next failure bingeing and purging might happen again.

3. Body Image concerns: If you experience bulimia nervosa body image concerns may play a major role in your life. This might be constantly comparing your body to those around you, people on social media or even your body as it looked at another time.

This is often accompanied by a fear of gaining weight regardless of where your body weight currently sits. This may mean you constantly check your weight on a scale or how it looks in the mirror – or you avoid the mirror and scale altogether because it makes you anxious.

Currently, with binge eating disorder body image concerns is not currently used to help with diagnosis or mentioned as a key symptom. Although, those experiencing BED might start restricting or dieting in response to binge eating episodes.

Entering into diet culture might induce body image worries and comparison with others. So, don’t feel like a pretender if you’re experiencing BED but find yourself constantly worrying about how you look or what you weigh.

4. Side effects: Binge eating disorder causes less long-term side effects than bulimia. This may be due to the absence of purging behaviours. Often the most common side effects tend to be related to the overloading of the stomach, which can lead to gastrointestinal issues. In the short term this includes abdominal pain and feelings of bloating, but long term IBS can manifest and the gut may even be perforated.

In BN, dependent on the purging behaviours side effects may vary but some include:

  • Long term effects on the throat and vocal chords if vomiting is self-induced, including potential rupturing or tearing of the oesophagus.

  • Long term effects on the stomach due to laxative abuse – for more information see our article on laxative abuse here.

  • Frequent purging can cause dehydration and an electrolyte imbalance, this can then lead to some further side effects on the heart.

5. Diagnosis migration: When diagnosed with an eating disorder, many individuals might change diagnosis over the course of their experience, sometimes called diagnostic flux or diagnosis migration.

Bulimia Nervosa can sometimes migrate to BED as purging mechanisms reduce. Often those experiencing BN may have also migrated from anorexia nervosa (AN) as they start to increase their intake from a place of severe restriction.

6. Recovery time: Binge eating disorder has a shorter recovery time than bulimia, and 70% of those entering recovery report fully recovering. In contrast 20% of those with BN report fully recovering. It can be hard to quantify a recovery time for any eating disorder, as recovery is not always straightforward and many people experience relapses before fully recovering.

7. Treatment options: Self help approaches are thought to be effective for BED but not BN

In binge eating disorder your first point of treatment may be guided self-help. This may include self-help books and guides which allow you to monitor what you eat, make meal plans and try and identify triggers for you. This may be accompanied by a self-help support group. As binge eating disorder often occurs with anxiety and depression so antidepressants may be prescribed.

With bulimia, you may also be offered a self-help course of treatment but this isn’t as useful as with binge eating disorder. CBT is often prescribed, with around 20 sessions over 20 weeks being prescribed in the UK. Interpersonal therapy and family therapy may also be offered. If symptoms are severe bulimia may be treated in a hospital environment.

Summary of the differences and similarities between bulimia nervosa and binge eating disorder:

​Binge eating disorder (BED)

Bulimia nervosa (BN)


No - unless dieting and periods of restriction are counted as purging

Yes - vomitting, laxative and diuretics use, over-exercising

Main triggers

​Sudden change in mood, coping with a situation change.

Diet failure - breaking a self imposed food rule. ‘What-the-hell-effect’

Body image

​No diagnostic criteria

Presence of focus on body weight and shape

Diagnosis migration

Not thoroughly researched. But from clinical experience, people with BED tend to have had a history of AN and/or BN