Anorexia, bulimia, binge eating: how they differ

“So — which one of these do I have?”

That question usually arrives at the second or third session, once someone has already said enough that saying this too is no longer frightening. And it is a fair question. The names are in circulation, there are tonnes of them online, but most explanations describe mainly what a person does. That part is the least useful and most often the most harmful — because to a reader with an eating disorder it becomes a benchmark rather than an explanation.

So in this piece I will describe the differences another way: through how each picture is experienced from the inside. What the relationship to the disorder is like, what dominates the mind, who notices first, what helps. No numbers and no descriptions of behaviour, because nobody needs those.

What the names are for

A diagnosis is not a description of a person. It is a working agreement within the field about which group of difficulties behaves similarly and responds similarly to treatment. It is useful so that someone knows what to suggest and what not to. It becomes useless the moment it turns into an identity card.

I have written about this in the piece on how a diagnosis is a map and not a name. With eating disorders this holds even more than elsewhere, because people often use the name as proof that they are not ill enough. “But I don’t have anorexia” is one of the most common reasons someone postpones help for years. A formal diagnosis is made by a doctor or a clinical psychologist — I have set out who does what in the piece on who may diagnose.

What all three share

Underneath all three pictures lies the same axis: self-worth has become dependent on how things go with food, with the body, and with mastering both. This is the core described by Christopher Fairburn, and today it is the basis for treatment that works across all three pictures.

Something else is shared too. All three escalate in secrecy. All three function as a way of handling states a person otherwise cannot tolerate. And in all three the rules tighten over time while life shrinks around them. The differences I describe below are differences in the pattern of experience — not in who is the more serious case.

Anorexia nervosa: a disorder experienced as an ally

The most particular feature of anorexia is that for a long time it does not feel like a problem but like a solution. The field calls this ego-syntonicity: the disorder is aligned with what the person believes they ought to be. It provides structure, a sense of achievement and a calm that is not available elsewhere.

So with anorexia it is typical that others register the distress first, while the person experiences their concern as interference. This is not denial in the sense of lying. It is that a starved brain thinks more rigidly, more narrowly and in more black-and-white terms — and in that state any suggestion of change looks like a threat to the only thing holding everything together.

Anorexia is also the picture in which physical risk is highest and medical assessment most urgent. This is not a statistic I am going to unpack here; it is the reason not to wait when there is a suspicion.

In practice this means that with anorexia a therapist never works alone. At minimum there has to be a link with the person’s GP, and with adolescents also with a specialist service. When someone comes to me hoping to sort this out through conversation alone, I say so straight away — not to turn them away, but because promising otherwise would be dishonest.

Bulimia nervosa: a disorder experienced as an enemy

With bulimia the relationship is precisely the opposite. Almost nobody experiences it as a solution. People describe it as something that happens to them although they do not want it — a cycle that fires when distress runs too high and leaves regret and self-disgust behind.

This ego-dystonicity has two consequences. The first is good: motivation for change is often greater from the outset, so bulimia typically responds to treatment faster than anorexia. The second is bad: the shame runs deeper, so it stays hidden for longer. People with bulimia often appear tidy, productive and pleasant while something nobody knows about is going on underneath. I have written separately about this kind of shame that speaks about a person rather than a deed.

Binge eating disorder: the commonest and the least acknowledged

Binge eating disorder only entered the official classifications in 2013, although of the three it is the most common. It is experienced above all as a loss of contact with oneself — a period in which a person feels absent, and then “wakes” into a strong sense of guilt.

Because there are no marked outward signs that others would attribute to a disorder, people often fail to get acknowledgement even from themselves. Instead they spend years treating it with new diets, which as a rule makes things worse — tightened rules increase the likelihood of the next episode. Very often depression, anxiety or unprocessed traumatic experience sit alongside it.

With this picture, what interests me most in therapy is what was happening in the hours before an episode. Almost always the same pattern shows up: a day in which the person forgot themselves — did not eat, did not rest, did not say no, had not a minute for themselves. The episode is then not a sign of too little discipline but the closing of a day that held too much of it. For many people this is an entirely new explanation, and often the first moment when shame steps back a little.

The boundaries between them are not sharp

If I had one sentence for this piece, it would be this: these three pictures are not three separate illnesses but three positions of the same problem, and people move between them over the years. Studies that followed people over longer periods show that a considerable proportion of those with one picture later fit the description of another. The most common direction is from restriction towards the cycle, and less often the other way.

So the question “which one do I have” matters less than it seems. The more important question is which rules currently run my day, and what happens when I break them. Besides, the largest diagnostic group in eating disorders is the one that does not fully fit any box — in the classifications it is called other specified feeding or eating disorder. Those people are not less ill. They are only less recognisable.

What I ask instead of “which one do you have”

In practice I have a few questions that tell me far more than a category. The first is how much of the day is taken up by thoughts about food and the body — not whether they are present, but whether anything else has room left. The second is what happens when a rule is broken: if a whole day of correcting, punishing or withdrawing follows, that is a message in itself.

The third question is social. Have you given up something that used to matter to you — a trip, dinner with friends, a visit to your grandmother. Eating disorders are almost always visible in how a calendar empties. And the fourth: who knows about it. The answer “nobody” is more important information than any label, because it says how long someone has carried alone a thing that only grows stronger in solitude.

Why the name changes treatment anyway

If the boundaries are not sharp, why distinguish at all? Because the first steps differ.

For adolescents with anorexia the recommended first choice is family-based treatment, in which parents take an active role in establishing nutritional stability. For bulimia and binge eating in adults, psychotherapy adapted to eating disorders has better support — work that addresses mainly the rules and the factors maintaining the cycle in the present. With anorexia, concurrent medical monitoring is always needed as well; with the other two it depends on the person’s condition.

In short: the name does not say who you are. It says which end it makes most sense to start from.

Where this division misleads

Now the part that unsettles my own piece. Dividing things into three pictures has some serious drawbacks and it would not be fair to leave them out.

The first: people picture each category by outward appearance rather than by experience. Which means that a great many people with a serious disorder whose appearance does not match expectation go untreated for a long time — although they may be just as at risk physically and mentally. Research on so-called atypical forms shows this clearly. Appearance is not a measure of severity and never was.

The second: this division grew up historically around young women and is therefore blind to others. Men, people in midlife, older people and people with different bodily starting points often do not recognise themselves in these descriptions — and the health system recognises them later too.

The third: categories invite comparison. In practice I see people use the names as a ladder — “mine isn’t as bad as a real case”. That comparison is never innocent. It works as an excuse to delay and sometimes even as a quiet competition. So in my room I use the name when it helps choose an approach, and leave it alone when it becomes a measure of worth.

The fourth drawback is quieter. Names create the impression that a disorder is something a person has, rather than something a person does in order to cope. That difference is not academic. If it is a thing you have, it seems it must be removed. If it is a way you learned to survive, the question changes: what will take its place. The second question carries considerably further.

When a doctor is the first address

Whichever picture is closest, the same holds: if fainting, heart rhythm disturbances, marked weakness, loss of menstruation or rapid deterioration in general condition appear, the first step is the GP. The same applies to thoughts of self-harm.

Psychotherapy is an important part of treatment, but it is not a substitute for a medical assessment. I have written about when it makes sense to start with a doctor in a separate piece on when a doctor is the first step.

What to remember

Anorexia, bulimia and binge eating disorder differ most in the relationship a person has with their own disorder: the first is experienced for a long time as an ally, the second as an enemy, the third as a personal failing. But all three stand on the same axis — self-worth has become dependent on food, the body and mastering both.

The boundaries between them are permeable, and the largest group of people does not fully fit any box at all. So the name is not proof that you are ill enough, and it is not proof that you are not.

If the question “which one do I have” is holding you back from asking anywhere, set it aside for now. Ask instead how much room the rules around food take up in your day. That answer says more than a name.