The Diet That Never Ends: Where Control Turns into a Disorder

“I’m not on a diet. I’m just being a bit careful.”

I hear that sentence more often than almost any other. It is said in passing, between other subjects, and every time it stops me – not because it is worrying in itself, but because it is so very common. Being careful is our culture’s default setting. One person is careful from May until the holidays. Another is careful from January. And another has been careful for so many years that they no longer remember when they last stopped.

This piece is about that third group. About the diet that never ended, and about the question of where the line runs between control you have and control that has you.

Why the line is blurred and why it exists anyway

An eating disorder almost never begins as a disorder. It begins as something the people around you praise. Discipline, self-care, order. It is one of the few forms of mental distress that everybody applauds in the first month – and that is exactly what makes it so hard to catch early.

The line does exist, though; it simply does not run where we look for it. It does not run through what is on the plate. Two people can eat in exactly the same way, and for one of them it is simply what they like, while for the other it is a daily negotiation with their own worth. The plate says nothing about that. What does say something is the inner relationship: how much room this thing takes up, what happens when the plan fails, and whether you have choices or only rules.

So in my room I never ask what someone eats. I ask what happens if they eat something other than what they intended.

What restriction does to the mind

The most instructive evidence on this did not come from eating disorder research at all, but from a study of starvation carried out in Minnesota in the mid-1940s. The volunteers were men who were psychologically entirely healthy beforehand. After a period of serious deprivation they developed something anyone today would recognise as an eating disorder: preoccupation with food, ritualised behaviour around meals, irritability, social withdrawal, loss of interest in almost everything else.

That was not their personality. It was the consequence of deprivation. And this is the part that is hardest to accept: a great deal of what sounds like “bad mood” or “no discipline” or “not wanting it enough” is, under restriction, a physiological effect. A brain that is getting too little occupies itself with food more, not less. Preoccupation is not a sign of weakness. It is a sign that the body is doing its job.

Something uncomfortable for the marketing of eating regimes follows from this: prolonged restriction by itself produces precisely the behaviour it claims to remove.

Why control feels so good

Almost everyone who comes to me with this has anxiety somewhere behind it. Not necessarily recognised, often without a name. And food is, unfortunately, an extremely effective tool for calming anxiety in the short term – not because it solves anything, but because it is measurable. When everything else is unmanageable, this is one thing I can manage. A plan for tomorrow is something nobody can take from me.

In the nervous system this effect is real. Predictability soothes. That is why control works – and why it is so hard to put down something that genuinely lowers distress. Anyone who calls it foolish has not understood what it is for. I have written about what happens during anxiety in the piece on anxiety in the brain.

The problem is the price. Control soothes for ever shorter periods at an ever higher cost. The rules have to tighten in order to keep working, and one day there are so many of them that there is no room left for a life.

What long-term research on dieting in young people shows

One of the most cited longitudinal studies in this field is the American Project EAT, which followed adolescents over several years. The finding that surprised a good many people at the time: those who reported dieting in adolescence were later more often among those with a disturbed relationship to food – and in terms of body weight they were no better off than those who had not dieted. Dieting in adolescence turned out to be a predictor of trouble rather than a solution to it.

How you read that matters. It does not mean that everyone who has ever changed something about their eating develops a disorder – the large majority do not. It means that restriction is one of the most consistently confirmed risk factors we know of, and that in young people it is more often the entry point than anything else.

Three signs I take seriously

When someone describes their relationship to food in conversation, three things make me pay attention. The first is rigidity: do the rules ever adapt to circumstances, or do circumstances always give way to the rules? Flexibility is the single best indicator of health in this territory.

The second is social withdrawal. Once a person starts choosing where to go on the basis of whether they will have to eat in front of others, something has shifted. An eating disorder almost always narrows the world, and it does so gradually, with reasonable-sounding excuses.

The third is what a departure means. If departing from the plan is merely an unpleasant day, all is well. If departing is a moral event – evidence about what kind of person you are – then we are no longer talking about eating but about self-worth. At that point the conversation is elsewhere: with the inner critic, and with guilt that no longer does anything useful.

Why this is the disorder others find hardest to see

We notice anxiety because a person trembles. We notice depression because a person stops getting up. Continuous restriction is the only one that looks like a virtue.

In a society where being careful is the default, the disorder hides inside a perfectly ordinary conversation. Colleagues discuss their own rules over lunch. Friends compare what they are not eating this month. Someone who is deep in trouble sits in the middle of that and does not stand out by a shade – because everyone is speaking the same language. Their behaviour is not strange, merely a little more consistent than average. And consistency is rewarded in our culture.

Which is why this subject has one peculiarity in my practice: it is almost never brought by anyone else. With other kinds of distress, a mother, a partner or a friend often rings. Here the person rings themselves, and usually only once something else has worn them down to the point where they cannot go on. Most often, tiredness. Not fear of consequences, not other people’s concern – tiredness at facing the same task every day.

If you are close to someone this worries you about, the most useful question is the one that does not touch food at all: does this leave you with less room for other things? A comment about the plate opens a negotiation and a defence. A question about room opens a conversation. And if it turns out that you have to sit with an answer you will not like, it is worth reading the piece on setting boundaries too – concern also needs a boundary, or it turns into control over someone else’s control.

Where this article does not apply

Now against myself, because it would be dishonest otherwise. Not every attention to food is a disorder, and it would be harmful if anyone read this piece that way.

There are people who have a way of eating prescribed for medical reasons – with diabetes, coeliac disease, allergies, after certain procedures. Their rules are rigid because they have to be, and that is not a disorder. There are athletes whose profession demands precision. There are people with ethical or religious reasons who are entirely flexible in everything else and are not burdened by food. And there are many people who once changed something, found it did not suit them, and stopped – with no consequences at all.

The difference is not how many rules you have. The difference is what the rules do to your worth and how much of the world they take from you. Someone with serious medical restrictions can be completely free on the inside. Someone with not a single restriction can be on trial at every meal.

And one more thing: if you have a prescribed regime and notice your thoughts gripping it ever more tightly, that is not a sign that you are weak. It is a sign that it is worth telling the doctor who manages that regime. Both things can be happening at once.

What therapy actually works on

We spend surprisingly little time on food. Far more on the question of what it would be like if this were no longer available. What would be left. What a person would have to feel if they did not have this thing that has been reliable for years.

The work is often about a thought ceasing to be an order. Not about it disappearing – the thought “I shouldn’t” will probably keep arriving for a long time. But the difference between having a thought and being commanded by it is the whole difference. That is the core of cognitive defusion, which in these cases proves more useful than trying to convince someone that they are wrong.

The second part is flexibility, practised small. Not a great leap, but one place where a rule loosens slightly, and then watching what actually happened. Almost always less than fear predicted.

When this is no longer a conversation for a therapist

When the body is affected, a doctor comes before everything else. Fainting, heart rhythm disturbances, periods stopping, rapid deterioration – these are not subjects for a therapy room but for a surgery. Therapy does not work on an unstable body, because a brain in deprivation is not capable of what therapy asks of it.

With adolescents one further thing holds: the first choice is not individual therapy but treatment that includes the family, in which parents take over responsibility for eating for a time. That is not an accusation against parents. It is simply the approach with the strongest research support at that age.

If you are wondering where to address the first question at all, I have written about how to choose a therapist.

What to remember

The line between control and disorder does not run through what is on the plate but through how much room the thing takes up, how flexible the rules are, and what it means when the plan fails. If departing from the plan is a moral event, we are no longer talking about eating.

Restriction by itself produces preoccupation with food – that is physiology, not character, and we have known it since the 1940s. Dieting in youth is one of the best-confirmed risk factors for a disturbed relationship to food later on.

At the same time, not every attention is a disorder: prescribed regimes, professional demands and passing changes exist and are entirely legitimate. The key question is not how many rules you have, but how much of the world they take from you.

And if something snagged while you were reading – most likely at that question about what happens when you eat something other than you intended – that is not proof that something is badly wrong. It is a reason to talk about it while it is still small.