Julian Baggini on the philosophy of dieting

You’re in denial, Jules.” The soundman was right. Strapping a microphone radio pack to my waist, he could see my stomach was too big for the trousers he was hooking them to. I had been determined not to go up (another) trouser size or a belt notch, but my resolve only involved compromises to my sartorial comfort, not my diet. My waistline had been expanding very gradually for several years, the millimetres becoming centimetres, then inches, and I wanted to stop the rot before it became a serious health issue. So I bowed to the seemingly inevitable and set out to lose weight.

Within six months I was more than 2 stone lighter. I now consider that a disaster, for reasons I’ll come to later.

Nevertheless, it wasn’t a complete waste of time. I did take some important lessons about willpower away from the exercise. In some ways I prefer the term self-control, because willpower can suggest that “will” is some kind of special faculty we call upon when really it is no such thing. On balance, however, willpower is the term that most clearly identifies what I mean in this context: the ability to do what you have resolved to do even when you feel inclined not to.

This ability is something the vast majority of dieters lack. Some lose their way by a thousand small violations; others go off the wagon in more extreme style. But why do we so often lack resolve? Often it appears to come down to impulse control: you may really, really want to lose weight, but faced with the temptation of a chocolate brownie, your desire only needs to overrule your resolution for a minute or two and your good intentions are vanquished.

Experiments with toddlers show that even at a very young age, some people are able to resist or defer gratification better than others. This matters for more than just weight loss: it turns out that having good self-control is a very strong predictor of academic and career success. Psychologists Angela Lee Duckworth and Martin Seligman have conducted experiments that suggest that the ability to delay gratification predicts academic performance much better than IQ. (Whether it is the cause of this success, however, is less clear.)

What makes the difference between those who have this control and those who don’t? The key, it seems, is how much we are able to think about our thinking: “metacognition”, as it is known. In a classic experiment, children who resist taking a marshmallow that others gobble up don’t desire it less; they are simply better able to distract themselves, or think of something else.

The importance of metacognition rings true in my own case. I really, really like food. If you think the reason I stayed on my diet wagon is that I just don’t get tempted, you don’t know me. I was able to resist partly because of a particular piece of metacognition known as an “all-things-considered judgment”. The reason why many people fail to stick to their resolutions is that they think they have a clear goal, but they haven’t actually thought about it enough, and are in reality much more ambivalent than they believe they are. So, for instance, they think they have decided definitely, clearly not to eat any sweet things, but they haven’t fully taken into account the fact that they also believe, of any given cake, that it really wouldn’t be so bad if they ate it after all, or that it is wrong to deny oneself too much, or that being good means giving yourself some reward. So when faced with temptation, one of these reasons becomes the basis for the judgment “Go ahead.”

This also points to the importance of what in the addiction field they call bright lines: limits that you just don’t cross, not even with a toe. The importance of bright lines is to eliminate discretion. The moment you give yourself options, the possibility of weakness of will forming a coalition with self-deception becomes too high. Take the rule “Don’t drink too much.” How much is too much? Not one more, surely? Not one more after that? You can see where that is going. The same applies for too much cake. A little bit? A little bit three days in a row?

When you have bright lines, it’s easier because you know exactly what you have to do and you don’t have to think about it. No alcohol today is pretty clear. If you are offered a drink, you know the only way to stick to your intention is to say no.

There are problems, of course. First of all, if you don’t sincerely believe the bright lines matter, when it comes to the crunch, you may be willing to cross them. So, for instance, if you really don’t think one drink makes any difference, then the bright line may not do its job in stopping you having one. So it’s not enough to draw a bright line; you have to believe in respecting it.

The other main problem comes if the line is in too restrictive a spot. Trying to lose weight is not a life-or-death matter, and if everywhere you see delicious food there’s a line saying “Do not cross,” life can become miserable and claustrophobic.

So how do you draw bright lines that work? First of all, it is important to remember that, in a strange sense, they are always drawn somewhat arbitrarily. Take the intention to quit smoking. It will always be true of any given cigarette that it doesn’t matter if you smoke it. It makes no difference if this fag is the last one, or the next one is, but, of course, if you had that thought every time you had to decide whether to smoke or not, you’d never give up. What you have to realise is that it is arbitrary which cigarette is your last, but one has to be. You then pick the arbitrary one and stick to it.

Losing weight is similar. It is always true that it doesn’t matter whether you have any given drink or slice of cake. It won’t make a difference to whether you ultimately lose weight or not whether you use oil in the particular dinner you’re making. Any individual choice is too small to matter, but in order to stop the small choices accumulating, you need to just say, “These are the rules and I’m going to stick to them.” Taken individually, each choice is arbitrary, but it is not arbitrary to say that you will allow yourself no discretion in any individual case, because that is the only way to make sure that the plan works.

It does, however, help to remember the arbitrary nature of each individual prohibition if you lapse. Then it really can help to say, “That doesn’t matter, just as long as I don’t do it again.” Unfortunately, people often get so convinced that they have to follow the rules that they feel one lapse has ruined it, so they may as well smoke the whole packet, drink the whole bottle or eat the whole cake.

As well as the idea of bright lines, the addiction field also bequeaths us another technique for exercising willpower: urge surfing.

As I discovered, although there are strategies for reducing the hunger caused by losing weight, there is no safe way to avoid it. In dieting, there’s no such thing as a free skipped lunch, but you can “surf” the urges hunger induces. The first time I did this was completely accidental. Travelling to a meeting, I was feeling so hungry I thought I’d have to have a banana, but I didn’t have one on me, and by the time I had the opportunity to buy one, my pangs had abated a little and it was getting closer to lunch, so I didn’t. Something similar happened a few days later and I learned the simple lesson that sometimes you can just ride out desires and they pass. A craving that is not satisfied will often give up and go away.

I’ve been urge-surfing ever since. It doesn’t mean never acting on hunger, but simply giving it a chance to ease of its own accord. And if it doesn’t? The back-up comes from mindfulness meditation. The idea, applied to diet, would be that you observe your hunger in a somewhat detached way. The thought “I am hungry” is not usually experienced as a mere report. It has the implied corollary that I should do something about it. The challenge is simply to allow the thought to be a thought. “I’m hungry.” Well spotted! And your point is?

Nothing. Just that I’m hungry. It’s OK to be hungry. People get used to much worse chronic pain. It sounds obvious: just as you don’t need to have sex or masturbate every time you feel a bit aroused, you don’t have to eat every time you feel hungry. Just accepting that – really accepting it, believing it – makes a lot of difference.

Perhaps one of the most important lessons psychology teaches about self-control is that conscious willing has a rather limited role to play, sometimes even a counterproductive one. This has been a recurring theme of work on appetite, which I got to discuss with three leading researchers in the area over a suitably modest lunch: Jeff Brunstrom, Peter Rogers and Charlotte Hardman from the University of Bristol.

“From a psychologist’s perspective, it’s a mistake to say that control has to be conscious,” Brunstrom told me. There is such a thing as effortful deliberative cognition, “where we battle and wrestle with our own appetite perhaps and then reach a point where we decide, almost against our will, to stop eating”. But he thinks it is “a mistake to assume that when we don’t do that, there’s a lack of cognitive control” or “to think that automatic behaviours are somehow bad and conscious controls are somehow good”. Consider, for example, driving. Obviously you are controlling the car – what else could be? But at any given moment you are often not conscious of what you are doing, and it would be odd to conclude that therefore your mind is not engaged in the task.

When it comes to appetite and eating, Brunstrom and others have found that “There isn’t a very strong relationship between capacity to engage in dietary restriction – to consciously restrict intake – and [low] BMI. If anything, it’s the opposite: people who are heavier tend to engage with that kind of behaviour.” Why that should be so is not entirely clear, but work by Brunstrom’s colleague Peter Rogers suggests that the constant engagement with the effortful mental activity of restriction could result in degraded cognitive performance.

In effect, you’re expending so much energy making one kind of mental effort that you don’t leave yourself enough for others. This suggests that although metacognition can be useful in impulse control for one-off temptations, relying on it as a medium- or long-term strategy may not work.

It also turns out that what we judge to be “enough” has little to do with how the food physically affects us. “With a typical meal you’re getting nowhere close to maximum fullness,” says Rogers, “so the change in bodily sensation is relatively small.” That’s why amnesiac patients who soon forget they have eaten a full meal will happily down another. “They don’t feel fullness,” says Brunstrom. “They just feel discomfort.” Similarly, people given bowls of soup that are, unbeknown to them, being constantly refilled from a hole in the bottom will end up eating much more than they ordinarily would, because in their heads it’s just one bowl.

What is going on in these and similar cases is that there is what Brunstrom calls “a fine-tuning of feedback from the gut”, which can be based on a memory of what you’ve eaten, beliefs about how filling it is or perceptions of how big it is. The good news is that if you do want to control what you eat, there are plenty of things you can do to affect all these and pull the unconscious levers of appetite. One of the simplest is planning. People tend to eat what is in front of them and, as long as it is not too meagre, be satisfied. Cook or order the right amount and you’re less likely to over-eat. What you need to counter is the natural evolved tendency to play safe, which in this case means erring on the side of too much rather than too little. This leads to what I call the tapas paradox: when ordering in tapas bars, people almost always ask themselves, Will that be enough? and order one more plate just in case. Yet this is just the rare kind of restaurant situation in which under-ordering is no problem at all, because you can always order more later. The little rule we should internalise here and at all times is that when you ask, Will that be enough? assume that it is, knowing that it is almost always possible to get a little something else after if it isn’t.

Willpower may not always be the best form of self-control, but it is nonetheless a capacity we should prize. Even if your only motivations are hedonistic, you often get more pleasure if you have the ability to exercise some measure of restraint. Most obviously, your medium- to long-term happiness is not served by pleasurable actions with serious negative consequences down the line. The clever hedonist takes into account future pains and pleasures, not only those right in front of him or her. Take the simple example of cake. Eat it every day and (for most people) it ceases to be such a wonderful pleasure, but that does not mean that if you eat it only once a month, you’ll get more than thirty times the satisfaction from that one slice. I think I’d get optimal hedonic value out of cake by eating it two or three times a week, which is sadly a couple of times too many for my lifestyle and metabolism.

Having said all this, we should be careful to distinguish delaying gratification from denying it. The desire not to act on desires can morph into the puritanical belief that all worldly pleasures are in some way distractions or traps. We do not want to become like Francis of Assisi, who, according to a contemporary biographer, believed, “It is impossible to satisfy need without yielding obedience to pleasure.” On the rare occasions on which he “allowed himself cooked food”, he “would often mix it with ashes, or quench its flavour with cold water”. For me, self-control is not a way of avoiding the evil temptation to enjoy yourself. Rather it is simply a means to enjoy oneself more deeply, and to keep in mind the fact that enjoyment is not all there is to life. I certainly learned a lot about how willpower works when I lost weight, and the combination of setting fairly clear bright lines, formulating all-things-considered judgements, being mindful of hunger and practising urge-surfing were sufficient to do the job, in the sense that I stuck to my plan and hit my target weight ahead of schedule. Unfortunately, it turned out to be a pyrrhic victory. I had successfully stuck to an ultimately unsuccessful plan.

Even as people were congratulating me on my new svelte shape, I was reminding them, and myself, that losing weight is, relatively speaking, the easy bit. The really hard thing is keeping it off.

At the time of writing, here I am, eighteen months later,and my weight (but oddly not my waist) is more or less back to where it was. That is not, however, the most humbling aspect of the entire experience.

I have discovered things about myself over the last few years that have not made me proud. Feeling hungry and low on energy day after day often badly affected my mood. I found myself being visibly irritated in queues, even though it was not the fault of the person serving me. My elbows came out in crowds, even though other people were as stuck in them as I was. Worst of all, I once stuck two fingers up at an officious woman directing me at a car-boot sale. I meant to do it behind the car door, out of sight, but I’m pretty sure she saw me. This is shaming and pathetic stuff. I also found myself being more forceful in discussions and less tolerant about slips in time schedules. What losing weight exposed is nothing other than a slightly exaggerated version of my normal self. I have witnessed in fames veritas, the truth in hunger, and it is not flattering.

There is one potential consoling thought here. As I’ve said, it is not as though I am totally out of control. I can catch myself, apologise and adjust to some extent. Perhaps this is what free will, for want of a better name, is really about. How we feel, think or act immediately is too automatic for us to be blamed for. Maybe you can’t help a stab of Schadenfreude, a snort of derision or a pang of envy, but you can help what you do with that feeling. You can choose to act on it or not, and you can also choose how you act in the future to minimise or reduce such feelings. The paradox is that in order to be more in control in this way, you often have to accept the many things you cannot control. Free will is not, then, about our ability to be right or wrong first time. It’s about our ability to correct ourselves.

Seeing my worst side, recognising how feebly I am able to resist small biochemical changes, coming face to face with the limits of my free will, I’ve had to eat so much humble pie it’s no wonder my waist has expanded again. What is most frustrating is how close I was to knowing all this when I started. It was there in the fundamental principle I based my regime on, if only I could have seen it.

The basic insight is that the reason most dieters piled the pounds back on after they had lost weight is that what people do while they are dieting is not sufficiently continuous with what they do afterwards. To work, losing weight has to be continuous with keeping it off. This is something Aristotle would have understood. Aristotle argued that knowing rules is not good enough, because we are creatures of habit and cannot always (or even mostly) stop and think about what the right thing to do is when confronted with every single choice. Dieting usually works against the grain of habit at both ends. When you go on a diet, you are asked to radically change what you eat from day to day. This makes sticking to the rigid new regime very hard. And once you’ve stopped it, the diet you go back to bears little relation to the one you’ve been on. This means you have learned next to nothing from losing weight about how to keep it off.

So I sit here now humbled by both my personal failings and the inherent difficulties all humans have in taking charge of the one thing of which they are supposedly sovereign: their own bodies. My only consolation is that humility, so long as it does not descend into pointless self-loathing, is a virtue. No one becomes a lesser human being by becoming more aware of their limitations. While it would be wrong to become apathetic in the face of them, it is only by fully knowing the limits of our powers that we can make the most of the ones we have, and perhaps even learn how to increase them.

This is an edited extract from ‘The Virtues of the Table: How to Eat and Think’ by Julian Baggini (Granta Books, £14.99)

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