1 We want to be thin but we lie about it

Since I’ve been a journalist, I’ve done a ton of diets for one article or another. I never had to justify it, or explain what I think about my own body, and how that relates to other women’s body images, and how the tension between living as a feminist and living as a woman in the world is resolved – because it was always for a piece.

But I went on diets before I was a journalist, and I never admitted it, either. It was always something else: I’m eating carbs eight hours apart from proteins because it’s good for my skin. I’m raw-fooding for spiritual reasons. These fermented foods are for my sluggish mood. To admit that you want to lose weight for its own sake (and this was even worse in the 80s, by the way) was unfeminist, unserious: you can’t imagine Rosa Luxemburg worrying about her batwings.

Then as now, it was impossible to overstate how much sheer approbation you got from being thin, from everyone: friends, colleagues, children, peers, people who hate you, people you’ve just met, in-laws, bus drivers – the thinner you are, the more people mention it. When you are not thin, there is simply an absence of praise, a discreet silence. Vogue once ran an editorial (ironic, coming from them, but whatevs) saying “women don’t stay thin to please men; they stay thin to dominate other, fatter women”. When I read it – at an impressionable age – it seemed so catty and stark that I thought it had to be true, except it’s not. Women who stay thin do it because they are also human, and as such social; existing among other people is much more enjoyable when they audibly approve of you the entire time. You cannot politics your way out of that.

So a double imperative lurks beneath every fad, every fake intolerance, every detox: be ashamed of your size, but also be ashamed of your shame, then cover the whole thing in silence. I think if we rejected the silence, that would be the first step towards saying, “Actually, all this shame is incredibly unfair.”

2 Respect the power of your own body

At school, everyone had an eating disorder. Once, someone had a genuine meltdown because she’d bitten the skin around her fingers and accidentally swallowed it, and didn’t know how many calories that was. We didn’t have Google then.

It was almost a requirement to be counting calories the entire time, and I could never figure out why I sucked at it so badly. One day I would eat nothing but a tin of tomatoes and some sugar-free jelly. The next, I’d stop at every sweet shop between my school and my house (six miles of heavily built-up streets). Why I was so pathetic? Why couldn’t I simply govern myself? This is a common theme in the obesity narrative: why can’t those people just try harder?

I didn’t find out until years later – when interviewing Robert Lustig, author of Fat Chance – what appetite actually is. It is a primal force. If your body thinks you’re starving (information it will get from hormones, not counting calories) it will override any other imperative until you’re not. And that hormonal mechanism, the one that tells the body, “I’m starving and I need to conserve energy” (or, “I’m not starving and I have energy to burn”) is strongly influenced by fructose. Not only can you not diet in the first – orexigenic – state, it is cruel even to ask you to try. It would be like asking your body not to pick up your baby when it’s in danger.

Willpower is a redundant concept in nutrition. It is basically a pipeline issue: you can get ahead of your appetite by working on your blood glucose (not eating refined sugar; eating foods with a low glycemic index, which release sugar more slowly) or your state of mind; but once the clarion call is sounded, your body wants what it wants.

3 Sometimes you think you want to diet. You’re wrong

In 2013, I went to a conference on obesity, and learned something revelatory. Professor David Haslam, now chair of the National Obesity Forum, said that five minutes of vigorous masturbation used 300 calories. Everyone in the room was agape, yet none of us had the nous to ask, is that for a man or a woman? Sorry, that wasn’t the revelation; I was just passing it on for your information; you could do that twice a day instead of spin.

The actual revelation was the sheer weight of opinion from psychologists and behaviourists about what obesity was: it was not ignorance; still less was it greed. It was a compulsive behaviour. One researcher, Jane Dalgliesh, described this quite plainly: “We used the Stirling Eating Disorder Scales, and when we used the scales to assess an obese client, we could have been looking at patients with anorexia or bulimia. The psychopathology was very similar.” Another said she’d never met a morbidly obese patient who didn’t have severe trauma in their past. Alice Mackintosh, nutritionist and co-author of The Happy Kitchen, tends to see patients for anything but weight loss, but observes that the few who do want that “leave feeling really good – and then they just can’t do it. They don’t need a nutritionist. They need a coach, a therapist. They need to sleep.”

Often, you think you need to diet when actually you need to self-soothe, which is just therapy speak for stop hating yourself. The more you try and fail to diet, the more you hate yourself.

4 Inclusions are more important than exclusions

I went to a nutritionist for the first time in 1999 (for a piece!). She was disturbingly perfect, neat and serene. With no visible pores nor the slightest blemish, she looked like an airbrushed photograph of herself. Her prescription was: no wheat, no meat, no sugar, no salt, no dairy. It was the age of exclusions.

Sure, it makes you quite thin, because your casual eating, your pork scratchings, your Pret sandwich, your someone-else’s-chips is disrupted. But there are bigger problems with exclusions than the futility of self-denial: probably the most important development on nutrition this decade has been Tim Spector’s book The Diet Myth, which describes the importance of variety in the gut biome. His abiding conclusion is the idiosyncrasy of every gut; there probably isn’t a single diet that would work on even the majority of people; and, with the exception of very highly refined foods, which do nothing for variety, it’s much more important to get weird stuff into your diet than it is to remove anything from it.

You’re aiming not for nutritional purity, but for a diverse microbial gut-garden. So, that’s any cheese not made in a highly clinical environment, yoghurt, Portuguese fermented sausages, seaweed, unusual mushrooms, kimchee, kombucha, anything you can imagine would have grown hair if you’d left it any longer.

5 Fat doesn’t make you fat

In 1996, I was 23, and working at the London Evening Standard. The Atkins diet was relatively well-established in the US (Atkins Nutritionals had been founded in 1989) but had only recently arrived here, and Jesus, had it. It was not at all unusual to go looking for a piece of paper on someone’s desk and turn up a shrink-wrapped steak that had been there for a month and was green.

Now officially classified as a “fad” diet, Atkins’s eating plan claimed strong foundations in science: cutting out all carbohydrates took you into ketosis, a state in which you metabolise fat at a faster rate, in contrast to glycolysis, where your energy comes from blood glucose. The diet was discredited (mainly when Atkins himself died and everyone said it was a heart attack, a consequence of his own mad diet; this was a myth, probably started mischievously – it was actually a head injury). But the diet flagged something important, by not making sense. With a packet of cashews, you could disappear 600 calories in five minutes, and still lose weight. All I ate was cheese. I wasn’t thin, but I wasn’t getting fatter, which is incredible, given how much I drank.

Fat makes you full, and sugar makes you fat: the worst thing you can do to yourself is follow a low-fat diet, since, especially in prepared foods, the manufacturers boost the sugar to make up for the fat, leaving you fat and still hungry. Cardiologist Aseem Malhotra explains: “The emphasis on low fat has been the direct cause of obesity and type 2 diabetes. We should focus on sugar and refined carbs. Most cholesterol is produced in the liver. When people consume too much sugar and too many refined carbs, it causes the liver to produce more fats and a process called insulin resistance.”

Atkins does work: the question is, how long for? Because it is tremendously hard to stick to. Less difficult would be to take the no-sugar element, keep the fat free-for-all, and add more roughage, as in Malhotra’s Pioppi Diet.

6 Fasting is good for you

In 2007, I got pregnant. My appetite was incredible, compulsive, towering. It could have been a truly enjoyable phase, a sensory adventure. The deliciousness of everything was so intense, it was like tasting in technicolour. But I didn’t enjoy it because I was repelled by my ungovernable self; every single day I’d wake up with some new intention – only protein, only wholefoods, for the love of God, at least no sugar. And every day by 11am, I’d be walking past a Greggs, gaping at the Tottenham cake, thinking, “What must it taste like, though? That beautiful pink icing. That sandy sponge, lighter than air. How would it be, in my mouth? What mad pleasure could that unleash?” I’d walk in bewitched, leading with my feet, like a cartoon. To this day, walking past a Greggs puts me in a good mood.

I put on 4st in the first trimester, and landed on the other side probably 5st overweight. To which the answer was: absolutely no fucking way. I’ve already fallen off the face of the earth, and the only appointments I go to are ones where people call me “mum” and not my name. I am not ready for the world of elastication and invisibility. I don’t care if it’s the fault of the patriarchy.

Then I discovered the Cambridge diet, which having been around since the 80s, is an archaic, intimate business, somewhere between seeing an Avon lady and buying contraband Cohibas in Havana. You had to find a practitioner on the internet and go to her house (it is always a her), and she would weigh you and sell you a bunch of milkshakes and powdered soups in small quantities, and you’d have to go back regularly so she could check you were normal, and, I tell you, it works. After all I’ve said about appetite being uncontrollable, there is good evidence that people find it much easier to fast, either with fake food (meal replacements) or in short bursts (the 5:2 diet, also madly effective), than they do to simply eat less.

Mackintosh, the nutritionist, spells out the physiological benefits of the fast: “Migratory motor complexes [waves of electrical activity that sweep through the intestines] can’t work unless you’re in a fasting state. It also has been shown to reduce inflammation, and that is linked to insulin resistance. The body can do more of this housekeeping when you’re in a fasting state.”

I was on the Cambridge diet, on and off, for six months, and I lost all 5st and then some. Intermittent fasting used to be both looked down on and considered dangerous by the medical establishment, something decent people didn’t need to do, and that weak-minded people might allow to get out of hand. That has evolved, but Rebecca McMananmon, consultant dietician and spokesperson for the British Dietetic Association, advises it is still not recommended for teens, pregnant women or anyone with a history of an eating disorder. However, if there are no pre-existing medical conditions, there are no overt risks.

It is somehow fitting that, when a diet finally arrived that worked for my weight-loss, it was also good for things unrelated: general health, immunity, mood. Almost as if those lies we’d been telling since the 80s (“Slimming? Me? No, I’m doing this to clear my skin”) finally became true. Since my fasting experiment, I have never thought about food and weight again, although I actively seek pickles for pleasure and would never let any seaweed go past me. A lot of the enduring obsession with diets is down to the sense that your body is this giant, incalculable mystery, constantly trying to trick you, as you trick it back. Stripped of its mystique, mine seems to stay more or less the same.

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