A fascination with being thin is a defining part of this rapidly fattening age and nothing exemplifies it better than the recent tumult in fashion and the media over the size zero physique. A size zero is officially 31½-23-34 — little-boy statistics that can be applied to some of the biggest red carpet names of the day. But the term doesn’t bring to mind vital statistics; it has come to represent a state of slenderness and richness that to most normal eyes looks like skin, bone, expensive hair and lovely clothes.

Personally I don’t care too much about the debate in fashion. Models have always been thin and while some have issues, generally the model’s body is an extraordinary one: they are a gangly slender breed unto themselves. More fascinating — and alarming — are the lengths other women will go to physically and mentally to keep themselves well under their natural body weight; and the extent to which most of them think their natural weight is essentially fat.

I am never quite satisfied with my body, but aside from largely healthy eating and regular exercise I can’t be bothered to do much more about it. However, when I was challenged to make a documentary about what it takes to attain the distinctive anticurves of the size zero, I said yes.

These are the lowlights of my descent into starvation.

Zero intolerance

Columnist and mum-of-three Jane Moore is worried about the effect that glamorising stick-thin models has on teen girls

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Week one

Am nicely fit, but a wee bit porky (just over 10 stone) after two weeks enjoying death by cheese and ham skiing in France over Christmas. I face the new year with the understanding that the next few weeks are going to be miserable. I will follow a lifestyle that, for example, an actress or singer might adopt were they getting ready for a red carpet event or a video shoot.

First up, the tried and tested master cleanse diet, a concoction of lemons, cayenne pepper, maple syrup and spring water, used most famously recently by Beyoncé to lose 20lb in 14 days.

Buy all the stuff and go home to make up fiery, sweet, sour filth that will be my sole nourishment. Within two days I know I cannot live on this stuff while working. Am agitated, bored — so bored — and have a feeble attention span. My legs might still look sturdy, but they struggle to climb stairs and my head is light as a feather. At times I woozily weave rather than walk.

Leaving the steam room one evening after an ultra-short session at the gym (must keep my metabolism up so that I continue to burn calories at a normal rate and not at a slow starvation rate), I pass out and fall against the wall. A woman props me up. “Sorry, I’m not eating much,” I say in a dizzy haze. She looks daggers: “Well stay out of the gym then, you are a danger to more than yourself.”

I get home and try hard to focus on my ambition to have an x-ray-like body. I try to enjoy the sensation of hunger, something I have heard women in the public eye say and have also read on anorexia forums on the internet. Enjoying hunger is not nourishing for me, and I eat 10 raisins, 10 nuts and a tablespoon of maple syrup feeling weak-willed and guilty. I am going generally nuts.

Appropriately I start eating about 500 calories of nuts a day because my job is impossible to do on the lemonade alone. My attention span improves — a bit. The master cleanse book recommends doing the diet for a minimum of 10 days and a maximum of 40, a state of affairs I find unimaginable.

Already I enjoy the feeling of emptiness in my body and every morning I encourage more emptiness by drinking two pints of salty water to cleanse my bowel. The effect is explosive. Obviously this isn’t healthy. I am also smoking a lot more.

So apart from making friends with all the people in the smoking room at work my social life has taken a nose-dive. I turn up to dinners after everyone has eaten; drink water, smoke, and go home exhausted by midnight. Call this life? However, a surprising number of women, when I tell them why I am not eating, say they have done the diet too and a strange sort of kinship over suffering is shared. Crazily it seems I am not alone.

Week two

Haven’t seen my mum or granny for months. Mum asks me when I am coming down. I tell her I won’t be coming home until this is over. Life in Devon revolves around physical exertions and big noisy wine-fuelled meals finished off with sticky nursery puddings. On this diet my happiest place is tucked up in bed alone, stomach grinding with hunger, wrapped round a hot water bottle (I am always cold) with some prescription-strength sleeping pills.

I have to fly to Miami to interview a Hollywood skinny. I cannot take fluids on the plane, so no lemonade. I survive the 12-hour flight on a small bag of nuts and some orange juice.

On arrival I go direct to the hotel to do the interview. I am now beside myself with hunger — I feel like I am floating — and am chain-smoking to try and get my wits together. While I wait for the actress at the hotel I eat some ham and raw vegetables. I try to talk to the Hollywood skinny about weight issues; she goes off the wall. Touchy!

After the interview I go for dinner and am so debilitated that I eat a small tuna tartare and have two glasses of wine. Then I crack — that’s the wine — and order some coconut cake. After a few mouthfuls I become hyper, like a kid after too many sweeties, rambling excitedly about how sugar acts on the same neural pathways as cocaine. Everyone stares — I am on a sugar high. My cheeks are flushed and my speech is speedy. I feel happy.

The next day I get up and run for an hour and feel really fat. The truth is, the more weight I lose, the fatter I feel and the more I want to lose weight. I lie in bed in the mornings feeling my hipbones and wanting to feel them more. I want them to jut out.

When an old friend asks me how I am getting on I grumble about how stupid it all is and say how sorry I feel for women who live out their lives in this state of privation. She’s cynical. “I think you’re enjoying this,” she says, knowing me better than myself at times. I secretly agree with her.

Week three

My boobs and arse are flat as pancakes, though the former specifically look awful. During the diet a male friend grabbed my bum and said “Yuck” because it was so lifelessly flat. When I get back to the UK I have to go for my weekly weigh-in and check-up with Dr Le Roux, the metabolic physician at Imperial College London who is managing my health. The weekend in Miami has screwed up my extreme diet.

The thought that I may have put on weight is stressing me out. Obsessive dieters need routine, or a personal chef with them at all times. I feel bloated and guilty. My mind is warped and I have arrived at planet thin where all that really matters — forget art, literature, intelligence, love, family, career — is getting thinner. I am food phobic and can’t stop thinking about sex. A girl needs some kind of sensory pleasure in life, and sex and smoking are the only ones left.

What a strange life, thinking about food all the time but eating none. And when I do, such guilt. I buy some laxatives, which is stupid given that I go straight from Heathrow to a detox retreat in Kettering where I will have daily colonics and consume nothing apart from fruit juice. But then I am becoming very stupid.

The laxatives give me cramps and I arrive at the Homefield Grange retreat tired, agitated and in pain. For the next five days I will have regular enemas. I also — against the wishes of the supervisor there — force myself to train twice a day, a normal activity for the weight-loss obsessive. I ignore almost all phone calls, even from close family and friends. I cannot concentrate on books so, in between the training and the colonics, I watch garbage television and read trashy magazines by day and long into the night because the hunger keeps me awake.

But when Dr Le Roux weighs me and I’ve lost more than a stone in three weeks, all that weirdness and suffering turns to elation. I love my increasing slimness. You can wear anything you want, you look great in photos; put on heels and your legs look like something out of a fashion magazine. I feel a peculiar sense of power and control, and an air of aloof removal from other women.

Against my sisterly instincts I have started judging other women’s bodies against my own, ruthlessly, from their ankles to their chins, which is clearly menacing. But as my entire life has been seized by this body-driven self-validation it doesn’t bother my conscience as it should.

Nothing much great is happening anywhere else in my life: my work output is intermittent as I can’t concentrate, socially everything is a drag, family life is a nono. My biggest excitements are the steam room at the gym, smoking and of course shopping — fashion is made for women of my physical proportions.

No fear that I frequently feel on the verge of tears. Not to worry that meeting men is harder without a drink in your hand, because if I keep this up I’ll be a trophy-wife weight, I’ll be the sort of thin that a certain type of man likes to buy into as he would a flash car. And with the obsessive shopping and debilitated mental capacities for intellectual combat, I’ll fit the brief perfectly.

I am suckered into the miserably compromised life of the artificially skinny. Yes, it’s a pain in my nonexistent arse not eating much. It requires a lot of concentration and you need to disconnect from certain bonding activities, specifically conversation, drinking and eating.

Week four

Stupidly, on my weekly visit to Dr Le Roux, I tell him about the laxatives and he immediately sends me to a psychiatrist. After a cold hour of being grilled, the psychiatrist says I have the potential to develop bulimia and I am told to start eating normally.

I am beside myself with anger. I have left work now and for the final month had planned to dedicate myself to getting down to a revoltingly thin state. Partly to see the experiment through; partly because this was something I really wanted to do. I wanted to know what it felt like to be as thin as a properly thin person. It’s true that the anorexic state is a cry for help — am I participating in this specific psychopathology? Too right.

With not much work to do I could really concentrate. I had found a personal trainer to help me find that rail-like state. I would train hard twice a day while eating only 1,500 calories, I’d sleep in clingfilm, sweating like mad. He planned to train me as you would a boxer or a jockey getting ready for competition. And in between all I’d do is sleep. But instead I am told to “eat normally”.

Week five

Eating normally? Forget it. My mind is not my own any more and what follows is up there with the worst weeks of my life. I have to go to the Alps for work. The story isn’t going well and I’m stressed. Under stress, when I need to write, I often eat. It’s not cool,I don’t like it, but I do. I am terrified and confused. My body is hungry, but I am continuing to try and control my eating. The consequence of this is bingeing. I binge and then stick my fingers down my throat — twice. Is ita shrink-fulfilling prophecy? All I want is to be thin. I am unhappy.

I go back to Homefield Grange with two friends for the weekend, raving about its weight-loss benefits. I tell them matter of factly about the bingeing and purging, thinking that this is normal. When they both express shock, I feel a sense of isolation and shame. Their shock makes me realise quite how silly things have become.

And it is totally within my power to sort my head out, but I don’t want to. Dealing with it will mean putting on weight. We flick through Heat, The People, Hello!. There is no diversion from slim women, including Nicole Richie, being presented as successful who are clearly living their lives in the ravages of eating disorders. I spend the rest of the weekend reading books about eating disorders. My intellect is starting to fight back against my misguided, hunger-fuelled, bizarre idea of vanity.

Week six

I want my eating to return to normal. Bingeing is distressing to mind, body and soul. And as soon as my eating becomes more normal my human relationships become simpler, and I steadily feel happier and calmer. Nonethe-less I feel a failure and I still think my legs look chubby. I weigh about 9 stone. Most of the thin girls in gossip rags are probably 8 stone or less.

Even though my head was a mess my female friends all thought I looked great when I was at my thinnest. The cult of thin is a powerful one and, truth be told, if I didn’t have to workI could imagine almost enjoying getting into it. In certain pockets of society everyone thinks natural body weight is fat. If you are a perfectionist, as I and many other marginally successful women are, you fit the psychopathology brief for eating disorders. At the weekly weigh-ins with Dr Le Roux, I made him put a piece of card on the scales so that I didn’t obsess about numbers. What I went through is all too familiar to him.

The pursuit of thinness is a way of channelling every emotional energy into one ambition; it is a way of losing yourself in one problem — weight loss — and ignoring all the other issues in your life. Almost all women want to be thinner. When a woman feels low, or challenged by life, sometimes any excess flesh feels literally like the embodiment of their perceived weakness. Control around food is seen asa sign of intelligence and restraint. It’sa seductive and all-consuming addiction when the figures on the scales are a simple, if nutty, method of measuring your success as a human being.

Super-Skinny Me: The Race to Size Zero, is on Channel 4, April 22

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