I’M not sure when it was that I first realised I was suffering from bulimia. I’ve never confessed it before. Out of shame, I suppose, or embarrassment or because it’s such a strange thing for someone like me to confess to. People normally associate it with young women — anorexic girls, models trying to keep their weight down, or women in stressful situations, like Princess Diana.

Then, of course, with my weight, people wouldn’t suspect it. I never looked as if I was bulimic, unless you know some of the telltale signs. You could say I wasn’t a very successful bulimic, in that my weight didn’t really drop. But, of course, that wasn’t the main reason it started.

It was at its worst during the years when we first came to power and I was running a very big department, but it had really begun some years earlier.

In my case, it was partly associated with stress. I was working too hard, putting in enormously long days, 16 and 18 hours of solid work. I’ve always done that, of course, since I first entered politics, as if trying to prove that I was up to the job.

Once I got into the shadow cabinet, trying to produce pamphlets and documents, stuck in an office, hour after hour, the only break I ever took was to eat. That’s all I did. Work, and then quickly eat something. It became my main pleasure, having access to my comfort food. So what I did was stuff my face with anything around, any old rubbish: burgers, chocolate, crisps, fish and chips, loads of it, till I felt sick — but at least I’d had the pleasure of stuffing my face and feeling really full. Then there would be a weird kind of pleasure in vomiting and feeling relieved.

I suppose other people might have taken to the bottle, but I didn’t. Well, now and again, once or twice a year, when I was absolutely knackered, I did get out a bottle of vodka and place it on my desk. The office hated it when they saw that happening. They knew I'd go at it full pelt, as I always do with everything, and empty the bottle. But that was very rare. As I say, once or twice a year. I think getting out that vodka bottle was a cry for help, a cry for sympathy, to let people see how I exhausted I was.

It seemed to ease the stress, loosen the inhibitions, but I never liked doing it, or the after-effects. And, really, I didn’t enjoy it. I don’t like the taste of alcohol.

But food, I’ve always loved the taste of food. So, instead of the odd vodka, I’d just turn to some digestive biscuits, which meant a packet of them, scoffing the lot, then perhaps another packet.

I could sup a whole tin of Carnation condensed milk, just for the taste, stupid things like that. Marks & Spencer trifles, I still love them, one of my favourites. I can eat them for ever. Whenever I go to Mr Chu’s in Hull, my favourite Chinese restaurant in the whole world, great atmosphere, great people, I could eat my way through the entire menu. But I was ashamed of this gorging, this greed, and pretended I wasn’t doing it.

At home, I would say, “No thanks,” to Pauline when she offered seconds, but behind her back, I’d raid the kitchen or the fridge. Same at the office. I became a secret eater, hiding food and snacks, then trying to eat them when no one could see me.

When I was younger, at sea, my weight had been just over 11 stone, which was pretty normal for my height. I always say it’s five 10 but I think it’s nearer five 9. I blame an accident in a car on the Humber bridge in 1981 when I broke my back and lost an inch.

In photos when I was courting Pauline, I look quite slim, still around 11 or perhaps 12 stone. We used to do a lot of dancing, at jazz clubs and local hops. Oh, aye, we were great little boppers. I think 13 stone is probably what I should be, for my build. I’m large-boned, and I was always quite muscular, especially in my boxing days.

My weight gradually crept up over the years, with more sitting around, less exercise, more binge eating. The most I’ve been is 16½ stone. I certainly didn’t want to be any more than that.

I don’t know how I learnt about what bulimics do. I can’t remember reading about it or being told by anyone. I just worked it out for myself. As I was getting all this pleasure stuffing food in, perhaps if I could get it out, I could carry on eating, do the same the next day. So I started deliberately sicking it up. I’d go to the toilet after guzzling, put a finger down my throat, and make it all come up. It was surprisingly easy.

I thought, of course, I was being clever, and no one would ever know, but Pauline realised in the end. The signs in the toilet gave it away, and all the missing food.

Pauline knew about bulimia, having read about it in women’s magazines and followed Princess Diana’s story. Apparently, when her marriage was under stress, she became a bulimic. Pauline warned me of the consequences, which I hadn’t been aware of — how it can damage your kidneys. Also, the bile rises and affects your glands so you look all swollen-faced and swollen-necked.

It’s to do with the acids, causing inflammation, I think. I hadn’t been aware of the effects, but I can look back now at old photos and work out what was causing me to have such a swollen face at certain times.

They soon found out in my office, just as Pauline had. You think you’re keeping it a secret, but you’re not. Pauline persuaded me to seek medical help. I went to see the House of Commons doctor, who sent me to a consultant. My appointment was on February 19, 1991. I turned up and found his waiting room full of young women. I was the only man there. I felt a right twerp.

Luckily none of them shopped me to the press. Perhaps they thought I was on a fact-finding mission, never for one moment thinking that a man of my age and build could be suffering from bulimia nervosa, but that’s what the consultant said I had.

He asked me lots of questions, most of which I thought were daft — about my childhood, early sexual experiences, that sort of stuff, which I don’t think had anything to do with it. I was just under pressure and seeking relief in eating too much, then sicking it up — that was all there was to it, as far as I was aware. He explained all the side effects and advised certain diets, which I did try to stick to, but not always with much success.

Around the same time, I found I had diabetes, which was another reason why I was feeling so tired. The medication was a great help and I felt better after that was sorted. I was also driving Pauline mad by my snoring. I was found to suffer from sleep apnoea — a symptom of which is heavy snoring. That was connected with the overeating and bulimia.

I also had lots of tests for allergies. I discovered that when I was eating a lot of digestive biscuits I was more bad-tempered than normal. They gave me tests in case I had any flour allergies. It looked as if I might, but the tests proved nothing. But cutting down on digestives seemed to help.

I haven’t suffered from bulimia for more than a year now. I try to exercise in the gym for 45 minutes every day. My weight, though, is still over 15 stone — as I do love my food — but I try not to snack between meals and to eat at sensible times. I’m sure it was to do with stress. I wasn’t doing it all the time, and there would be gaps of weeks and months, but during those years when we first got into power, I let things get on top of me and took refuge in stuffing my face.

After I developed diabetes in 1990, I made it public, getting involved in a government initiative to make people more aware of the illness. Then in the 2001 election, I launched a mobile diabetic unit to tour rural areas to examine people’s eyes and identify the early stage of diabetes cases. I have continued to keep in contact with the unit and launched a diabetic awareness NHS campaign with Alan Milburn, the then health secretary. I heard that it led to capital investment in a nationwide NHS scheme to increase awareness of the illness.

Now I’ve come out about my bulimia, I hope I might do something to help the many young women — and others — who suffer from it.

© John Prescott 2008

Extracted from Prezza: My Story: Pulling No Punches by John Prescott to be published by Headline Publishing Group on May 29 at £18.99 and to be serialised in The Sunday Times next month

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