The average teenage girl should eat about 2,000 calories a day; Georgia Davis eats more like 13,000 – which is why, aged 15, she weighs a colossal 33 stone.

In Friday’s edition of The Sun the poor girl posed with her daily intake of food: two loaves of white bread, two litres of Coca-Cola, eight pints of whole milk, 21 chocolate digestives, six packets of crisps, a mighty plate of chips, a chocolate cake and a lasagne.

This is the worst kind of food: processed, crammed with trans fats, grease, sugar and calories with little nutritional value. It’s the kind of stuff that most of us know is bad for us.

My first reaction was to ask: are there no vegetables or fruits in Aberdare, Rhondda, where she lives? Does her mother not know that letting a teenager pig-out every day on this lot is like handing her a loaded gun? Doctors say that Georgia, who has a body mass index of 74 – above 30 is technically obese – could drop dead at any moment. “I can’t walk more than a few steps without getting out of breath,” she says. Unsurprisingly she has type 2 diabetes and is bullied at school.

I feel incredibly sorry for Georgia. She has eaten herself into a blubbery prison – her vital statistics are a sobering 64D-62-74. She says she started to overeat when she was five, when her beloved dad died of emphysema and she turned to food for solace. It seems this was a family affair. Her mum, who has hit 31 stone herself but is now down to 20 stone, admits: “When her dad died we would comfort eat together.” I’m sure they were miserable, but allowing a child to scoff on this scale is tantamount to abuse.

We all know we have an obesity problem in this country. A quarter of British boys and a third of girls are overweight and teenage girls form the majority of the 1m obese under16s. The evidence is everywhere: I was at my local lido the other day and was shocked by the number of large bottoms and extra bulges – and that was only the children.

All around me there was serious snacking going down: humungous bags of crisps and ice lollies – and the latter have morphed from being smallish, water-based treats to mighty chocolate-covered and ice-cream-filled monsters.

I find the summer holidays are a constant battle against the consumption of too many convenient and easily available fattening treats. Often I feel mean saying my girls can’t have an ice-cream or sweets when everyone around is stuffing themselves – but I say no for their own good. I don’t want them to be fat. Taking healthy snacks such as chopped-up melon or a packet of blueberries instead of letting them eat crisps is more of a hassle, and more expensive, but I do it because I love them. I am their mum and it is my responsibility for them to learn to eat healthily and not to eat rubbish. And more than that, I know the misery of being a chubber.

I was never as fat as Georgia, but I’ve been pretty hefty in my time – as a teenager I remember vividly standing on the scales and being more than 14 stone. I understand how food can become a panacea for sadness and how making yourself into a considerable physical presence can provide a feeling of solidity when your emotional foundations are pretty shaky.

My father didn’t die, he left. And like Georgia, I was five, too. Luckily my mother didn’t assuage her own sadness by comfort eating with me. I managed to do that all on my own. Meal times were always pretty chaotic (five children, a nanny and shifting casts of others). I ate a lot of seconds and thirds . . . we’re a greedy bunch – we used to joke that it was the “quick and the hungry”.

For me, being fat was a cry for help – a physical manifestation that I was unhappy, that however cheerful or successful I seemed, everything was not okay.

My family didn’t like me being fat, it destroyed the myth that everyone had moved on after the divorce and we were all fine and happy. I think that in middle-class families there is more of a stigma about weight – in the UK, as in America now, obesity is often a poverty-related problem. (Expensive children’s clothes brands have much smaller sizes.)

In an attempt to make me more presentable I was taken to innumerable diet doctors, who prescribed dreary programmes (they always said “avoid” and then would list everything I liked most from brie to chocolate). I was even given several sets of amphetamine (speed) pills to control my appetite, which would mean I would do a whole day of school without eating anything and then come home and stuff down peanut butter and jam sandwiches.

I remember a particularly grim volume that haunted the kitchen called Cooking to Make Kids Slim (with a picture of a fatty on the front standing on a set of scales) and always having to have a “diet” packed lunch at school with a salad while everyone else ate chips. I don’t think that was quite the kind of attention I was seeking.

My fat was my cocoon, I dissolved my misery in it. Despite the concerted efforts of my parents, it proved impossible to shift until I dealt with the sadness that was located there. I was lucky in that I was a very strong swimmer and was always fit. And as I became more independent of my family and was able to carve out my own life, I shed my childhood baggage. The heartbreaking aspect of poor Georgia’s predicament is that the bulky manifestation of her childhood tragedy is now weighing her down so completely that she may die before she can escape it.

There is some hope, however. Georgia is off to a special school in the United States that specialises in treating cases such as hers through tough fitness programmes and diets – it aims to have her down to 20 stone, which the doctors say would save her life. I’m sure that in these American fat camps they also understand and work on the emotional components of obesity; I hope they can persuade her to stop using food to satiate her sadness and shed some of her bulk so that she can have a future.

The saddest part of Georgia’s interview was where she admitted that she spends most of her time on the internet in cyber worlds where she exists as a slim, attractive young woman as an alter-ego avatar.

“Online you can be who you want to be,” she explained. “No one judges you on what you look like. On the internet I’m married and living in a little house with two children. I would love that to be the real me one day.”

I’d love that for you too, Georgia. Believe me, you can leave your fat and its associated sadnesses behind. It really is possible. But to do that you have to stop eating 13,000 calories a day. Good luck!

Rachel Johnson is away

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