03/02/2013 11:25 GMT | Updated 05/04/2013 06:12 BST

Fat and Fabulous?... Well, No Actually

I simply have no patience for the 'fat and fabulous' warriors. That's fine for them, if that's what they're happy with. But it doesn't work for me, at all... I can't be kind to the lump in the mirror.

Hilary Mantel is a writer of rare ability. My first encounter with her work was when I read Wolf Hall, during the summer before last. I forget everything else around me, as I entered a world painted so vividly that I could almost smell it.

Indeed, it was often a disappointment when I had to re-acclimatise to the real world. How banal paying the milkman, making a sandwich, or travelling into Bromley to buy cotton wool pads, seemed after full immersion into the world of Thomas Cromwell. I loved every single moment of it.

I haven't actually read Bringing Up the Bodies yet - it's on my reading pile as we speak - but if its anything like Wolf Hall, Mantel deserves to lap up every single plaudit that has come her way.

But this isn't a book review. I am writing this article in response to Mantel's article about her weight in Saturday's Guardian. Due to various health problems, she is overweight, and admits that she fantasises about being thin again. I applaud her candour, and her bravery, and the ability to stand up - in the face of the 'Fat is a Feminist Issue' brigade - and say, 'there is an alternative to fat, and, yes, I dream about going there again'.

The matter has particular resonance with me. I have always been slim - a slim child, a slim teen, and a slim young woman. I rejoiced in my 23 inch waist, my small breasts, and the fact that I weighed a steady 52 kilos, for a very long time indeed. My mind-set was 'thin girl'. I bought 'thin-girl' clothes in sizes anywhere from 8 to 10 - never anything above. My weight wasn't an issue I ever thought about - as many naturally thin people will tell you, it's taken as given that is never even thought about.

But my 'thin-girl' vision of myself was shattered in 2009, when I was hospitalised in a psychiatric ward for nine weeks, following what was later diagnosed as a 'stress-induced acute nervous breakdown.' I was placed on anti-depressant medication to pre-empt any future dips in mood that would lead to a re-occurrence of my hospitalisation.

I didn't notice it while it was happening in the early stages, but weight began to creep on to my previously lithe frame, which I can only attribute to the side-effects of the medication. I've spent hours researching the side-effects online.

My diet didn't change, and although I am now self-employed as a freelance writer, as opposed to dashing round London as a legal secretary, my activity level hasn't really altered that much.

Over the course of the three years that I have been on the medication, I could hardly avoid the fact that I had firmly kissed 52 kilos goodbye. And the effect that has had on my body confidence is devastating.

After years of 'thin-girl' thinking - practically my whole life - having to go into a store, and buy clothes that are three to four sizes larger than you ever thought you'd need makes me want to cry like an infant.

My previously pert breasts are now enormous beyond what I ever could have imagined. I actually despise looking at them. Such disgust in my body seems harsh, and self-indulgent, maybe. But I live every day with the thought that, every time I look in the mirror, the body that I see is not mine. It's a form of body dysmorphia, I suppose, but with real evidence that the body I see actually does look as bad as I imagine it is.

In my own situation, I simply have no patience for the 'fat and fabulous' warriors. That's fine for them, if that's what they're happy with. But it doesn't work for me, at all... I can't be kind to the lump in the mirror. My husband rails against me in my despair - you're not as fat as you think you are, he says - but when I desperately want to be thin again, I can't accept anything less. It's not a social pressure - the pressure comes purely from inside me.

But within the last two weeks, at the very limit of my self-loathing, and fed-up with futile kicking and screaming, I've started to make positive changes.

I have ditched the anti-depressant medication. Before you get mad, and tell me that I am sacrificing my fragile mental health for the sake of vanity, my mental health is actually not that fragile at all.

My doctor has told me that I am not depressed. That I am not even a depressive, and as such, do not really need to be on the medication anymore. In fact, taking my weight related misery into account they would rather me not be on it. My breakdown is viewed, in retrospect, as being related to environmental pressures - overwork, mostly - rather than anything organic inside me.

So I've stopped taking the medication.

I've also done a week on the 5:2 or Fast Diet. This involves two days of 500 calories a day, in a week where you can eat like normal for the rest of the time. It's the latest thing - medically lauded for its practicality, and the positive effects it has on everything from your risk of developing diabetes, to your vulnerability to cancer.

And I think it's wonderful. The fast days are cleansing, and have a knock on effect on the way you eat on your normal days. I find that I don't want a second helping anymore even on 'normal' days, and I would rather have the crisp bread than the bag of crisps.

I may be jumping the gun, but I'm already starting to notice a difference. My waist looks smaller, and my little pot belly seems a fraction flatter.

I'll keep you posted on my progress.