Help! It is hard enough trying to pass myself off as a size 12. Now there's extra pressure with the arrival in Britain of a size four - which translates as size zero in the USA.

With these tiny garments on the rails, a 12 is going to seem massive, and as I've only just managed to squeeze - and I mean squeeze, I can get into them but can't zip them up - into size 12 jeans after a decade in 14 or 16, it is unfair to raise the stakes yet again.

For years, during which I gave birth to my two daughters, I have let myself go, piling on the pounds without a care in the world. So what if a size 16 was a bit tight around the upper arms? Bingo wings are in vogue in these parts, aren't they? I didn't really care how I looked.

Then, with my childbearing years behind me, I cut out crisps and chips and threw myself into the punishing regime of walking to the car and back at least twice a day, and could soon wrestle myself into a 14.

A couple of years later and I can just about struggle into a 12.

But now a 10 will be seen as large, and a six medium. The ultimate aim will be a four, a size Asda's fashion label George will shortly stock.

I'm going to have my work cut out. I may have to replace doughnuts, burgers and hog roast sandwiches with pampas grass and water cress, but it will be worth it.

Seriously, there is a genuine concern among many, including Culture Secretary Tessa Jowell, that the promotion of such tiny sizes is linked to eating disorders, and that youngsters will feel pressured to fit into these clothes.

I know with 100 per cent certainty that I will never, ever - short of not eating for several years and running a daily half marathon - achieve the 22-inch waist that is a size four.

But I'm not going to let it get to me, and neither should anyone else. If shops want to sell Barbie clothes for real people, let them. And if they don't fit any part of your body other than your index finger, don't fret. After years of being overweight for my height, I have devised a series of measures to overcome the problem without having to drop a dress size.

These are my tips on how to look slim without losing weight: l Always stand beside someone larger than you.

l Wear clothing in colours that blend with the environment. If you're going to the park, wear green, for the school playground wear grey. With any luck, people will only see your face.

l Join the priesthood. As Dawn French aptly demonstrates in the Vicar of Dibley, a cassock is the ideal garment for hiding the flab.

l Enrol in an exercise class. Not just any class, but a sumo wrestling class. You probably won't be accepted at less than 20st.