When the results of the survey are published this summer, they will prove what we have only hitherto guessed at. Decades of better nutrition and better medicine - as well as our sedentary TV-dinner lives - have made us taller, heavier and broader in the beam. As Philip Treleaven, professor of computing science at University College London (UCL) and head of the National Sizing Survey says, women are becoming tubular, men broader and heavier.

When the analysts have finished, they will be able to tell which region of Britain has the slimmest, fattest, shortest and tallest men and women. When it comes to women, who buy 70% of all clothes in this country, we will be able to know what proportion of them is pear-shaped, and what is apple-shaped. What's more, we will know where the pears and the apples live and, who knows, we might find a whole fruit salad out there.

So new is the study, the first of its kind, and now being copied by other countries, that the fashion industry is only just beginning to think about the implications of the data. The theory is that every piece of fruit should get clothes that fit them better, leading to happier customers, bigger profits, and the end to hideous Saturdays traipsing round the shops.

It won't just be the rag trade that benefits from this new science of bodymetrics. Professor Treleaven will present his findings this summer to a queue of epidemiologists, Whitehall mandarins and doctors who have long sought such data. "There are medical benefits from this technology," he says. "Body-mapping can ascertain muscle/fat ratio, help in reconstructive surgery for cancer sufferers, diagnose obesity, and may help anorexics, many of whom have a distorted body image."

But for the moment, and armed with millions of retailers' pounds, it's all about the high street and that niggling one-size-fits-nobody problem. The lack of sizing convention has long frustrated manufacturers and customers alike. Now the BSI, with its European counterparts, is aiming to use the data to arrive at a new set of sizes, adhering to specific measurements. It also aims to harmonise them across the continent. So, after the Euro-banana and Euro-sausage could come the Euro-torso.