Jemima Lewis: What's the point of picking on fat people?

Would a man who never gets round to doing the chores be considered unfit for work?

Susan Chambers, Wal-Mart's executive vice-president in charge of benefits, wants to introduce an element of physical exertion into every employee's working day - "eg all cashiers to do some cart-gathering". Not a bad idea in itself, you might think: after a couple of hours on the checkout, lulled into catatonia by the bleeping of bar codes, it might be nice to stretch one's legs on trolley duty.

But Ms Chambers is not in the business of niceness. She is a bean-counter. The rising cost of health insurance in America has led to a 15 per cent increase in employee benefits for Wal-Mart - a company famed for its stinginess. Since the overweight are more likely to require medical attention, Ms Chambers is keen to get shot of them. Not with time-consuming schemes to help them to slim down, such as on-site gyms or healthy cafeterias; it is much simpler, as she explains in her memo, just to give them the cold shoulder.

"It will be far easier to attract and retain a healthier workforce than to change behaviour in an existing one," she writes. "These moves would dissuade unhealthy people from coming to work at Wal-Mart."

There is a strange circularity at work here. The main reason for America's obesity epidemic is the ubiquity of junk food - thanks, in large part, to supermarket giants such as Wal-Mart. This food is (in calorific if not nutritional terms) dirt cheap, which means it is especially popular with the poor. And Wal-Mart employees are very likely to be poor: the average full-time member of staff earns just $17,500 a year - or £9,825.

It seems an extraordinary cheek to recruit from the underclass, pay underclass wages, and then grumble when your staff display the symptoms of the underclass.

Still, at least Wal-Mart's policies are driven by straightforward profit. On this side of the Atlantic, it seems, anti-fattism is just as rife - and for no better reason than visceral prejudice.

A survey published last week by Personnel Today found that corporations routinely discriminate against the overweight. The magazine asked 2,000 "human resources professionals" to choose between two equally qualified job applicants, one fat and the other of "normal weight". A hefty 93 per cent chose the latter.

Nor were they remotely apologetic about this bigotry. On the contrary: around half justified it on the grounds that fat people lack self-discipline. More than one in 10 thought being overweight was a sackable offence, and 12 per cent said they would not want such a social pariah coming face to face with a client.

I have always been suspicious of anyone involved in "human resources" - a dehumanising piece of jargon if ever I heard one - and it's tempting to write these people off as stony-hearted corporate drones. But such views are not, alas, confined to the boardroom.

A serious Sunday paper recently ran an admiring article on the rise of the "new puritans": young people who have reacted against consumer culture by refusing to drink, smoke, buy big brands, take cheap flights, drive a fancy car - or get fat. Just like the corporations they despise, these anti-capitalist smuggypants regard weight as an indication of moral character.

"There should be really skinny entrances to McDonald's," suggested one waifish 26-year-old. "If you can't fit through the door, that would be a pretty good indication that you shouldn't go in at all."

It is, of course, preferable to be slim: I do not know a single fat person who would argue otherwise. And, to some extent, our weight may indeed be shaped by character: comfort eating - like fanatical dieting - is usually the outward expression of inner sadness.

It is, in other words, an indicator of humanity. We all have our frailties: the trouble with fat people is that theirs are too visible. "Gluttony," as Orson Welles once mourned, "is not a secret vice." The bulimics, the exercise junkies, the insomniacs, the Prozac-poppers, the new puritans - they can all keep their psychological crutches to themselves, at least at work.

Fat people may lack self-discipline in one particular area of their lives, but so does almost everyone. Would a woman who always falls for bastards, or a man who never gets round to doing the chores, be considered unfit for work? Picking on fat people is as pointless as it is unkind: you can't get human resources without human failings.