In the docu-blockbuster-cum-human-experiment Super Size Me, released in British cinemas over the weekend, New York filmmaker Morgan Spurlock eats nothing but McDonald's meals three times a day for a month. He's won widespread praise for pushing his body to the limit - he goes from fit to fat, gets bad skin, has mood swings, and in one scene, having spent 22 minutes eating a Super Size Double Quarterpounder Meal, pukes it up out of his car window - all for the apparently worthy cause of showing Americans 'the real price they are paying for their "addiction" to fast food' (1).

Sounds radical, right, taking on the Golden Arches of America and charging them with making poor folk sick and miserable by forcefeeding them junk? In fact, Super Size Me, like so many other anti-McDonald's campaigns, comes with a generous side order of snobbery. Its real target is the people who eat in McDonald's - the apparently stupid, fat, unthinking masses who scoff Big Macs without even asking to see a nutritional and calorie breakdown first. Spurlock and his ilk might hate McDonald's, but they seem to loathe the McMasses even more.

Spurlock's venture looks to me like a sparkier, more irreverent and updated version of 'Mass Observation', that notorious study of the masses carried out by anthropologist Tom Harrisson in the 1930s, where a team of middle-class observers 'mingled with the natives' and collected data on everything from football pools to dirty jokes to armpit hygiene - all recounted in inglorious detail in John Carey's The Intellectuals and the Masses (2). But Spurlock goes a step further; he doesn't only mingle with the natives but becomes one of them, transforming his body into what he imagines the average American's body to be like.

The film starts by showing us that Spurlock is something of a model citizen. Before he begins his 30-day binge on nothing-but-MaccyD's he goes to a GP, a gastroenterologist and a physical fitness instructor for a series of tests. They decree that he's fit, able, has a low cholesterol, a very good Body Mass Index and is in 'great shape'. As a Manhattanite he also walks everywhere, rather than relying on a car like the rest of fat America, and even has a vegan chef for a girlfriend (referred to as 'Healthy Chef Alex'). In short, he's a Good American in one of the few ways that you can measure being a Good American in our post-political, post-moral times: he's healthy.

Then he crosses over to the other side.... The rules are that he can only eat what is available over the counter at McDonald's; he has to reduce the amount he walks to a maximum of 5,000 steps a day, to reflect how little the average American apparently waddles around; and, most importantly, if he's offered the option of Super-Sizing his meal (which comes with seven ounces of fries and a 42-ounce coke) he has to say yes - the assumption being that the kind of people who frequent McDonald's are so feckless that when the spotty teen behind the counter mentions the SS-phrase they are powerless to resist (especially if they're from Texas, one of the Fattest States of America according to Spurlock, where he was most often asked 'You wanna Super Size that?').

So Spurlock grosses out in order to see what it's like to be one of those gross Americans. Fellow American Cosmo Landesman of The Sunday Times praises him for taking a 'kamikaze dive into the gargantuan blubber-gut and buttock-mountain serial heart-killer and cholesterol free fall that is obese America's fast-food blowout' (3). But Spurlock only becomes a cartoon Yank, a fat lazy blob living down to his own and others' prejudices. No one in their right mind would eat just McDonald's every day; most of those interviewed in the film say they eat fast food once or twice a week. As some experts have pointed out, Spurlock probably became ill because his 30-day diet was so unvaried. The same would have happened if he'd only eaten foie gras or fruit or some other 'good' food for a month.

The lower orders are often lambasted for their lack of food-consciousness today

It is striking how morally loaded some of the discussions about food are. In one of the funnier scenes, Healthy Chef Alex - a holistic health counsellor who believes in 'integrating appropriate food choices and lifestyle options' - tries to coax Spurlock away from the 'corrupt' world of meat-eating and towards a Good Life of nuts and lentils (4). Spurlock visits a school where the pupils are calm and attentive and claims that it's a result of their eating healthy school dinners from the Natural Ovens Bakery rather than the sugary fare stuffed down kids' throats in other districts. Food, it seems, is not only about taste, enjoyment or nutrition; what we eat apparently reveals something of our moral character.

In this, Super Size Me chimes with the times. On both sides of the Atlantic there's a large portion of moralising in the panics over obesity, school dinners, junk-food-guzzling and the rest. What is presented as straightforward medical concern for our health and wellbeing is often really a judgement on lifestyle and behaviour - and especially the lifestyle and behaviour of a certain class of people. In debates about 'bad' foods (McDonald's), fast foods (microwave meals), and fat mums in clingy leggings who make their kids fat too by feeding them 'junk', there's a barely concealed contempt for the working classes, who are presumed to be lazy, feckless and not sufficiently concerned with healthy cooking and fitness. It's there in the terminology: they are seen as 'junk' people.

It isn't fashionable to pass strictly moral judgements in our 'anything goes' age - and certainly no one would do what Tom Harrisson did in the 1930s, discussing the masses as 'scientific specimens'. Instead, at a time when few are willing to say what kind of lifestyle is right and wrong, the lower orders are lambasted for their eating habits and lack of food-consciousness - all in the name of helping to transform them into better healthy happy citizens, of course. The moral divide today isn't between the educated few and the uneducated mob as it was for Harrisson and co, but between those who eat healthily and those who (allegedly) don't, between good foodies and bad burger-eaters.

Such cheap McMoralism is best summed up in a leaflet produced by McSpotlight, an anti-McDonald's campaign group that encourages local communities in the UK to resist the building of new McDonald's restaurants. Under the heading 'Litter, noise and smells', the leaflet says McDonald's will 'result in noise and disturbances at all hours....the smell from the kitchens, from waste storage and from litter disgarded [sic] by customers may become offensive and attract vermin' (5). What these campaigns really hate about MaccyD's is the kind of people it attracts; in McSpotlight's leaflet, offensive 'customers' and 'vermin' all merge into a mishmash cautionary tale about the apparent horrors of the modern McDonald's. Meanwhile, inside my local McDonald's, normal-looking families can be seen enjoying their Happy Meals....

Of course McDonald's, like every other big corporation, mistreats its workers and puts the maximisation of profits first. But in the faux class war between anti-McDonald's campaigners and the McMasses, I'm on the side of the 'happy eaters' every time.

(1) Review of Super Size Me, Cosmo Landesman, The Sunday Times, 12 September 2004 (registration required)

(2) The Intellectuals and the Masses: Pride and Prejudice Among the Literary Intelligentsia 1880-1939, Faber and Faber, 1992

(3) Review of Super Size Me, Cosmo Landesman, The Sunday Times, 12 September 2004 (registration required)

(4) See the Healthy Chef Alex website

(5) See What's wrong with the McDonald's planning application?, McSpotlight