Sixty years ago, books about food tended to be cheerful affairs, presaging infinite abundance. Their illustrations featured beaming mothers lowering a platter of roast beef or a leg of mutton onto the Sunday table. The farmer atop his mighty combine harvester was the icon of Life magazine as much as of Soviet agitprop. These days we know better. The books and pictures are dystopian. The prairies have been tilled into sterility, the underlying water tables drained by the insensate requirements of mass meat production. The homesteads of the small farmer lie crushed under the iron heel of agribusiness. The feedlot beef is lethally marbled, the old double-sided Barnsley chop with its spinal cord banned by law. This very month, Americans are trembling at the spectre of salmonella in their tomatoes. The virtuous young decline most forms of nourishment deemed palatable by their elders. The icon now is the organic farmer hauling produce to the farmers' market by bio-diesel-powered light truck.

Both Paul Roberts and Felicity Lawrence operate from this gloomy and mostly accurate perspective. They have done plenty of homework and it is scarcely their fault if a lot of the corporate infamies and statistics that smoulder angrily in their pages often have a somewhat familiar reek. After all, from the moment that victuallers and provisioners in the Napoleonic wars pioneered the organisation of the mass production line and modern methods of food preservation, the stage was set for the annihilation of both time and space in the matter of food production, marketing and consumption. The Chicago packing houses were ripe targets a century ago; the railroad barons were being savaged by populists for ruining farmers earlier still.

Roberts, a reporter from The Seattle Times, starts us off at an exalted moment in the history of balanced diet, with Australopithecus healthily subsisting on “fruits, leaves, larvae and bugs” along with modest gobbets of carrion. “His large teeth, powerful jaws and oversize gut were all adapted to coarse, fibrous plant matter...Even his small size - he stood barely 4ft tall and weighed 40lb - was ideal for harvesting fruit among the branches.” Three million years later, we arrive with Roberts at the far end of an inexorably descending arc, with 400-lb, low-income specimens of Hom sap, swollen by excessive intake of calories, their guts compromised by lack of fibre, many of them diabetic, draped over their scooters, harvesting the supermarket aisles for sugar, salt and fat-saturated snacks that will hike up their blood pressure, clog their arteries and propel them to early graves.

The prime villains in both books are the corporate food baronies. As Lawrence puts it briskly, “Modern food production involves processes that, quite apart from having little care for real nutrition, drive people off the land, stimulate migration, increase inequalities and the depth of poverty, are corrosive of society, and depend on extravagant use of natural resources, from water to oil to land, that are running out. The politics of food is in other words not the art of shopping but the politics of modern globalised capitalism itself.”

Roberts doesn't put it quite so brusquely, but identifies global giants such as Cargill (grain) and Tyson (chicken and fish) and the American retail chains such as Kroger, Albertsons, Safeway and above all Wal-Mart as imposing ever lower prices on their suppliers, thus requiring ever more stringent productivity and hence lower profit margins, thus forcing all but the most amply capitalised farm enterprises to the wall.

As a title, The End of Food seems excessively glib and merely an echo of Roberts's previous book, The End of Oil, until one realises that he buys fairly heavily into Malthus and the Rev Thomas's notorious predictions in the early 19th century that population would inevitably outstrip food supply. One of Malthus's strategies to avert this threat to the well-to-do was to locate the poor in marshland in the expectation that pestilence would kill them off. Shrinking from such tasteless strategies, the Rockefellers and other millionaires concentrated their philanthropic investments on population control and improved productivity, best symbolised by the “green revolution” of manipulated seed strains. The anti-Malthusians argued that political reform would produce stable societies, equitable income distribution and hence declining pressure to produce large families.

Roberts sets little store by political reform, and his modern version of Malthus's useful pestilences are prospective epidemics - striking rich and poor alike - such as avian flu. In Roberts's estimation, the bizarre diets, genetic manipulations and hideous close confinements that are associated with the mass food production of cows, pigs and chickens make such epidemics inevitable.

Lawrence is less of a Malthusian and less gloomy overall. She doesn't see any swift reversal of the downward slide, but has hope that the public appetite for organic food, linked to new forms of distribution such as community-supported agriculture, food boxes and the like, will impel shifts to the better. She exhibits no faith in any initiatives by political parties, captives of the food giants and the sort of conventional thinking imperishably symbolised by the older George Bush's budget director, Richard G Darman, who bellowed furiously in 1990 that “Americans did not fight and win the wars of the 20th century to make the world safe for green vegetables”. He was defending his boss's publicly expressed distaste for broccoli.

Shifts can certainly be surpisingly rapid in the ways food is produced, distributed and consumed. The mightiest of the food giants can respond swiftly to a kick on the shins. So can the smaller speciality stores. Turn back to Elizabeth David's English Bread and Yeast Cookery, published 31 years ago. Page after page relates her gloom at the difficulty in getting good bread flour, or decent salt. These days the supermarkets surrender valuable shelf space to top-quality flours from organic producers. Fleur de Sel de Guérande, admittedly at high prices, nestles next to Saxa. This is progress, as was McDonald's shift, under intense pressure from environmental groups, to better boxes for its fast food.

So there are advances in public tastes and demands, even as Chinese-owned soya-bean fields chew up the Amazon's rainforest, and commercial fleets strip the oceans of their fish. Absurdities trot in the wake of good intentions. I feed my horses on hay grown on a pasture half a mile up river from my house. Since the hayfield, though never sprayed or fertilised, is not officially classed as organic, the manure from my horses, if spread anwhere in my garden or orchard, would render my apples ineligible for an “organic” label. My recourse would be to import “organic” hay by truck from Modesto, 330 miles south of me, in California's Central Valley, at a cost of several thousand dollars plus a couple of hundred gallons of diesel fuel vented over the landscape. The term “organic” becomes extremely malleable in the hands of a state legislator with an ag-industry lobbyist standing at his elbow, chequebook in hand.

The saddest story of all is land reform, and here, as Roberts and Lawrence seem to concede, there isn't much of a silver lining, although the sky is getting a little lighter in Latin America. Land barons are tenacious. Governments and international bureaucracies have a matchless tendency to do the wrong thing. All the same, excessive doom-saying doesn't get one far. The benign food movements of today, such as they are, had their roots in a more optimistic time, half a century ago. As manure, optimism is usually productive.

The End of Food by Paul Roberts
Bloomsbury £12.99 pp416 Buy the book from Books First £11.69 including fee delivery
Eat Your Heart out by Felicity Lawrence
Penguin £8.99 pp352 Buy the book from Books First £8.54 including free delivery

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