You are what you grow

A few years ago, an obesity researcher at the University of Washington named Adam Drewnowski ventured into the supermarket to solve a mystery. He wanted to figure out why it is that the most reliable predictor of obesity in America today is a person’s wealth. For most of history, after all, the poor have typically suffered from a shortage of calories, not a surfeit. So how is it that today the people with the least amount of money to spend on food are the ones most likely to be overweight?

Drewnowski gave himself a hypothetical dollar to spend, using it to purchase as many calories as he possibly could. He discovered that he could buy the most calories per dollar in the middle aisles of the supermarket, among the towering canyons of processed food and soft drink. (In the typical American supermarket, the fresh foods - dairy, meat, fish and produce - line the perimeter walls, while the imperishable packaged goods dominate the center.)

Drewnowski found that a dollar could buy 1,200 calories of cookies or potato chips but only 250 calories of carrots. Looking for something to wash down those chips, he discovered that his dollar bought 875 calories of soda but only 170 calories of orange juice.

As a rule, processed foods are more “energy dense” than fresh foods: they contain less water and fibre but more added fat and sugar, which makes them both less filling and more fattening. These particular calories also happen to be the least healthful ones in the marketplace, which is why we call the foods that contain them “junk”. Drewnowski concluded that the rules of the food game in America are organised in such a way that if you are eating on a budget, the most rational economic strategy is to eat badly - and get fat.

This perverse state of affairs is not, as you might think, the inevitable result of the free market. Compared with a bunch of carrots, a package of Twinkies, to take one iconic processed food-like substance as an example, is a highly complicated, high-tech piece of manufacture, involving no fewer than 39 ingredients, many themselves elaborately manufactured, as well as the packaging and a hefty marketing budget. So how can the supermarket possibly sell a pair of these synthetic cream-filled pseudocakes for less than a bunch of roots?

For the answer, you need look no farther than the farm bill. This resolutely unglamorous and head-hurtingly complicated piece of legislation, which comes around roughly every five years and is about to do so again, sets the rules for the American food system - indeed, to a considerable extent, for the world’s food system.

Among other things, it determines which crops will be subsidised and which will not, and in the case of the carrot and the Twinkie, the farm bill as currently written offers a lot more support to the cake than to the root. Like most processed foods, the Twinkie is basically a clever arrangement of carbohydrates and fats teased out of corn, soybeans and wheat - three of the five commodity crops that the farm bill supports, to the tune of some $25 billion a year. (Rice and cotton are the others.) For the last several decades - indeed, for about as long as the American waistline has been ballooning - US agricultural policy has been designed in such a way as to promote the overproduction of these five commodities, especially corn and soy.

That’s because the current farm bill helps commodity farmers by cutting them a cheque based on how many bushels they can grow, rather than, say, by supporting prices and limiting production, as farm bills once did. The result? A food system awash in added sugars (derived from corn) and added fats (derived mainly from soy), as well as dirt-cheap meat and milk (derived from both).

By comparison, the farm bill does almost nothing to support farmers growing fresh produce. A result of these policy choices is on stark display in your supermarket, where the real price of fruits and vegetables between 1985 and 2000 increased by nearly 40 per cent while the real price of soft drinks (aka liquid corn) declined by 23 per cent. The reason the least healthful calories in the supermarket are the cheapest is that those are the ones the farm bill encourages farmers to grow.

A public-health researcher from Mars might legitimately wonder why a nation faced with what its surgeon general has called “an epidemic” of obesity would at the same time be in the business of subsidising the production of high-fructose corn syrup. But such is the perversity of the farm bill: the nation’s agricultural policies operate at cross-purposes with its public-health objectives. And the subsidies are only part of the problem.

The farm bill helps determine what sort of food your children will have for lunch in school tomorrow. The school-lunch program began at a time when the public-health problem of America’s children was under nourishment, so feeding surplus agricultural commodities to kids seemed like a win-win strategy.

Today the problem is over nutrition, but a school lunch lady trying to prepare healthful fresh food is apt to get dinged by USDA inspectors for failing to serve enough calories; if she dishes up a lunch that includes chicken nuggets and Tater Tots, however, the inspector smiles and the reimbursements flow. The farm bill essentially treats our children as a human disposal for all the unhealthful calories that the farm bill has encouraged American farmers to overproduce.