Where your (ultraprocessed) food comes from

If you want to see the birthplace of America’s ultraprocessed diet, take a drive through the upper Midwest in high summer. Before long, you’ll be hypnotized by the shimmering green blanket of corn and soybeans that fuels our industrial food system. Radiating from their geographical and spiritual epicenter in Iowa, these two crops cover nearly two-thirds of U.S. cropland — an area equal to 1.7 Californias.

These crops are the raw materials the food industry transforms into the dizzying array of products that fill hundreds of millions of bellies every day. They provide feed for the livestock whose meat and dairy make fast-food chains and deli counters hum, and their derivatives provide a huge proportion of the fat, sweeteners, and other additives that make processed treats so hard to resist. All told, corn and soybean are the ultimate source for nearly half the calories the average American consumes each day.

Why all the love for just two crops? It’s not overly reductive to say it boils down to a half century of intentional federal farm policy. In the years after World War II, U.S. farms in the upper Midwest underwent an industrial revolution. Diesel-powered tractors replaced horse-powered plows, and synthetic nitrogen fertilizers replaced their manure. Farmers no longer reliant on horses no longer needed to grow crops to feed them — and thus oats and other “small grains” began to vanish from the landscape. In their place, corn and high-protein soybeans – key components of cheap livestock feed — gained favor as the meat business began to rapidly industrialize. 

These advances represented heavy new expenses for farmers, but U.S. Department of Agriculture programs encouraged their adoption with financial assistance that enabled big purchases like tractors as well as smaller annual purchases of newly improved hybrid corn seeds. As a result of this tech boom, yields — the amount of corn and soybeans produced per acre — increased steadily.

Yet even as the government encouraged farmers to adopt these bin-busting technologies, it also tried to avoid overproduction — which lowered prices — through a set of policies called “supply management,” one of which paid farmers to fallow a portion of their land the year after a bumper harvest. The system worked well enough for some 25 years, but in the early 1970s the federal government — aggressively lobbied by agribusiness companies eager to sell ever more seeds, pesticides, fertilizers, and farm machinery — shifted course and USDA chief Earl Butz famously urged farmers to plant “fencerow to fencerow.” The result was an orgy of overproduction. Vast gluts of corn and soybeans began to pile up, and prices plunged. Between 1974 and 1984, the inflation-adjusted price of both corn and soybeans fell by more than half. Prices have remained at or near historic lows ever since.

Farmers might have been expected to give up on corn and soybeans as prices waned, but the federal government was also offering farmers direct payments and, later, subsidized crop insurance — in which taxpayers pay 63%of a farmer’s crop insurance policy premium — to keep them planting those crops. In Iowa alone, between 1995 and 2023, farmers received $24.6 billion in subsidy payments, mostly to corn and soybean growers. Indeed, corn and soybeans became even more entrenched on U.S. cropland, rising from a combined share of around 45%of all acreage in 1980 to 60%today. 

By the early 1980s, giant grain-trading companies like Archer Daniels Midland (ADM) and Cargill were scrambling to find profitable markets for this bounty. Meanwhile, wider changes in corporate America, with companies more squarely focused on delivering maximum profit to shareholders, were also transforming the processed food industry. 

But maintaining brisk quarterly revenue growth was a tough order for major food companies because overall food demand in a wealthy, developed country like the U.S. is fairly static, tracking the mild rate of population growth. But the industry had an answer: flood the zone with crave-worthy and convenient new products that would take market share from competitors. The impact of this move — documented and mocked most recently by Jerry Seinfeld in Unfrosted — was fast and furious. 

According to Marion Nestle (see our Q&A with her), author of Food Politics: How the Food Industry Influences Nutrition and Health, the number of calories available per person in the food supply increased dramatically following Butz’s fencerow-to-fencerow edict, from around 3,200 calories in 1980 to roughly 4,000 in 2000, where it stands today. That amounts to “twice what the country needs on average,” she told me. Of course, now the industry was dealing with “more food than anybody could possibly want or need, and they had to figure out ways to sell more food more quickly,” says Nestle. “And they did it by putting food everywhere” — from vending machines and college libraries to gas stations and 7-Elevens.

Cornstarch and soy lecithin, byproducts of corn and soybean processing, quickly became go-to additives, serving as readily available, low-cost emulsifiers and thickeners that made the industry’s novel products sing on consumers’ palates. But perhaps these crops’ greatest value was the ease with which they could be transformed into cheap sweeteners and fats, which provide two of the three pillars of the food industry’s strategy to sell ultraprocessed foods, as documented in Michael Moss’ 2013 blockbuster Salt Sugar Fat: How the Food Giants Hooked Us.

In the 1970s, ADM ramped up production of high-fructose corn syrup (HFCS), and in about 10 years, the soda industry had fully embraced the sweetener. Soon, HFCS had a foothold in baked goods, packaged desserts, and other products as manufacturers learned the ingredient could boost the palatability of their offerings at a lower cost than cane sugar, which it quickly came to displace. U.S. per-capita consumption of corn sweeteners nearly doubled between 1970 and 1980, and then doubled again over the next 15 years, according to USDA figures. 

Then there’s fat. Adding fat to a recipe improves mouthfeel and stimulates appetite, as Moss makes clear in Salt Sugar Fat; and the industry started doing so with a vengeance as it scrambled to roll out blockbuster products. The concurrent rise of cheap, plentiful soybean oil meant that companies could add more of this flavor enhancer without adding much to their costs. The USDA estimates that between 1970 and 2005, U.S. per-capita consumption of vegetable oil — largely made from corn or soybeans — jumped by 9%. Most of that came in the form of fat added to processed food. Over the same period, consumption of animal fat dropped 16%, but because of the vegetable oil boom, overall fat consumption rose a startling 63%. 

So as you gape at that display of corn and soybeans glittering on the Midwestern summer landscape, remember that it’s the highly subsidized raw material that the food industry transforms into one of the most unhealthy diets the world has ever seen in times of abundance. But if government policy, driven by corporate interests, is what triggered the rise of our ultraprocessed food environment, then theoretically at least, better food and farm policies are possible, too. 

Recently, the political stars have shifted to make such change seem possible. After Trump established the Make America Healthy Again Commission, newly confirmed Health and Human Services Secretary Robert F. Kennedy, Jr. gathered department employees and announced he’d be scrutinizing potential causes for the nation’s “drastic rise in chronic disease.” Among the possible factors he said that he would investigate was ultraprocessed foods. So far, there have been no real outspoken critics of this target among lawmakers. That category boasts a notoriously long shelf life, but its time at the center of our diets could be running out.