King Corn / Corn reigns supreme over all other U.S. crops, appearing, in various forms, in 70 percent of all foods consumed by Americans–in flours, binders, additives, cereals, cooking oils and, most ubiquitous of all, high fructose corn syrup. It has replaced simple grasses as feed for U.S. cattle, a dangerous practice that, beyond a certain point, can sicken and kill the animals. Corn-fed beef, in turn, has more than eight times the saturated fat of grass-and-hay-fed beef.

Fascinated by these facts and other alarming info, two young men–Curt Ellis and Ian Cheney–decide to rent some Iowa farmland and grow one acre of corn, harvest it and then follow its progress from silo to refinery to industry to various markets in various unrecognizable forms. Following the dicta of such farming methods (genetically-modified seeds, strong herbicides and nitrogen fertilizers) the two men, just out of college, watch, off and on, their one acre from planting (in January) to harvest (late October), and then receive the second half of the crop’s $28 government subsidy (per acre). (Until earlier this year, corn growers lost money and subsisted only by such subsidies.)

While their crop matures, Cheney and Ellis interview various experts and/or middlemen in the game of researching and marketing corn additives and liquid forms. Speaking candidly are farmers, academics, refinery officials, scientists and government representatives. One worker tells them, and it’s later confirmed, that cattle fed on the traditional strain of corn (with much less protein than other strains) will sicken and die from acidosis after l20 days of such feeding. Antibiotics are added to the corn to stave off cattle illness, usually with success. (Seventy percent of U.S. antibiotics are insinuated into cattle feed.)

What the novice farmers further learn is that the U.S. Department of Agriculture radically shifted its crop polices in the mid-l970s–from controlled growth to more-is-better growth, with corn the economic solution to farming and food costs. In cattle feed, there was a shift from range grazing to confined feedlots, where cattle fatten more quickly because they cannot move around. The detectable saturated fat in a beefsteak from closed pens is nearly nine times as that from a range grazer, and grass does not sicken cattle as corn can if not treated with antibiotics.

It was then, the l970s, that corn syrup began to surpass sugar as a sweetener, particularly in canned juices and fruit–and, of course, soft drinks.

What about the two young men’s attempts to follow their corn from field to table? It proved impossible: they were not allowed admittance to most refineries and production facilities. (They were forced to make homemade corn syrup in order to understand the process.) It was difficult to find comprehensive research on the astronomical rise of diabetes from the ’70s. Many scientists would talk off the cuff but would not give official sanction for use of those (apparently incomplete) statistics. (Some studies show clearly that corn syrup is one of the main culprits in America’s current phenomenal rise in childhood obesity.) America’s favorite sandwich–the hamburger–contains more saturated fat (and antibiotics) than its l970s incarnation, and its usual companions–french fries–are more often than not cooked in corn oil.

King Corn is an even-handed documentary that impresses more and more as its investigations, from Iowa to Colorado to New York, accumulate more detail. The film, directed by Aaron Woolf, seems to have such a simple conceit: grow an acre of corn and find out as much as we can about it. What finally emerges is a country at peril in terms of nutrition, obesity and largely uncontrolled use of corn in human and animal foodstuff, it’s enough to kill your appetite.