By concentrating on one element of Michael Pollan’s work explored in Food, Inc., corn production, and adding humor to the chilling information it conveys, King Corn provides a more engaging process-driven narrative that attempts to reveal why corn now comprises such a large percentage of the American diet. Dennis Harvey’s Variety review provides a positive perspective of the film, asserting that Cheney and Ellis’s “low-key antics, their affectionate regard for the small-town milieu, some delightful stop-motion animation and an excellent rootsy soundtrack by the WoWz all make "King Corn" go down easy, even if you might regard your burger, fries and Coke with suspicion afterward.”
Ann Hornaday of the Washington Post agrees, asserting that the film is “gorgeously filmed in digital video and Super-8, using clever stop-motion corn kernel animation and a lyrical score by the "anti-folk" band the WoWz.” According to Hornaday, too, with help from its “engaging guides,” Cheney and Ellis, "King Corn takes what could be a tiresome agri-civics lesson and delivers a lively, funny, sad and even poetic treatise on the reality behind America's cherished self-image as the breadbasket of the world.” Andrew O’Hehir of Salon.com also highlights the lessons of King Corn but concludes, “This information arrives via a graceful and frequently humorous film that captures the idiosyncrasies of its characters and never hectors.”
Through their naïve attempts to grow corn in Greene, Iowa, their ancestral home, Ian Cheney and Curt Ellis do reveal the extent to which corn has entered the American diet, so much so that, when tested, their bodies chemistries both include more than fifty percent corn. To expose how corn has become an ingredient in nearly every food source found in the supermarket, Cheney and Ellis plant, grow, and harvest one acre of corn. During the process, the two learn not only about the corn-growing process, but also about the farm subsidies that support the corn industry, especially since changes in subsidy legislation during the Nixon administration.
Like Food, Inc., King Corn relies on nostalgia as a rhetorical tool, contrasting the industrialized corn production expected today—with powerful fertilizer, government aid, and genetically modified seed to support it—with traditional farming techniques practiced in the same area when their great-grandparents farmed the land. By primarily maintaining this focus on corn production and its entrance into the American diet through high fructose corn syrup and other corn-based ingredients found in almost every food item in the supermarket and the fast food restaurant, the film successfully demonstrates the power of corn.