With farm-to-table on the lips of every serious foodie, and salmonella and E. coli scares radiating through the larger food-buying public, America needs Food, Inc. as a first step in changing its eating habits as surely as it needed An Inconvenient Truth to put down the Hummer keys and lower the thermostat. This muckraking doc may feel like familiar territory to anyone who’s visited an urban eatery of late or cracked a Michael Pollan (The Omnivore’s Dilemma) or Eric Schlosser (Fast Food Nation) book. (Both writers appear on-camera and are behind-the-scenes contributors to the film.) Depending upon your perspective and knowledge of current food politics, director Robert Kenner’s film will be a wallow in well-trod material or a serious wake-up call.

Food, Inc. opens with the rather shocking sight of food guru Schlosser — who has exposed some of the more unpleasant aspects of the meatpacking industry, like the virtual guarantee of fecal matter in most ground beef — biting into an enormous burger at a nondescript greasy spoon. Despite his serious PC-cred alerting Americans to the health and environmental consequences of fast food fare, Schlosser also asserts his regular guy status, instantly humanizing and democratizing Food, Inc. for viewers who may not swallow its criticism of our food industrial complex whole hog.

Food, Inc. is a comprehensive indictment of what’s wrong with the modern food industry. American food is now produced in a factory-style, assembly line system that privileges ease and profit over health. In the process, Food, Inc. argues, all sorts of nastiness ensues: sick and artificially engineered animals, abuse of animals, exploitation of immigrant labor, dangerous chemicals and bacteria in our food, and unhealthy, obesity-generating Frankenfood. Countering the notion that food politics are just the province of Subaru-driving neo-bohos, one of the most persuasive advocates for a turn away from factory farming, to small farms is the 21st century’s Joel Salatin, whose Virginia farmboy cred comes in his casual slaughter of free-range chickens the old-fashioned way. This is not a film asking its viewers to give up meat or the pleasures of food, just one asking them to consider the current corporate enterprise that serves up tainted, sickly, hormone- and antibiotic-packed beef and chicken for our table. People like Salatin, who brims with integrity and passion, are contrasted with controversial agricultural biotechnology behemoths like Monsanto, a manufacturer of copyrighted, genetically-engineered seeds that lays claim to the most basic element of food production.

Criss-crossing America, Kenner captures massive chicken farms where the beasts are kept in airless, dark, rank buildings where they will grow in an absurdly abbreviated amount of time into grocery store-ready products. Some may find such revelations positively naive. Food, Inc., for instance, shows slaughterhouses and chicken farms as cruel, morbid places where animals are rushed to slaughter in the most expedient and cheapest manner possible. But how exactly did consumers think those chickens and moo-cows wound up wrapped in plastic in their grocer’s freezer? None of those birds or bovines volunteered for the job, after all.

While the physical evidence of slaughterhouse cruelty and unsanitary conditions are admittedly disgusting, there are also more insidious horrors afoot in the vegetable kingdom. Food, Inc. details a vicious circle in which cheap, plentiful corn has come to dominate our dinner plates. Kenner shows how subsidized corn used in cheap animal feed and food filler (corn syrup, anyone?) has led to a wealth of problems including tubby Americans and a rise in E. coli (resulting from infections in cows unable to digest corn feed). It’s hard to argue with the tragedies enabled by the food industry detailed in this film, like the death of 2-year-old Kevin Kowalcyk from an E. coli-tainted hamburger.

Americans who trust in the FDA, the Department of Agriculture, or big business food giants like Monsanto, Tyson, Perdue, or Smithfield will be the most shocked by this doc and what it reveals of irresponsible, bullying industry practices. Food, Inc. makes a very convincing point that our health and welfare have been steamrolled by the deep pockets of an increasingly small number of food corporations.

In the end, Food, Inc., perhaps recognizing the major bummer it has laid on viewers, offers some hints for making better choices: buy organic, become a locavore. And there is also good news afoot when the same super corporations that can wreck our diets and health, decide instead to get on the organic bandwagon. Even Wal-Mart now embraces organic food. The times, they are a-changin’. But as Food, Inc. suggests, those changes may not be happening quickly enough.