If you are not currently reading The Omnivore's Dilemma: A Natural History of Four Meals by Michael Pollan: stop everything immediately and get yourself a copy. It's that good, and that important.
I've been reading it for a week now, and had expected to write a review when I'd finished but it's taken me longer than I anticipated to get through it. There's so much to chew on I find I just stop reading mid-paragraph to think about everything he's saying. And really, it's so eye-opening that it's foolish for me to wait until I'm done to tell you: if you care about food, read this book.
Here's a small sampling from some of the pages I've dog-eared:
Very simply, we subsidize high-fructose corn syrup in this country, but not carrots. While the surgeon general is raising alarms over the epidemic of obesity, the president is signing farm bills designed to keep the river of cheap corn flowing, guaranteeing that the cheapest calories in the supermarket will continue to be the unhealthiest. (p 108)
"The organic label is a marketing tool," Secretary [of Agriculture] Glickman said. "It is not a statement about food safety. Nor is 'organic' a value judgment about nutrition or quality."…Some intriguing recent research suggests otherwise. (p 179)
Today it takes between seven and ten calories of fossil fuel energy to deliver one calorie of food energy to an American plate….Yet growing the food is the least of it: only a fifth of the total energy used to feed us is consumed on the farm; the rest is spent processing the food and moving it around. (p 183)
[T]here are no pigtails in industrial hog production. Farmers "dock," or snip off, the tails at birth, a practice that makes a certain twisted sense if you follow the logic of industrial efficiency on a hog farm. Piglets…are weaned from their mothers ten days after birth (compared with thirteen weeks in nature)…[b]ut this premature weaning leaves the pigs with a lifelong craving to suck and chew, a need they gratify in confinement by biting the tail of the animal in front of them. (p 218)
Our food system depends on consumers' not knowing much about it beyond the price disclosed by the checkout scanner. Cheapness and ignorance are mutually reinforcing. And it's a short way from not knowing who's at the other end of your food chain to not caring…[o]f course, the global economy couldn't very well function without this wall of ignorance and the indifference it breeds. (p 245)
So fight the indifference, and fight the ignorance. Go read The Omnivore's Dilemma. No book has changed the way I think about food and food production more than this.