But he learned a few things. Any changes we can make to make the food system more sustainable, less reliant on oil and more on sun, will yield impressive dividends in all three of these areas. "I also learned something else very hopeful -- that all food, every calorie you have ever eaten, comes ultimately from the sun." As long as the sun is still shining, theoretically it should be possible to figure out a way to feed ourselves from the sun rather than from those oil fields.

"To understand how we got here, I want to take you back to the past, present, and give you a look at the future of our food system." Look back to before WWII. We have images of what farming was like back then: these are the images still used to sell food to us today, the small family farms with red roof barns. Now this is just a literary conceit, but it's how things used to be. "It was a very straightforward solar and human-powered system." The farmer planted crops, raised livestock, and they contributed to one another's health. "The line from sun to crops to animals to farmer to us was fairly straight and direct." It wasn't terribly productive but it was an ecologically efficient system.

A calorie is a unit of energy. Pre-WWII, a single calorie of food energy introduced into the food system (in the form of diesel, to run tractors) yielded 2 calories of edible food. But this wasn't productive enough for us after WWII. We had a baby boom, a population that wanted to binge on all of the foods that had been rationed during the war, and we had factories that needed more workers. "We wanted to get more food from fewer farmers. And we figured out how to do it." We figured out how to take the munitions industry, which relied on ammonium nitrate -- you use it for bombs but we decided to use it for fertilizers. We converted nerve gas research into pesticides, and munitions research into fertilizer.

"We figured out ways to take cheap oil and make farming more productive. But we also needed changes in Washington at the policy level, and we got these most dramatically in the 70s." Nixon's agriculture secretary convinced farmers to grow as much of monoculture crops as possible. "Get big, or get out," he said, and he focused attention on corn and soy.

Understand: this is not the same kind of corn you buy at a farmstand around here in August or September, or the soybeans you get when you buy edamame. They are inedible off the field. They are industrial materials which can be broken down into corn syrup and so forth, but mostly they are feed for animals. "This changed the diversified farming system into something that looked more like a factory," with inputs of fuel and outputs of monoculture crops which require processing. "We took a natural system and turned it into something which closely resembled a factory."

And it worked -- amazingly well. We got an amazing amount of calories off the land. Before WWII a farmer could feed 20 of us, afterward a farmer could feed 150 people. The benefit to us is that food has gotten a lot cheaper. In 1910 we spent a quarter of our income to feed ourselves; today it's under 10%. That's less than anybody who has ever lived and less than anybody anywhere in the world. Today you can walk into a fast food store and for less than you earn at minimum wage in one hour, you can walk out with thousands of "arguably tasty" calories.

But we have to be clear-eyed about the costs. "Cheap food is incredibly expensive."

The first expense is, in order to grow food this way, we need huge amounts of fossil fuel. That's what we've replaced all that human energy with. "Every step in this process, we're applying more petroleum to the system." To grow the food, process it, move the food around. "When you buy sustainable salmon in a restaurant here, from Alaska, the odds are good that it's been flown to China to be fileted and then flown back here to be eaten by you." Half the lobster harvested in this state goes up to Canada to be processed, then frozen and sold all over the world. There's a lot of oil in this system.

Pollan holds up a very fresh double quarter-pounder with cheese, from McDonald's. "I want to show you how much oil goes into producing this," he says, opening up a dark plastic water bottle. Oil is in the fertilizer, and in the pesticides. He fills an eight-ounce glass with dark liquid. Then a second one, for the processing and moving around. And a third glass of eight ounces, and then two more ounces in a fourth glass. "26 ounces of oil to produce this burger. It's kind of disgusting, isn't it?"

CC photo by Kris Krüg. Coal, a McD burger, and 26 ounces of "oil."

As we gape, he adds, offhand, "--chocolate syrup." (Ahaha! Well, it's thick and dark; it makes a fine oil substitute, for visual purposes.) It takes ten calories of fossil fuel to produce one calorie of food energy. We're losing nine calories for every calorie we yield to eat.

"You know that old saying of grandma's, that you can pay the grocer or you can pay the doctor? We've chosen to pay the doctor." We're eating 500 more calories per day than we used to; we're about 17lbs fatter than we used to be. Two-thirds of us are overweight, one-third of us are obese. One in three people born in 2000 will get type II diabetes, which shortens the lifespan by an average of seven years, which means this generation will be the first in American history to have a shorter life expectancy than their parents. Four of our top-ten killers are linked to diet. "The health care crisis is a euphemism for problems induced by the American diet."

And people who are trying to feed themselves on a limited budget have a real problem here. If you've seen Food, Inc. you've met the Orozco's of Baldwin, CA. (Pollan shows us a clip from that movie, showing a woman talking about how much money they have to spend on pills for her diabetic husband -- more than $100 per pill. "We can pay for his medicine to be healthy, or buying vegetables to be healthy, so which one should we do?") What a choice to make, between diabetes medication and fresh produce! But in this country, "the rational thing to do is to buy unhealthy calories; we subsidize the calories by subsidizing corn." Products made with high-fructose corn syrup and hydrogenated corn oils are the cheap calories.

Go into a supermarket with a dollar, he says, and conduct a treasure hunt for calories to see how many calories you can get for a dollar. You can get 1200 calories of snack foods for that dollar -- or 250 calories of broccoli or carrots. "This is the result of the way we subsidize food in this country."

The third and last cost of the system he wants to address is the cost to our ecosystem. The burger has quite a carbon footprint. Thirteen pounds of carbon into the air, which is the equivalent of burning seven pounds of coal. "I hope I've driven home the point that our meat eating is one of the most important contributors we make to climate change. A vegan in a Hummer has a lighter carbon footprint than a beef eater in a Prius!"

Another source of pollution coming off of this industry is feedlot pollution. Every cow in the feedlot produces as much manure as 20-40 people produce in a single day. 150,000 cows generate as much waste as the 3,000,000 people in Chicago -- but the people in Chicago have to treat their waste. But the clean water and air act doesn't apply to feedlots. So these vast lakes of sewage just sit there, leaking pollution of all kinds into the ecosystems. These feedlots are the biggest source of pollution in the country.

"That's the bad news, and there's plenty of it. But I want to talk about some good news" -- some farmers he's had the pleasure of meeting. The first is Joel Salatin, a visionary farmer in the Shenandoah Valley of Virginia. (You'll read about him in the Omnivore's Dilemma.) "This is a post-industrial farm," based on a sophisticated understanding of plants, animals, and how they interact. Joel grows in a complex polycultural rotation sometimes called permaculture. It's a largely self-contained system. He grows grassfed cattle and chickens. The cows spend one day in a pasture; then he moves them on to the next pasture, waits three days, and tows in his portable chicken coop. The chickens are free-range; they fan out in the field and make a beeline for the cow patties, because their favorite food -- grubs -- are in the manure. (As a side note: the CSA to which Ethan and I have belonged for the last fifteen years has been doing this for years. I love watching the eggmobile moving around the farm!)

The chickens, of course, also defecate in the fields -- and their manure is fertilizer for grasses, so a few days after they've been moved out of the field, the field is fertile again.

"I asked Joel, what kind of farmer are you -- a chicken farmer, a beef farmer, a rabbit farmer? He said, I'm a grass farmer. I didn't get it; we don't eat grass." But Salatin explained that grass is the solar collector. The sun feeds the grass; the grass feeds cattle, who can digest it; the cattle feed the chickens; the chickens feed the grasses; and the animals are feeding us. Joel Salatin has 100 acres of grass which yields him 40,000 pounds of beef, 30,000 pounds of pork, 25,000 dozen eggs, 20,000 chickens, 1,000 turkeys and 1,000 rabbits. He uses some diesel for his trucks and some corn for his chickens. But for every calorie going into the system, there are hundreds if not thousands coming out.

Another visionary farmer is Will Allen, who we'll meet later today. "He's doing an interesting riff on polycultural farming in the cities." Pay attention to the energy flows in his systems too, Pollan tells us.

"The question is, can you do this on a big scale? Can you do solar farming in the Midwest?" In Argentina there are farms that dwarf ours -- 15,000 acres -- and they've pulled it off. They'll do eight-eyar rotations: five years of cattle, then plow the pastures and do three years of grain (wheat, sorghum, corn, sunflowers) -- and they can do that without any nitrogen fertilizers, because the cattle have fertilized the land, and they can do it without pesticides too.

"I had an epiphany when I was on Joel's farm." Joel made Pollan get down on his belly and "meet the grasses," and explained what was going on under the soil. "I had this revelation about our relationship not just to food but to nature in general." Most of us have a tragic sense of our relationship with nature: we think it's a zero-sum game, that in need for us to get what we need, nature must be diminished. "But that may not necessarily be true."

All plants balance roots and shoots. When they lose leaf mass, they shed a comparable amount of root mass. Those roots are effectively digested by the soil: worms, insects, bacteria, fungi eat them and turn them into new soil. This is how soil is created. "I had no idea," Pollan tells us. "What that tells me is that the end of a year in a farm like Joel's, or the ones in Argentina, he has taken all of that food off the land and there is more soil, not less; more biodiversity not less; more fertility, not less. You see? It need not be a zero-sum game as long as the sun shines and we have new energy coming in. That was the most heartening thing I'd learned in 20 years."

"So how do we get there? That's the hard question." How do we change the industrial system? We need new policis. We need to replace the incentives for farmers to grow corn and soy; we need a Food Bill which has the interests of eaters and farmers equally in mind. We need to incentivize farmers to diversify, to use their land the way Joel is doing, to move away from monocultures. "We can do that, but make no mistake, it will take a powerful political movement," because the agroindustrial complex will fight it.

We need to work, Pollan says, on re-regionalizing the food system. Encourage local food economies to form! This will help us improve access to good food in inner cities and in our "food deserts." Multicropping and diversification is key, and building markets for local food will help with that.

"We are deeply implicated in this system. We expect food to be fast, cheap, and easy. Unless we make changes in our own behavior, start voting with our forks, this isn't going to happen." If we start eating real food again -- if we go to the Farmer's Market instead of the supermarket -- this change can happen. "Consumers voting with their forks are creators of these alternative food systems."

"I've spent the last couple of years trying to answer the supposedly complex question of what we should eat if we're concerned about our health," Pollan says. "I realized I can boil it all down to 3 sentences, 7 words: Eat food. Not too much. Mostly plants." It's easier said than done, he notes. Increasingly our supermarkets and restaurants are full of substances that "don't deserve to be dignified" with the word "food." Focus on quality rather than quantity, he says. And if all of America went meatless one day a week, it would be the equivalent of taking 20,000,000 cars off the road.

Three other revolutionary things we can do: 1) plant a garden. "If you invest seventy dollars in a home garden you can yield $600 worth of produce in a year." Organic produce isn't expensive if you grow it yourself. Our non-productive land could be feeding us and giving us exercise without using fossil fuels at all!

2) Get back in the kitchen and cook. "Corporations...don't cook very well," he says -- they use too much salt, sugar, and fat. The only way to get control of our diet and our food system back is by cooking again and involving our families in that.

And 3) Eat meals! Eat food at tables with other people! "This doesn't sound radical, but it has become that." Twenty percent of our food is eaten in the car, in front of a screen, on the run. "Food isn't just fuel; it's about communion," he says. "Bring back the meal as the sacred communal activity it is."

"I don't know what our food system is going to look like in 5-10 years, but I'm confident it's going to change." We're going to run out of cheap oil and probably all oil. We can't continue to spew greenhouses gases like this. "But as long as we have visionary farmers, we will figrue out how to do this. And as long as the sun still shines, there's one free lunch in this universe. It's called photosynthesis. As long as we still have that..." We need to get our industrial system off of oil, he says -- "and if one area can be re-solarized, surely it is lunch."