You may not think you eat a lot of corn and soybeans, but you do: 75 percent of the vegetable oils in your diet come from soy (representing 20 percent of your daily calories) and more than half of the sweeteners you consume come from corn (representing around 10 perecent of daily calories).

Food is also about pleasure, about community, about family and spirituality, about our relationship to the natural world, and about expressing our identity. As long as humans have been taking meals together, eating has been as much about culture as it has been about biology.

In the end I'm still a writer. I'm still a journalist, and my first responsibility is to my readers. That's where I have to draw the line.

We're supposed to show people how the world is, to give them the tools they need to make good decisions as citizens or consumers. Depending on what your values are - the environment, your health, animal welfare - the answers are going to be different for every person.

The growth of the American food industry will always bump up against this troublesome biological fact: Try as we might, each of us can only eat about fifteen hundred pounds of food a year. Unlike many other products - CDs, say, or shoes - there's a natural limit to how much food we each can consume without exploding. What this means for the food industry is that its natural rate of growth is somewhere around 1 percent per year - 1 percent being the annual growth rate of American population. The problem is that [the industry] won't tolerate such an anemic rate of growth.

The single greatest lesson the garden teaches is that our relationship to the planet need not be zero-sum, and that as long as the sun still shines and people still can plan and plant, think and do, we can, if we bother to try, find ways to provide for ourselves without diminishing the world.

It's been a mystery to me and a disappointment why conversation about health care reform hasn't turned more attention to the subject of food.