Is it just a coincidence that as the portion of our income spent on food has declined, spending on health care has soared? In 1960 Americans spent 17.5 percent of their income on food and 5.2 percent of national income on health care. Since then, those numbers have flipped: Spending on food has fallen to 9.9 percent, while spending on heath care has climbed to 16 percent of national income. I have to think that by spending a little more on healthier food we could reduce the amount we have to spend on heath care.

I made the unexpected but happy discovery that the answer to several of the questions that most occupied me was in fact one and the same: Cook.

This, for many people, is what's most offensive about hunting—to some, disgusting: that it encourages, or allows, us not only to kill but to take a certain pleasure in killing

A natural historian is somebody who looks at something in terms of its relationship to the rest of the natural world. You look at things ecologically. When you see a cow on a feedlot, you don't just see a cow; you see a cow that is eating certain food. You follow that food and that food takes you back to a corn field.

Okinawa, one of the longest-lived and healthiest populations in the world, practice a principle they call hara hachi bu: Eat until you are 80 percent full.

There are things we know and things we don't know about food. But there are certain basic things we do know, and that's what I've tried to build these rules on.

Don't eat anything your great-grandmother wouldn't recognize as food. Don't eat anything with more than five ingredients, or ingredients you can't pronounce.