Originally, the atoms of carbon from which we're made were floating in the air, part of a carbon dioxide molecule. The only way to recruit these carbon atoms for the molecules necessary to support life-the carbohydrates, amino acids, proteins, and lipids-is by means of photosynthesis. Using sunlight as a catalyst the green cells of plants combine carbon atoms taken from the air with water and elements drawn from the soil to form the simple organic compounds that stand at the base of every food chain. It is more than a figure of speech to say that plants create life out of thin air.

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.

Once you introduce the issue to young people and suggest to them that they have the ability to vote with their forks, either by positively going for certain kinds of foods or rejecting other kinds of foods, they realize that this is a responsibility and an opportunity to shape the world a little bit by their own choices.

I get letters from classes all the time. Say it's assigned in someone's 8th grade class, and the teacher asks everyone to write a letter to me about their impressions and what they learned. So, it's incredibly gratifying to hear.

Corn is the hero of its own story, and though we humans played a crucial supporting role in its rise to world domination, it would be wrong to suggest we have been calling the shots, or acting always in our own best interests. Indeed, there is every reason to believe that corn has succeeded in domesticating us.

Every peasant cuisine has incredible ingenious tricks for getting a lot of nutrition out of a small amount of ingredients. There are people who don't have the money to invest in better food, but perhaps they have the time. There's a trade-off: The more time you're willing to put into food preparation, the less money you have to spend.

Don't ingest foods made in places where everyone is required to wear a surgical cap.