Don't eat any foods you've ever seen advertised on television.

I'm not talking about having to consult Julia Child before you can take a pot off the rack. I think that's something we can all do more and do better.

But carbon 13 [the carbon from corn] doesn't lie, and researchers who have compared the isotopes in the flesh or hair of Americans to those in the same tissues of Mexicans report that it is now we in the North who are the true people of corn.... Compared to us, Mexicans today consume a far more varied carbon diet: the animals they eat still eat grass (until recently, Mexicans regarded feeding corn to livestock as a sacrilege); much of their protein comes from legumes; and they still sweeten their beverages with cane sugar. So that's us: processed corn, walking.

But human deciding what to eat without professional guidance - something they have been doing with notable success since coming down out of the trees - is seriously unprofitable if you're a food company, a definite career loser if you're nutritionist, and just plain boring if you're a newspaper editor or reporter.

Meat is a tremendous environmental challenge. It contributes enormous amounts of greenhouse gas, especially beef eating.

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.

Studies show that organically grown crops produce more of the things (ascorbic acid, lycopenes, resveratrol, flavonols in general, etc) that our bodies need and also have less toxic residue. Science is still catching up with this. J. Agric. Food. Chem. Vol. 51, no. 5, 2003.