In the United States, when world wheat prices rise by 75 percent, as they have over the last year, it means the difference between a $2 loaf of bread and a loaf costing maybe $2.10. If, however, you live in New Delhi, those skyrocketing costs really matter: A doubling in the world price of wheat actually means that the wheat you carry home from the market to hand-grind into flour for chapatis costs twice as much. And the same is true with rice. If the world price of rice doubles, so does the price of rice in your neighborhood market in Jakarta. And so does the cost of the bowl of boiled rice on an Indonesian family’s dinner table.

Welcome to the new food economics of 2011: Prices are climbing, but the impact is not at all being felt equally. For Americans, who spend less than one-tenth of their income in the supermarket, the soaring food prices we’ve seen so far this year are an annoyance, not a calamity. But for the planet’s poorest 2 billion people, who spend 50 to 70 percent of their income on food, these soaring prices may mean going from two meals a day to one. […]