Put down that kiwi! (Do you know where it's been?)

What are the heaviest items in our diets in terms of carbon dioxide, which is cited by scientists as the main contributor to climate change?.

One candidate, The New York Times notes today (in an article headlined "Some carbon with your kiwi?''), might be the cod caught in Norway, shipped to China to be cut into filets, shipped back to Norway, only to be shipped again -- and sold to us. One reason, besides labor, that these globe-crossing, energy-wasting efforts are happening more often: they've been propped up by tax breaks. Fuel for international freight often is not taxed under trade agreements, a scenario that many economists, politicians and environmental activists say deserves reconsideration.

"We're shifting goods around the world in a way that looks really bizarre,'' the Times quoted Oxford economist Paul Watkiss as saying.

What do you think? Let us know.

By the way, here's a helpful introduction to a low-carbon diet, and a look at how, starting last Tuesday, the food-service supplier to MIT, Emmanuel College, Lesley and Cisco Systems in Boxborough has committed to cutting 25 percent of its carbon load. (A three-word hint: Ciao San Pellegrino.)