The bottom line: Totally local farming can’t totally sustain our lifestyles. And this isn’t totally clear from the coverage.

There may be other, bigger problems with the underlying theory behind Slow Food’s version of sustainability. A handful of its favorite causes include food that is fairly traded, organic, and locally produced. You can muster evidence—as The Economist did two years ago—that each of these might actually harm the environment and the food producers they aim to protect.

How? “Fair trade” ensures a subsidy on the wages food producers earn: the extra cash could encourage the overproduction that makes it so difficult to earn a living wage farming in the first place. This brings prices back down and hurts the producers that aren’t assured of fair trade subsidies. Farming “organically,” that is, with natural fertilizer that lacks yield-improving chemicals, produces less food per acre used. On a broad enough scale, such farming would divert more uncultivated land to agriculture. The Economist surmises that some of this land could very well come from rainforests.

Even the idea of burning less fossil fuel in food transportation, which seems reasonable enough, ignores other energy sources involved in food production. A study (pdf) at Lincoln University in New Zealand showed that, because of comparative climate advantage, it actually takes less aggregate energy to grow apples in New Zealand and ship them to the U.K. than it does to grow apples in the U.K. and sell them locally. Similarly, if you’re drinking wine in New York, it might be more carbon-efficient to pick Bordeaux over Napa—the former is shipped by boat, which uses less energy than the truck that takes the latter cross-country. (For a very good assessment of the difficulties inherent in calculating carbon emissions, see Michael Specter’s recent article in The New Yorker.) On the local level, what if you have to drive further to get to your farmer’s market than to your supermarket? Does it cancel out the environmental savings of local production if enough people take that trip?

Covering Slow Food presents a dual challenge. Once you’ve spent about a thousand words grappling with what this movement is and does, it’s easy to overlook the question: “Does it work?” Especially since all signs point to: “It’s too soon to tell.”

Kathy Gilsinan is a writer in New York.