In the past, environmentalists have cited "food miles" as the unit by which to measure a food's impact on the environment. Their argument was the further a piece of food travelled, the more its harm to the environment. But the concept has come under scrutiny, with others nothing it's how the food is made, not how far it travels that contributes to its carbon footprint.
It's becoming trendy to eat locally and shop green, but it's easy to lose track of the ultimate goal--reducing greenhouse gasses emissions--when we get caught up in the fervor of eating local."
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