That's the question explored in the New York Times article excerpted below, and the short answer is, it's more complicated than that. A lot more complicated. The local food, or locavore, movement has so much momentum that some of the food glitterati have declared that such food is better than organic.
But now comes a team of researchers from the University of California, Davis, who have started asking provocative questions about the carbon footprint of food. Those questions threaten to undermine some of the feel-good locavore story line, not to mention my weekend forays for produce. (A carbon footprint is a measure of the impact of human activities on the environment in terms of the amount of greenhouse gases produced.)
While the research is not yet complete, Tom Tomich, director of the University of California Sustainable Agriculture Research and Education Program, said the fact that something is local doesn’t necessarily mean that it is better, environmentally speaking.
The distance that food travels from farm to plate is certainly important, he says, but so is how food is packaged, how it is grown, how it is processed and how it is transported to market.
Consider strawberries. If mass producers of strawberries ship their product to Chicago by truck, the fuel cost of transporting each carton of strawberries is relatively small, since it is tucked into the back along with thousands of others.
But if a farmer sells his strawberries at local farmers’ markets in California, he ferries a much smaller amount by pickup truck to each individual market. Which one is better for the environment?
Mr. Tomich said a strawberry distributor did the math on the back of an envelope and concluded that the Chicago-bound berries used less energy for transport. Maybe. Regardless, the story raises valid questions.
An Iowa State University study in 2003 found that most produce travels about 1,500 miles before it arrives in Iowa homes. But as the strawberry story suggests, some of it creates higher amounts of greenhouse gases than others. Transporting food by container ship or rail is relatively energy efficient. Shipping it by air or a 25-year-old pickup is not.
It gets stickier. If a low-carbon diet is your goal, Mr. Tomich suggests, it may be more effective to change your diet than to focus on eating local. After all, a plant-based diet tends to have a much smaller carbon footprint than a diet that includes meat. That is because a pound of steak requires many more pounds of grain as feed — and all the carbon emissions associated with that, from fertilizers that are derived from fossil fuels to the fuel for the combines used for the harvest, he said.
And if you insist on eating meat, as I do, then perhaps it’s better for the environment to eat poultry rather than red meat and grass-fed rather than grain-fed. Mr. Tomich’s team is trying to sort that out.
Here are a couple of other puzzlers: Are canned tomatoes a better environmental choice in the winter than fresh tomatoes from abroad? If a product that contains heavy packaging reduces the amount of food waste, is that a better choice than one that is lightly packed and spoils quicker?
Gail Feenstra, a food system analyst at the Davis campus, says her group hopes the research will help consumers decide if buying local is better than buying organic food that has traveled hundreds of miles. “Maybe you can buy organic within a certain geographic range, and outside of that the trade-offs won’t work anymore,” Ms. Feenstra said.
At some point, the ethical maze can make you dizzy. But there was one line of inquiry from the California researchers that hit particularly close to home: the carbon impact of shoppers themselves.
Some people walk or take the subway to buy their groceries and then compost what they don’t use. But, let’s face it, most of us drive and toss the leftovers into the garbage disposal or the garbage can. In doing so, we may be contributing nearly a quarter of the greenhouse gases associated with our food, research has shown.
But now comes a team of researchers from the University of California, Davis, who have started asking provocative questions about the carbon footprint of food. Those questions threaten to undermine some of the feel-good locavore story line, not to mention my weekend forays for produce. (A carbon footprint is a measure of the impact of human activities on the environment in terms of the amount of greenhouse gases produced.)
While the research is not yet complete, Tom Tomich, director of the University of California Sustainable Agriculture Research and Education Program, said the fact that something is local doesn’t necessarily mean that it is better, environmentally speaking.
The distance that food travels from farm to plate is certainly important, he says, but so is how food is packaged, how it is grown, how it is processed and how it is transported to market.
Consider strawberries. If mass producers of strawberries ship their product to Chicago by truck, the fuel cost of transporting each carton of strawberries is relatively small, since it is tucked into the back along with thousands of others.
But if a farmer sells his strawberries at local farmers’ markets in California, he ferries a much smaller amount by pickup truck to each individual market. Which one is better for the environment?
Mr. Tomich said a strawberry distributor did the math on the back of an envelope and concluded that the Chicago-bound berries used less energy for transport. Maybe. Regardless, the story raises valid questions.
An Iowa State University study in 2003 found that most produce travels about 1,500 miles before it arrives in Iowa homes. But as the strawberry story suggests, some of it creates higher amounts of greenhouse gases than others. Transporting food by container ship or rail is relatively energy efficient. Shipping it by air or a 25-year-old pickup is not.
It gets stickier. If a low-carbon diet is your goal, Mr. Tomich suggests, it may be more effective to change your diet than to focus on eating local. After all, a plant-based diet tends to have a much smaller carbon footprint than a diet that includes meat. That is because a pound of steak requires many more pounds of grain as feed — and all the carbon emissions associated with that, from fertilizers that are derived from fossil fuels to the fuel for the combines used for the harvest, he said.
And if you insist on eating meat, as I do, then perhaps it’s better for the environment to eat poultry rather than red meat and grass-fed rather than grain-fed. Mr. Tomich’s team is trying to sort that out.
Here are a couple of other puzzlers: Are canned tomatoes a better environmental choice in the winter than fresh tomatoes from abroad? If a product that contains heavy packaging reduces the amount of food waste, is that a better choice than one that is lightly packed and spoils quicker?
Gail Feenstra, a food system analyst at the Davis campus, says her group hopes the research will help consumers decide if buying local is better than buying organic food that has traveled hundreds of miles. “Maybe you can buy organic within a certain geographic range, and outside of that the trade-offs won’t work anymore,” Ms. Feenstra said.
At some point, the ethical maze can make you dizzy. But there was one line of inquiry from the California researchers that hit particularly close to home: the carbon impact of shoppers themselves.
Some people walk or take the subway to buy their groceries and then compost what they don’t use. But, let’s face it, most of us drive and toss the leftovers into the garbage disposal or the garbage can. In doing so, we may be contributing nearly a quarter of the greenhouse gases associated with our food, research has shown.
Interfaith Power and Light is a religious response to global warming with chapters in 25 states and Greater Washington, D.C. Find a link to your local chapter at http://www.theregenerationproject.org/State.
Find discounts on energy saving products at http://www.shopipl.org/
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