Food Miles: Do They Really Matter?

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Photo by NatalieMaynor/Flickr CC


Thanks to Dick Jackson, chair of environmental sciences at the UCLA School of Public Health, for sending me the latest paper arguing that food miles --the distances foods travel before they get to you--make no difference to climate change. Eating less meat, say the authors, is what counts. Here's the abstract of the report:

Despite significant recent public concern and media attention to the environmental impacts of food, few studies in the United States have systematically compared the life-cycle greenhouse gas (GHG) emissions associated with food production against long-distance distribution, aka "food-miles." We find that although food is transported long distances in general (1640 km delivery and 6760 km life-cycle supply chain on average) the GHG emissions associated with food are dominated by the production phase, contributing 83% of the average U.S. household's 8.1 t CO2e/yr footprint for food consumption. Transportation as a whole represents only 11% of life-cycle GHG emissions, and final delivery from producer to retail contributes only 4%. Different food groups exhibit a large range in GHG-intensity; on average, red meat is around 150% more GHG-intensive than chicken or fish. Thus, we suggest that dietary shift can be a more effective means of lowering an average household's food-related climate footprint than "buying local." Shifting less than one day per week's worth of calories from red meat and dairy products to chicken, fish, eggs, or a vegetable-based diet achieves more GHG reduction than buying all locally sourced food.

Never mind the assumptions on which such estimates are based. I have no idea whether they make sense. But before jumping to interpret this paper as an argument against the value of local food, Jackson suggests that we think about the other, perhaps less tangible, benefits of local food production.

He is a transportation expert, so he particularly emphasizes reductions in air pollution, noise, congestion, paving, heat, and the removal of trees. On the personal side, the benefits include more physical activity, "social capital" (the conversations and other transactions between consumers and farmers), income that stays in the community, and--not least--food that is fresher and tastes better.

I've always thought that the real benefits of local food production were in building and preserving communities. I like having farms within easy access of where I live and I like knowing the people who produce my food. If local food doesn't make climate change worse and maybe even helps a bit, that's just icing on the cake. Or am I missing something here?

Marion Nestle is a professor in the Department of Nutrition, Food Studies, and Public Health at New York University. She is the author of Food Politics, Safe Food, What to Eat, and Pet Food Politics.