Buy local, shrink the distance food travels, save the planet. The locavore movement has captured a lot of fans. To their credit, they are highlighting the problems with industrialized food. But a lot of them are making a big mistake. By focusing on transportation, they overlook other energy-hogging factors in food production.
Take lamb. A 2006 academic study (funded by the New Zealand government) discovered that it made more environmental sense for a Londoner to buy lamb shipped from New Zealand than to buy lamb raised in the U.K. This finding is counterintuitive–if you’re only counting food miles. But New Zealand lamb is raised on pastures with a small carbon footprint, whereas most English lamb is produced under intensive factory-like conditions with a big carbon footprint. This disparity overwhelms domestic lamb’s advantage in transportation energy.
New Zealand lamb is not exceptional. Take a close look at water usage, fertilizer types, processing methods and packaging techniques and you discover that factors other than shipping far outweigh the energy it takes to transport food. One analysis, by Rich Pirog of the Leopold Center for Sustainable Agriculture, showed that transportation accounts for only 11% of food’s carbon footprint. A fourth of the energy required to produce food is expended in the consumer’s kitchen. Still more energy is consumed per meal in a restaurant, since restaurants throw away most of their leftovers.
Locavores argue that buying local food supports an area’s farmers and, in turn, strengthens the community. Fair enough. Left unacknowledged, however, is the fact that it also hurts farmers in other parts of the world. The U.K. buys most of its green beans from Kenya. While it’s true that the beans almost always arrive in airplanes–the form of transportation that consumes the most energy–it’s also true that a campaign to shame English consumers with small airplane stickers affixed to flown-in produce threatens the livelihood of 1.5 million sub-Saharan farmers.
Another chink in the locavores‘ armor involves the way food miles are calculated. To choose a locally grown apple over an apple trucked in from across the country might seem easy. But this decision ignores economies of scale. To take an extreme example, a shipper sending a truck with 2,000 apples over 2,000 miles would consume the same amount of fuel per apple as a local farmer who takes a pickup 50 miles to sell 50 apples at his stall at the green market. The critical measure here is not food miles but apples per gallon.
The one big problem with thinking beyond food miles is that it’s hard to get the information you need. Ethically concerned consumers know very little about processing practices, water availability, packaging waste and fertilizer application. This is an opportunity for watchdog groups. They should make life-cycle carbon counts available to shoppers.
Until our food system becomes more transparent, there is one thing you can do to shrink the carbon footprint of your dinner: Take the meat off your plate. No matter how you slice it, it takes more energy to bring meat, as opposed to plants, to the table. It takes 6 pounds of grain to make a pound of chicken and 10 to 16 pounds to make a pound of beef. That difference translates into big differences in inputs. It requires 2,400 liters of water to make a burger and only 13 liters to grow a tomato. A majority of the water in the American West goes toward the production of pigs, chickens and cattle.
The average American eats 273 pounds of meat a year. Give up red meat once a week and you’ll save as much energy as if the only food miles in your diet were the distance to the nearest truck farmer.
If you want to make a statement, ride your bike to the farmer’s market. If you want to reduce greenhouse gases, become a vegetarian.