In the 2012 documentary The Fruit Hunters, there’s a shot of the produce section of a grocery store. The camera pans across an expanse of fruit-laden tables, all piled several feet high with apples, pears, potatoes, and much, much more. “Abundance,” the narrator intones.
The incredible abundance spotlighted in this brief scene is an achievement of the modern food supply chain, a sprawling, complex structure that spans the entire planet, yet is largely unseen by consumers. Most of us only encounter the literal fruits of this marvel, taking for granted that we can get bananas, kiwis, and lettuce at any time of the year, no matter where in the U.S. we live. This is, of course, unnatural. It’s the result of relentless engineering and optimization, the industrialization of food made possible through technology, logistics, and scale.
A Global Chain
The whole thing begins with the farm, which is often a large-scale growing operation and may specialize in just one kind of crop. After the farm harvests the crop, it goes from processors and packers to wholesalers, then to retailers, and finally, to household consumers — “with transportation taking place between each link,” notes Dr. Sean Clark, associate professor of agriculture and natural resources at Berea College. Transportation runs up a major amount of greenhouse gas emissions, and it’s an aspect of the supply chain that food activists have zeroed in on.
A short food supply chain with just two links — farm, consumer — sounds appealingly simple and wholesome, for us and the environment. Certainly, reducing links in the chain can reduce the miles (and therefore, the carbon emissions) that food travels. But for all the attention that food miles have gotten, transportation does not typically account for the bulk of a given food’s environmental toll.
“’How far does food travel?’ is the wrong question,” says Dr. Justin Gardner, associate professor of agribusiness at Middle Tennessee State University. Unless the food is grown in your backyard, it must travel some distance via some mode of transportation. “We should instead look at efficiency.”
It turns out that the massive scale and specialization of the food supply chain makes it very efficient, relatively speaking. A lot of food can travel using a comparatively small amount of fuel when it is commercially transported by ship, train, plane, or truck.
The Real Culprit
Most of the greenhouse gas emissions of food are emitted long before we ever see a single morsel. Production accounted for a whopping 83 percent of food’s total greenhouse gas emissions. Transportation for the entire supply chain (from farm to consumer and everything in between) accounted for just 11 percent. “In attempting to minimize dietary environmental impact, food miles are only a small part of it. Eating lower on the ecological food chain — more plants and fewer animals — can make a big impact,” says Clark.
That’s because the production of meat (red meat, in particular) emits more greenhouse gases than any other form of food. Animals must be continually fed, often for several years, so meat racks up emissions associated with its own food, the feed. There’s the nitrous oxide, a greenhouse gas 300 times more potent than carbon dioxide, emitted from the fertilizer applied to animal feed, the carbon dioxide from the transportation of the feed to the animals, and then more nitrous oxide is emitted during the breakdown of the animals’ manure. Cattle are also one of the largest sources of methane, a greenhouse gas 20 times more potent than carbon dioxide. Lastly, on top of its enormous production emissions, meat also happens to tot up numerous food miles because of its extensive supply chain: Live animals undergo more processing than produce, and given the space requirements of raising cattle, the farms are relatively remote. The production emissions of fruits and vegetables can also outweigh transportation emissions, especially if the produce is grown in less-than-ideal conditions. Not everything can be grown locally in a sustainable way. The growing conditions needed to produce a crop might not be found nearby or during certain seasons. Often, “We can buy produce from countries that can produce more efficiently than we can,” says Gardner.
A Sustainable Diet
Since production accounts for the majority of your food’s environmental impact, choosing food based on its production requirements can have a much greater effect than only choosing local foods. One study noted that only a “21-24% reduction in red meat consumption, shifted to chicken, fish, or an average vegetarian diet lacking dairy, would achieve the same reduction” in greenhouse gas emissions as choosing foods with zero food miles! Not everyone can go vegetarian full-time, but skipping meat on occasion can decrease demand for it. Try participating in Meatless Monday, or choosing poultry over red meat a few times a week.
While food transportation isn’t the biggest culprit of food’s greenhouse gas emissions, choosing local produce that’s grown in-season is still a great way to green your food choices. There are other reasons to buy locally and seasonally, too, such as supporting your local economy and finding more flavorful produce. Even though the food supply chain is huge and complex, our many small actions in aggregate can make a difference.