Banish ‘Eat Local’ From Your Environmental Playbook
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“What is more carbon-friendly: British beef or [imported] avocados?”
If you care about your environmental impact, you’ve likely asked a question like this before. And you might be excused for thinking the local food is the correct answer. Like much in the world of climate science, though, it is not always that straightforward.
Put on the spot for a quick answer at the assembly, Modi Mwatsama, a food systems expert at the Wellcome Trust, told me that she shied away from giving a definitive ruling. It depends “on a lot of factors,” she said, before adding that “transparency” would help people make such decisions.
That is all true. But there is also a clear answer, albeit a counter-intuitive one: “Eating local” is “one of the most misguided pieces of advice,” writes Hannah Ritchie of the University of Oxford and research group Our World in Data. It is “a recommendation you hear often—even from prominent sources, including the United Nations,” she adds.
In an analysis published last week, Ritchie finds that transport’s contribution to any food’s overall carbon footprint is tiny. “For most food products, it accounts for less than 10%” Ritchie concluded, based on data collected from 38,000 commercial farms in 119 countries.
For beef from herds grown for meat, transport makes up only an average of 0.5% of its emissions. Each kilogram of beef produces 60 kg of carbon dioxide-equivalent emissions (CO2e), the majority of which comes from the methane that cows belch when alive.
Across the complete supply chain, each kilogram of avocados produces 2.5 kg of CO2e emissions. Of that, transport costs are less than 10%. Importing Mexican avocados to the UK generates 0.21 kg of CO2e.
Such is beef’s carbon impact that, in the US, a consumer who eats vegetables instead of one day’s worth of beef calories would have a greater impact on reducing emissions than buying all food from local sources, according to a 2008 study.
Of course, there are complexities. While in most cases eating locally can cut carbon emissions marginally, and may have other benefits for the local economy and people’s connection to nature, in some cases it has the opposite effect. A 2009 study found that growing lettuce in the UK in winter months requires three to eight times as much energy as importing it from Spain.
A new analysis from Ritchie, published today, shows the recommendation stands even in face of “sustainable meats” that are supposed to have a lower overall environmental impact, including fewer emissions. The most carbon-friendly beef still produces at least 9 kg of CO2e per kg of the meat (the worst produces as much as 109 kg). In comparison, equivalent proteins from tofu would produce between 1 kg and 3.5 kg of CO2e.
The real takeaway from the research is that 1 kg of animal-based foods generate between 10 times and 50 times as much greenhouse-gas impact as plant-based products. Within animal products, beef, lamb and cheese have, respectively, 10 times, 4 times and 3 times as much carbon impact as pork and poultry does.
“Regardless of where you get your beef or lamb from, substituting with chicken and pork is likely to reduce your carbon footprint,” writes Ritchie. “If you want a lower-carbon diet, eating less meat is nearly always better than eating the most sustainable meat.”
The choices matter. A 2018 study found that the world cannot hit climate goals without large reductions in global meat consumption. So replacing meat with imported avocados is the carbon-friendly choice—and locally grown potatoes are even better.
Diving Deeper: Food and climate
- “All milk alternatives are far better for the planet than dairy.” Within the alternatives, skip almond and coconut, choose oat or soya instead. (The Guardian, Jan. 2020)
- Meat-free burgers turn climate concerns into a sales pitch. (Bloomberg, Nov. 2019)
- Plant-based meats are taking off, and could create a radically different and environmentally friendlier food chain. (The Economist, October 2019)
- What’s your diet’s carbon footprint? Use the calculator to find out. (BBC, August 2019)
- Palm oil has devastating environmental impacts. The story of how we got hooked. (The Guardian, Feb. 2019)
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