“There are around 120 ‘eco-labels’ on the market, from Fair Trade to organic and Rainforest Alliance Certified,” he says. “Until we have a single, unified metric, it is really difficult for consumers to make those food judgments themselves.”
Clark says it is important that carbon doesn’t become the only measure used to determine food’s environmental impact. “We need to take a holistic perspective,” he says. Besides carbon, we should consider how the food we eat impacts water, land and biodiversity, he says, noting that foods with a high carbon footprint often require a large amount of land for production.
This isn’t always the case, he adds. Wild-caught fisheries, for example, don’t use large amounts of land or freshwater, but can release a lot of CO2 when they drag weighted nets across the ocean floor, and have devastating impacts on ocean ecosystems through overfishing and seafloor destruction. (Read more: Can eating fish ever be sustainable?)
Miers agrees that carbon labels only tell us a fraction of the story, but says it’s a useful tool that gets people to start thinking about food’s climate impact. “But if we just focus on carbon, we are really at risk of oversimplifying a complex subject which is nature and shooting ourselves in the foot,” she says, adding that Wahaca is also focusing on other environmental issues beyond greenhouse gas emissions, including sourcing ingredients from regenerative farmers who do not use any herbicides or fertilisers to boost soil health (which further enables it to trap more carbon).
“We’re not here to bash people over the head,” says Miers. “It’s just about giving people information. It’s not about telling people what they can or can’t eat.”
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