We are not presently growing anywhere near the amount of vegetables and fruit needed, however. “We estimated that just in order to meet the minimum recommendations for fruit and vegetable consumption - the five-a-day recommendation - production would have to increase by 50% by 2050,” says Springmann. If consumers do move away from meat-based diets, there will be shifts in the economics of production, potentially very large ones.

“You might have more employment in fruit and vegetable sectors, but the employment might also rely on seasonal contracts,” Springmann speculates. And for farmers who currently produce meat, a rise in veganism or vegetarianism is likely to be unsettling. “Animal proteins are 'value-added' products from the producer side of the equation,” says Jayson Lusk, meaning that they transform relatively low-cost products, like feed, into something that will sell for a higher price.

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Annika Carlsson-Kanyama, who studies the environmental impact of food in the Swedish context, says as demand for meat has declined slightly, the response from producers has not been sanguine. “Clearly in Sweden the farmers’ organisation is feeling this trend as a threat… They are not really outspoken but they have started to produce ads where they show negative pictures on the alternatives to meat, for example,” she says.

However, half of all of Sweden’s meat is imported, she points out, so reducing consumption doesn’t necessarily mean that domestic producers have to feel a hit. And she also notes that meat replacements and new, higher-protein versions of foods like pasta, using flour made from beans, are a growing industry there. “I see it as an opportunity for Swedish agriculture to start producing new products,” she says. Vegan milk made from Swedish oats, for example, made by the company Oatly, is now not only available in-country but abroad.

At any rate, with the global food system behind up to a third of greenhouse gas emissions and likely to rise as meat consumption grows precipitously in places like China, things can’t continue as they are. We can take heart in the fact that things have already shifted, Carlsson-Kanyama says, since she began her work. Attitudes are changing, just as Buckley has noticed.

“During the 90s, when I talked about my research, some people would always get very irritated,” she reflects. “People always got angry with me… they scolded me and so on. But nowadays nobody does that. It’s become accepted to say we do really have a lot of evidence that shows that eating less animal products will not only save the environment but also promote our health. I think we’ve come a long way.”

“Of course it’s a challenge to those who produce meat and dairy products. Of course that is a challenge,” she says. But for the sake of the planet and our health - not to mention pocketbooks - it may be one to consider.

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