It’s a tricky thing to grow enough food for a ballooning population without destroying the natural world. And when I say a tricky thing, I mean it’s one of the greatest challenges humanity has ever faced.
Luckily for us, it is theoretically possible, and the easiest way to get there is by drastically cutting down on meat.
But it doesn’t have to be this way. Researchers recently modelled how the world could feed itself in 2050 without converting any current forests into agriculture. They tested the outcome under 500 different scenarios that varied according to realistic assumptions on future yields, the area needed for farming, livestock feed and human diets. They found that “deforestation is not a biophysical necessity”.
“While a wide range of feasible options to feed a no-deforestation world were found, many only worked under certain circumstances,” said Karl-Heinz Erb, lead author of the study, published in Nature Communications.
For example, meat-heavy diets were not compatible with lower yields similar to those under organic farming, or under the potential negative effects of climate change. Of all the variables involved, the feasibility of feeding the world with no deforestation is more dependent on what we are eating, than on how well we farm.
“The only diet found to work with all future possible scenarios of yield and cropland area, including 100% organic agriculture, was a plant-based one,” Erb said.
Even better: if we all woke up vegan in 2050, we would require less cropland than we did in the year 2000. This could allow us to “reforest” an area around the size of the entire Amazon rainforest – somehow fitting considering 70-80% of deforestation in the Amazon is due to the livestock industry.
In second place, the vegetarian diet was compatible with 94% of future no-deforestation scenarios. Going veggie would also save on cropland, allowing for an area around the size of India to return to nature.
This land-saving makes sense when considering the conversion rate between the grain that we could have directly consumed but instead feed to livestock. For example, in the US, it takes an astounding 25kg of grain to produce 1kg of beef, pigs require a grain to meat ratio of 9:1 and chickens, relatively less wasteful, are 3:1. As renowned ecologist Hugh Possingham put it: “Just stop feeding grain to animals – don’t eat something that ate something that you could have eaten.”
Plant-based diets are particularly impressive when compared to those that are rich in meat, which would require a 50% increase in global cropland area by 2050. In order to achieve this with a chance of no-deforestation, we’d have to convert lots of pasture to cropland and substantially increase yields, likely through using chemicals. But both conversion and intensification generally degrade ecosystems and lead to less biodiversity.
Overall the new study found that a meat-eater requires at least double the resources of a vegan or vegetarian.