A vegan-friendly world can prevent a devastating land use crisis
If current global food consumption habits continue without much change, humanity is heading for a major land use and availability crisis that could undermine the food supply chain, with devastating consequences for the health and well-being of billions of people, and compounding the problems caused by excessive water use. The problem is that there simply won’t be enough land available to produce the food we need. However, there is a straightforward solution to this problem: if enough people switch from meat-based to plant-based diets, the available land will be easily sufficient to produce all the food we need, because it is far more efficient to use land for producing plant foods than animal foods. This is obvious when we compare how much land is needed to produce a given quantity of a particular food, as measured by its nutritional value. For example, if we consider the calorific content:
- 119.5 square metres are needed to produce 1000 calories of beef.
- 116.7 square metres are needed to produce 1000 calories of lamb and mutton.
- 22.7 square metres are needed to produce 1000 calories of cheese.
- 14.9 square metres are needed to produce 1000 calories of dairy milk.
- 2.2 square metres are needed to produce 1000 calories of peas.
- 2.1 square metres are needed to produce 1000 calories of nuts.
- 1.4 square metres are needed to produce 1000 calories of wheat and rye.
- 0.8 square metres are needed to produce 1000 calories of rice.
- 0.7 square metres are needed to produce 1000 calories of maize.
If instead we consider the protein content:
- 184.8 square metres are needed to produce 100 grammes of lamb and mutton protein.
- 163.6 square metres are needed to produce 100 grammes of beef protein.
- 39.8 square metres are needed to produce 100 grammes of cheese protein.
- 27.1 square metres are needed to produce 100 grammes of milk protein.
- 7.9 square metres are needed to produce 100 grammes of nut protein (excluding peanuts).
- 7.3 square metres are needed to produce 100 grammes of protein from pulses.
- 4.6 square metres are needed to produce 100 grammes of protein from grains.
- 3.5 square metres are needed to produce 100 grammes of peanut protein.
- 3.4 square metres are needed to produce 100 grammes of pea protein.
These figures provide a good indication of how much more efficient plant food production is when compared to animal food production. Another way of looking at this issue is to consider the overall agricultural land use across the planet. Currently the total amount of land used for agriculture is about 4.1 billion hectares, which represents about half of all the land on Earth that is not covered by ice or desert.
Of these 4.1 billion hectares, 2.9 billion are used for animal pasture, and the remaining 1.2 billion used as cropland. But more than 500 million hectares of this cropland are used to grow animal feed, leaving just 700 million hectares that is used to grow human food directly. If everyone in the world followed a vegan diet the amount of cropland needed to produce enough food to feed everybody would be 1.0 billion hectares, a reduction of more than 75% with respect to the current agricultural land use figure of 4.1 billion hectares.
Unfortunately, although many people are switching to plant-based diets, overall meat consumption is also on the increase. This is partly driven by rising prosperity, particularly in China, but also by a growing world population. What this means is that a steadily increasing area of agricultural land will be needed to produce enough food to feed everyone. If current trends continue, then by 2050 we will have reached the point that there won’t be enough land available to feed everybody. The only way to avoid this crisis is if there is a major shift towards plant-based diets.