How Much Water and Land Do Plant and Animal Foods Use?

Animal foods generally need much more land than plant foods, because animals eat feed or graze on pasture. Water is harder to compare, because it depends a lot on place and on which kind of water you count. This guide shares the main facts and the limits of the data.

How much land does farming use?

Our World in Data reports that about half of the world's ice-free and desert-free land is used for farming. The UN Food and Agriculture Organization (FAO) puts the figure near 50%. Poore and Nemecek (2018) put it at 43%. The gap comes mostly from how each source defines pasture.

The same sources give a clear picture of what that land is used for:

• Global farmland is about 4.1 billion hectares, according to Poore and Nemecek (2018).
• Almost three quarters of it is pasture. The rest is cropland.
• When pasture and feed crops are counted together, around 80% of farmland serves meat and dairy.

Where does the plant-based share fit?

Plants for people take up a much smaller share. Our World in Data shares the Poore and Nemecek estimate that beef and lamb need roughly 50 to 100 times as much land per calorie as plant alternatives. They also need roughly 50 to 100 times as much land per gram of protein as peas or tofu.

Feed matters too. Our World in Data reports that only about 48% of the world's cereals go directly to human food. About 41% goes to animal feed and 11% to biofuels.

What about the land that cannot grow crops?

This is where the story has some nuance. Mottet and colleagues (2017) estimate that about two thirds of grazing land is unsuitable for growing crops. Much of it is dry, steep or rocky. On that land, grazing animals can turn grass into food that people cannot grow in any other way.

This does not change the overall picture. But it explains why some people who care about the land still raise animals. It also shows why a single global number can hide a lot of local detail.

A thought experiment

Poore and Nemecek (2018) ran a scenario for a fully plant-based global diet. In their model, farmland would fall by about 75%, from roughly 4.1 billion hectares to about 1 billion. This is a model, not a forecast. Nobody expects the whole world to change at once.

It still shows the size of the link between diet and land. Even smaller shifts free up space. Land that is no longer farmed can recover as forest or other habitat.

What do we know about water?

Our World in Data reports that agriculture accounts for about 70% of global freshwater withdrawals, citing Gleick and colleagues (2014). The share varies by country. Many countries in South Asia, Africa and Latin America use over 80% of their withdrawals on farming. Germany and the Netherlands use under 1%.

Why is water harder to compare?

There are four reasons it is hard to give one number per food:

1. Withdrawal is not consumption. Withdrawal is water taken. Some of it returns to rivers or aquifers.
2. Blue water and green water are different. Blue water comes from rivers, lakes and groundwater. Green water is rain stored in soil. Many figures count only blue water, so rainfed systems can look cheaper than they are, or the reverse.
3. Place matters most. A liter taken from a wet region is not the same as a liter taken from a dry basin.
4. National averages hide local stress. A country can look fine while one aquifer is running low.

Because of this, we avoid giving a "liters per kilogram" table here. The numbers vary by method and source, and they can mislead. What we can say is general: crops that need irrigation in dry places put more pressure on water than crops watered by rain.

What can a home cook do?

The most useful steps are simple, and they do not require perfect knowledge.

• Eat more beans, lentils, peas, tofu and whole grains, which use less land per gram of protein.
• Waste less food. Food you throw away took land and water to grow.
• Be curious about thirsty crops in dry regions, but do not panic about any one food.
• Choose rain-fed or locally suited crops when you can, and when it is easy.

If you eat with people who eat meat, there is no need to bring up land use. A shared meal is a better start than a debate.

A note on tone

Numbers about land and water can sound like blame. They are not meant to be. They describe a food system that most of us did not design. Each person can make a few changes, and that is enough.

Frequently asked questions

Is eating plant-based always better for land use?

On average, yes, because feeding crops to people directly is more efficient than feeding them to animals first. But there are cases, such as grazing on land that cannot grow crops, where the story is more complex.

Does a plant-based diet save water?

It often reduces pressure on water, because animal foods need feed crops and drinking water. But the effect depends on the place, the crop and the type of water counted. A simple number would be misleading.

Why do sources disagree on how much land is farmed?

They define pasture in different ways. Some count all grazed land, including rough rangeland. Others count only managed grassland. The result is a range, such as 43% to 50% of habitable land.

Can grazing land be used for crops instead?

Often it cannot. Mottet and colleagues (2017) estimate that about two thirds of grazing land is unsuitable for crops. Soil, slope and climate set the limits.

Sources

• Our World in Data, Land use of diets (2021), citing Poore and Nemecek (2018) and Mottet et al. (2017): https://ourworldindata.org/land-use-diets
• Our World in Data, Water Use and Stress (2018), citing Gleick et al. (2014) and FAO AQUASTAT: https://ourworldindata.org/water-use-stress
• Our World in Data, Environmental impacts of food production, citing Poore and Nemecek (2018): https://ourworldindata.org/environmental-impacts-of-food