Plant based diet impact on environment – Savings of 3 billion hectares of agricultural land

In a nutshell

Agriculture accounts for half of the world’s habitable land, and most of this is dedicated to raising dairy and meat animals. There are two sources of feed for livestock: grazing lands and land where crops, such as soy and cereals, are grown. What would be the effect of adopting a plant-based diet on our agricultural land use?

It has been suggested that a shift to a whole food plant-based diet would reduce global agricultural land use by 75%. Land used for grazing and crops could be reduced resulting in a large reduction in agricultural land use. There is also evidence that there is a much greater impact on health from cutting out beef and dairy (by substituting healthy food of plant-based diet).

Deforestation driven by agriculture

Deforestation and the loss of biodiversity are caused by the expansion of agricultural land.

In the world, agricultural land constitutes half of all ice- and desert-free land. It is mostly used for raising livestock. The amount of land needed for meat and dairy production stretches from Alaska to Tierra del Fuego.

Plant-based alternatives don’t require as much land to produce a kilocalorie as beef or lamb. The chart illustrates this. In addition, beef and lamb require almost 100 times more land than peas or tofu to produce a gram of protein.

There is no doubt that dairy farms and sheep farms are not the same as crop farms. There are pasturelands and steep hills where it is difficult to grow crops, and where livestock can be raised. Crops cannot be grown on two-thirds of pastures. 

In this case, we need to ask if we shouldn’t stop using it for agriculture altogether. It would be beneficial for biodiversity and carbon sequestration to restore natural vegetation and ecosystems to these lands.

There is concern over how much food can be grown on the remaining cropland. Researchers have discovered that we can feed everyone in the world a nutritious diet on existing croplands, but only if we shift to a plant-based diet.

Diets rich in plants require less cropland

Land use of Different diets

By shifting to a more plant-based diet, we would not only require less agricultural land, but also less cropland. Perhaps it goes against our instincts: if we replaced meat and dairy with beans, peas, tofu and cereals, wouldn’t we need to expand cropland?

Let’s examine why this isn’t true. This chart shows how much agricultural land the world would need to feed everyone. Joseph Poore and Thomas Nemecek studied global food systems for the largest meta-analysis to date. According to the global average diet in 2010, the top bar represents the current land use. 

It can be seen that nearly three-quarters of the land in this area is used as pastureland, the rest goes to crops. Animal feed is produced on around 80% of all agricultural land if we combine pasture and cropland.

Plant-based diets have a significant impact on how much land is needed. We would be eating more crops if we ate less meat and dairy. In the following bar chart, we can see that the ‘human food’ component of cropland would increase while the land used for animal feed would decrease.

Researchers estimate that our total agricultural land use would shrink from 4.1 billion hectares to 1 billion hectares if the whole world adopted a vegan diet. It is a reduction of 75%. That’s the size of North America and Brazil combined.

Importantly, large land use reductions can be achieved without a fully vegan diet. It would free up pasture land if beef, mutton and dairy were eliminated from the agricultural land use. In addition to pastures, it also decreases cropland use.

A key conclusion from this research is that reducing beef and dairy consumption (by eating plant-based foods instead) has a much greater impact on health.

Humans consume less than half of the world’s cereals

Is it possible to produce more crops for human consumption with less cropland? Looking at the bigger picture of how much crop we produce and how it is used reveals the answer.

We can see in the chart what cereals are used for around the world. It is distributed into three categories: direct human food (rice, oats, wheat, bread, etc. that we eat); animal feed; and industrial uses (mainly biofuels). 

Humans consume less than half of the world’s cereals – only 48%. 41% is used for animal feed, and 11% is used for biofuels. 

The share of food for human consumption is even lower in many countries. This is evident from the map. In most countries across Europe, less than one-third of cereal production is used for human consumption, and only 10% in the US.

The use of cereals for animal feed and biofuels is not limited to cereals. The same can be said for most oil crops. The percentage of soy used in human foods such as tofu, tempeh, soy milk and other substitutes is only 7% here. In addition to soybean meal used for animal food, most of the rest is used to produce soybean oil. However, animal feed dominates the economic value of these co-products.

Livestock produces nutrient-dense protein but wastes a lot of energy and protein

Humans consume meat and dairy products that are made from the grain fed to animals, as well as the grains fed to animals. Nonetheless, this process is very inefficient when it comes to calories and total protein. A high-quality, micronutrient-rich protein is produced by animals. An animal’s energy is not entirely used to produce meat, milk or eggs. The majority of these are simply used for keeping the animal alive. The same is true for us: the majority of calories we consume are used to maintain our life and body weight. We gain weight only when we eat too much. 

Various animal products are compared in these charts for their energy and protein content. We can calculate how much of the calories or grams of protein we feed livestock becomes meat and milk later on. An example is beef, which uses about 2% of its energy. In other words, you can feed a cow 100 kcal and get only 2 kcal of meat for that. Our analysis shows that cows are the least resource-efficient, followed by lambs, pigs, and poultry. Smaller animals are more efficient as a rule of thumb. 

We will need less farmland if we eat less meat because we’ll eliminate large losses of calories. A natural, forested environment would be restored on billions of hectares by doing this.

Isn’t it time to shift to a completely plant-based meals to save your health and your environment? If you can’t cook, then consider a  healthy tiffin service in Bangalore!

Source: Our World in Data