How does a vegetarian diet help the environment?

Whereas meat consumption, in certain societies, was or remains a luxury indulged in from time to time, many diets - especially Western diets - now include meat or meat by-products in every meal. We fail to take into account the implications of this cultural norm on the environment. Fortunately, a mindset shift can help reframe the role that meat consumption plays in our environmental footprint. 

How much of global carbon emissions come from food?

It is estimated that between 25 percent to 34 percent of global GHG emissions are caused by food production, taking into account production methods, animal waste, transportation and packaging, among other factors. Food production generates 13.6 billion tonnes of carbon emissions annually - and this number could grow dramatically depending on world population and diets.

Although many suspect that transportation would be the biggest contributor to these emissions, it only accounts for six percent of food production emissions. This means that buying meat from local suppliers does not change the carbon emissions by much. A much greater culprit is land use change (when land, like forests or shorelines, are transformed for food production), which generates 14 percent of food emissions. And even greater yet is meat production.

Why does meat have high greenhouse gas emissions?

Livestock farming (which includes meat, eggs, dairy and fish) accounts for almost one third of all food production emissions, generating over 4.21 billion tonnes of carbon dioxide equivalents annually. Most of livestock’s environmental footprint comes from animal waste and GHG emissions. Cattle produce large amounts of methane gas during digestion due to a process called enteric fermentation. Methane gas is a potent GHG, 80 percent more potent than CO2 in the short run, which is why beef is by far the most harmful food for the environment. Animal waste management and pasture management also cause livestock farming’s emissions to skyrocket.

Notably, changes in land use for livestock farming are hugely disruptive for the environment, accounting for 16 percent of GHG emission and destroying ecosystems, including rainforests and mangrove communities, which are important carbon sinks. When these vital ecosystems are destroyed, so is the potential they had for absorbing climate-changing carbon dioxide from the atmosphere. 

What is the carbon footprint of vegetables and crops?

Frankly stated, all plant-based protein sources have a lower average carbon-emission than animal sources. All crops grown for human consumption account for about 21 percent of the total emissions generated for food production. Looking at this microscopically, however, the difference is enormous: 100 grams of protein from tofu generates 1.6 kilograms of GHG emissions, whereas 100 grams of protein from beef generates 25 kilograms - almost 16 times more. 

The most carbon intensive crops are coffee and chocolate, mostly due to the land-use change that occurs to create farms. While soy farms are also culprits of land-use change, the majority of soy is not used to make tofu, but to make feed for animals on meat farms. 

A lot of energy and resources go into raising livestock for human consumption, from making pastures for them to the energy from plants that they require to grow, and most of this energy is lost before it gets to the human consumer. Animals are much less efficient ways of generating and consuming energy than plants, nuts or seeds.

Here are 7 foods with high carbon footprints

What percentage of a person’s footprint comes from diet? 

Many factors go into an individual’s total carbon footprint, from at-home energy use, travel, transportation and consumer good purchases. Food accounts for one-third of an individual’s carbon emissions, coming especially from meat and dairy consumption. Of course, this depends largely on the individual’s diet and budget. Europeans eat, on average, 1.5 kilograms of meat per week - twice the global average. By comparison, the average Ethiopian eats 7 kilograms of meat per year, generating a much lower carbon footprint.

How much can vegetarianism reduce our carbon footprint?

Changing from a meat-loving diet to vegetarianism can decrease one’s carbon footprint from diet by over 50 percent, depending on the change. That’s the equivalent of driving 1,300 miles less per year. To take the example from above: eating 100 grams of protein from tofu rather than beef would reduce your carbon emissions by 16 times!

In the average European diet, meat, eggs and dairy account for 83 percent of a European’s GHG emissions from diet. Switching to a vegetarian diet can therefore drastically reduce the impact on the environment. Moreover, the effect is compound: as the demand for meat decreases, the incentive to deforest lands and change them for livestock farming becomes less appealing, which could result in higher carbon absorption from the atmosphere by undisturbed forests.

Is complete vegetarianism the only way?

For many cultural, economic, religious and health-related reasons, not everyone is able to switch to a vegetarian diet. Furthermore, it's understandable that many find the complete abstinence from meat challenging. Fortunately, reducing meat intake by even two days a week could be have a positive impact on the environment. Alternating to plant-sourced proteins two days a week could reduce one's carbon footprint from diet by almost 25 percent.

Climate experts have warned that to avoid the consequences of catastrophic global warming, we must reduce GHG emissions to prevent 1.5 degree warming.  One way to achieve this objective is to choose reduce the emissions that come from our diets - especially from highly pollutive diets in the  Global North. While some facets of life are more difficult and costly to change, such as energy consumption or transportation, diet is fortunately a very flexible aspect of our lives that we can creatively modify. 

Image by Dan Cristian Pădureț