Does going vegan actually reduce carbon emissions?

In an era defined by growing environmental concerns, the impact of our dietary choices on the planet has come under increasing scrutiny. Among the various lifestyle changes proposed to combat climate change, adopting a vegan diet is frequently highlighted as a powerful individual action. But how significant is this impact, and what does the evidence truly say about the link between veganism and reduced carbon emissions? This page delves into the science behind these claims, exploring the mechanisms through which a plant-based diet contributes to a lower environmental footprint and addressing common questions about its effectiveness.

The short answer

Yes, going vegan significantly reduces an individual's carbon emissions. Research consistently shows that plant-based diets have a considerably lower environmental footprint than diets that include animal products, primarily due to differences in land use, water consumption, and greenhouse gas emissions associated with their production.

The evidence

The environmental benefits of a vegan diet are well-documented by numerous scientific studies and international bodies. Livestock farming, particularly for beef and dairy, is a major driver of greenhouse gas emissions. These emissions come from various sources, including methane from animal digestion, nitrous oxide from manure and fertilisers, and carbon dioxide from land-use change (e.g., deforestation for pastures or feed crops).

According to a comprehensive study by Joseph Poore and Thomas Nemecek (2018), published in Science, avoiding meat and dairy is the single biggest way to reduce your environmental impact on the planet. Their meta-analysis, which examined data from nearly 40,000 farms across 119 countries, found that food production accounts for a quarter of all human-caused greenhouse gas emissions. Within this, animal products are disproportionately impactful.

Greenhouse gas emissions by food type

The disparity in emissions between different food types is stark. For example, producing 100g of protein from beef generates 25 kg CO2eq, while producing the same amount of protein from peas generates just 0.4 kg CO2eq. This pattern holds true across most animal products when compared to their plant-based alternatives.

Source: Poore & Nemecek, 2018 (data rounded for clarity)

Beyond direct emissions, animal agriculture also consumes vast amounts of land and water. Livestock farming uses around 77% of global agricultural land, yet provides only 18% of the world's calories and 37% of its protein. This inefficient use of resources often leads to deforestation, biodiversity loss, and water pollution.

A 2021 report from the IPCC (Intergovernmental Panel on Climate Change) reiterated the importance of dietary changes, noting that 'sustainable diets and healthy diets are intertwined with low environmental impacts.' They highlight that diets with a higher share of plant-based foods, such as vegetarian or vegan diets, are associated with substantially lower greenhouse gas emissions than diets rich in meat and dairy.

Common counter-arguments

Some argue that the environmental impact of certain plant-based foods, such as avocados or almonds, can be high due to specific farming practices or long-distance transport. While it's true that the carbon footprint of plant-based foods is not zero, and some can be more impactful than others, their average footprint remains significantly lower than animal products.

For example, while almond cultivation is water-intensive in some regions, its overall environmental impact is still considerably less than dairy production. Similarly, air-freighted fruits or vegetables might have a higher footprint than locally grown, seasonal alternatives, but even then, their emissions rarely rival those of meat and dairy products.

Another point often raised is the carbon footprint associated with imported vegan ingredients like soy. However, the vast majority of soy (around 77%) produced globally is used for animal feed, not for human consumption in the form of tofu or soy milk. Therefore, reducing meat consumption indirectly reduces the demand for animal feed crops, which has a much larger land and carbon footprint than direct human consumption of soy.

What this means in practice

Adopting a vegan diet is one of the most effective personal actions an individual can take to reduce their carbon emissions and overall environmental footprint. Even partial shifts, such as reducing meat and dairy intake, can yield significant benefits.

For an individual, moving from an omnivorous diet to a vegan one can cut their food-related carbon footprint by as much as 75%. This impact is greater than reducing car travel or switching to more energy-efficient light bulbs. Beyond carbon, veganism also helps to conserve water, reduce land use, and protect biodiversity.

While personal choices are important, systemic changes are also crucial. Supporting sustainable farming practices, advocating for policy changes that promote plant-based food systems, and educating others about the environmental benefits of dietary shifts are all part of a comprehensive approach to addressing climate change.