Vegan Diets: Saving Earth, One Bite At A Time

A vegan diet is a plant-based diet that excludes all animal products, including meat, dairy, eggs, and honey. In recent years, veganism has gained popularity, with a 300% increase in vegans in the UK between 2014 and 2019. Many people adopt a vegan lifestyle for ethical reasons, such as animal welfare and environmental concerns. Research shows that a vegan diet has a significantly lower impact on the Earth's climate than diets that include animal products. This is mainly due to the high environmental cost of industrialised animal farming, which generates large amounts of methane and carbon dioxide, contributing to climate change.

Reduced greenhouse gas emissions

A vegan diet can significantly reduce greenhouse gas emissions. According to the United Nations' Intergovernmental Panel on Climate Change, shifting from meat and animal products to plant-based diets can substantially reduce carbon footprints and mitigate climate change. This is because meat and dairy products fuel the climate crisis.

The production of meat and dairy accounts for a large proportion of greenhouse gas emissions from food production. Beef, in particular, contributes the most to global greenhouse gas emissions. Animal products, in general, require more resources and cause higher emissions than plant-based alternatives.

A report by the United Nations Environment Programme states that reducing livestock herds would also reduce methane emissions, the second-largest contributor to global warming after carbon dioxide. Cattle produce methane as part of their normal digestive process, and when they burp, the methane is released into the atmosphere.

Swapping beef for beans, for example, could help countries reach their targeted greenhouse gas emission reductions. A study found that legume substitution could account for 46-74% of the required reductions. Similarly, another study showed that eating 75 grams of beef daily for a year contributes to greenhouse gas emissions equivalent to driving a car 7,196 miles, while eating 150 grams of beans daily for a year is equivalent to driving a car 93 miles.

By switching to a vegan diet, it is projected that food-related emissions could drop by 68% within 15 years, helping to limit global warming. This is supported by a report in The Lancet, which concluded that a shift towards plant-based foods is vital for promoting the health of our planet.

Less water usage

Agriculture is the world's largest water-consuming sector, accounting for about 70% of freshwater use. Meat and dairy products are the leaders in agricultural water use.

It takes 1,800 gallons of water to produce just one pound of beef. That's the equivalent of about 100 showers for the average American. If the US cut its consumption of animal products in half, food production would require 37% less water.

Producing a glass of almond milk requires 74 litres of water, which is more than a typical shower. Rice milk is also water-intensive, requiring 54 litres of water per glass. However, these numbers are still lower than those for dairy milk. Soya and oat milk are more water-efficient alternatives.

Avocados are another water-intensive crop. While it is difficult to determine the exact amount, some sources suggest that it takes 227 litres of water to grow a single avocado, while others put the figure at 824 litres per kilogram.

A global shift to a plant-based diet could reduce greenhouse gases caused by food production by 70% by 2050. Shifting subsidies from animal products to plant-based foods meant for human consumption could help fight climate change and improve public health.

Lower agricultural land use

The adoption of a vegan diet would significantly reduce global agricultural land use. Research suggests that a shift to a plant-based diet would decrease land use by 75%, from 4.1 billion hectares to 1 billion hectares. This reduction is mainly due to the lower land requirements of plant-based foods compared to animal-based products.

Firstly, plant-based diets require less grazing land. Livestock farming, particularly for beef and lamb, is highly land-intensive. It takes around 100 times more land to produce a kilocalorie of beef or lamb than plant-based alternatives. This is because large areas of pasture are needed to raise cows and sheep, and two-thirds of these pastures are unsuitable for growing crops. If animal agriculture were abandoned, billions of hectares of land could be left to recover, benefiting biodiversity and carbon sequestration.

Secondly, plant-based diets also require less cropland. Currently, a large proportion of cereals and soy are fed to farmed animals, rather than being consumed directly by humans. Globally, only 48% of cereals are eaten by people, with 41% going to animal feed and 11% used as biofuel. Similarly, only 7% of soy is used for human consumption, with the majority going towards animal feed and oil production. By contrast, crops grown for human consumption, such as beans, peas, and tofu, are more land-efficient and can provide a nutritious diet for the world's population.

The inefficiency of animal agriculture is further highlighted by the energy and protein losses that occur when feeding livestock. For example, beef has an energy efficiency of about 2%, meaning that for every 100 kilocalories fed to a cow, only 2 kilocalories are obtained from eating beef. This is because most of the energy fed to animals is used to keep them alive, rather than being converted into meat, milk, or eggs. In contrast, smaller animals like chickens and fish tend to have a lower environmental impact as they are more efficient at converting feed into edible weight.

In summary, a vegan diet would substantially reduce agricultural land use by decreasing the need for grazing land and making more efficient use of cropland. This would have positive knock-on effects for the environment, including reducing deforestation and biodiversity loss, and allowing natural vegetation and ecosystems to recover.

Alleviated hunger

Animal agriculture uses resources inefficiently. A report by the Physicians Committee for Responsible Medicine found that more than 820 million people globally lack sufficient food and that almost two-thirds of soybeans, maize, and barley, and about a third of all grains are used as animal feed.

The inefficiency of animal agriculture is further highlighted by the fact that agriculture occupies 40% of Earth's ice-free landmass, with animal products having a large environmental footprint on croplands. A 2017 study projected that if Americans consumed more beans and less beef, 42% of cropland could be freed up.

The Lancet report also found that unhealthy diets are the largest global burden of disease, surpassing tobacco use as the leading cause of death and disease worldwide. Eating more plants and fewer animal products could prevent 10.9 to 11.6 million premature deaths from heart disease, diabetes, and other chronic conditions annually.

A global shift to a plant-based diet could reduce mortality and greenhouse gases caused by food production by 10% and 70%, respectively, by 2050. This shift would also help address world hunger by reducing the amount of cropland needed for agriculture and making crops directly available for human consumption rather than being used as animal feed.

In addition to alleviating hunger, a vegan diet has the potential to reduce water scarcity. Agriculture accounts for about 70% of freshwater use, with meat and dairy products leading the way in agricultural water consumption. Producing just one pound of beef requires 1,800 gallons of water, while another study estimated that if the United States cut animal product consumption in half, food production would require 37% less water.

Improved health

A vegan diet can have a wide range of health benefits, from lowering the risk of chronic diseases to supporting weight loss.

Lower Risk of Chronic Diseases

Vegan diets tend to be rich in nutrients and low in saturated fats. Research suggests that the diet can improve heart health, protect against cancer, and lower the risk of type 2 diabetes. A large-scale 2019 study linked a higher intake of plant-based foods and a lower intake of animal foods with a reduced risk of heart disease and death in adults. Plant-based diets have also been linked to a lower risk of stroke, with one study finding that the highest consumers of fruits and vegetables had a 21% lower risk of stroke than those who consumed the least.

Weight Loss

Vegan diets can also aid weight loss. People on a vegan diet tend to have a lower body mass index (BMI) than those following other diets. Many animal foods are high in fat and calories, so replacing them with low-calorie plant-based foods can help with weight management. However, it is important to note that eating lots of processed or high-fat plant-based foods can lead to unhealthy weight gain.

Improved Skin

Dairy consumption has been linked to exacerbating acne in both men and women, so removing this from the diet can help improve skin issues. In addition, vegans typically eat more fruit and vegetables, which provide antioxidants and vitamins that are essential for healthy skin.

Reduced Arthritis Pain

Studies have shown that a diet high in healthy vegan foods can help reduce the symptoms of arthritis, as consuming animal-derived foods is linked to pain-causing inflammation. Eating probiotic plant-based foods such as fermented vegetables and non-dairy yogurts can boost good bacteria in the large intestine, helping to reduce inflammation.

Improved Mood

Some studies have shown that vegans and vegetarians had better scores on depression tests and mood profiles than those who ate meat and fish.

Other Health Benefits

Vegan diets have also been linked to a reduced risk of Alzheimer's and improved kidney function.

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