Is a vegan diet sustainable?

The number of people that are converting to a vegan diet has increased dramatically in the past few years alone. Ten years ago, there were an estimated 150,000 vegans in Britain but that number has now risen to at least 542,000. With documentaries such as ‘Cowspiracy’ and ‘What the Health’ increasing people’s awareness of the problems with animal agriculture, this number does not seem all that surprising. With all this media attention, the pros and cons of a plant-based diet are something that we often discuss in the office, with team members following various diets, from the committed carnivores to the strictly vegan. It’s a very complex issue without a clear-cut answer, and whilst we don’t claim to be experts in all the different areas of global agriculture and economics, here’s a snapshot of some of the research we’ve done to help you navigate the different arguments a bit more easily.

The main arguments against animal products in terms of sustainability, are linked to the environment. Certainly, the production of meat and other animal products places a heavy burden on the environment, from crops and water required to feed the animals, to the transport and other processes involved.

It’s a known fact that the farming of animals puts a great deal of strain on water supplies as it takes more than 2400 gallons of water to produce 1 pound of beef. That’s 1066 500ml bottles of water that are needed to produce 4 hamburgers. In comparison, only 244 gallons of water is needed to produce 1 pound of tofu. In terms of dairy, 683 gallons of water are needed to produce 1 gallon of milk. By going vegan, one person can save approximately 219,000 gallons of water a year, which is the same amount of water that would be used in the average daily shower, over a period of 35 years. Not only does animal agriculture put immense pressure on water supplies, it also has a significant impact on climate change. In a paper by Goodland and Anhang, it was revealed that livestock and their by-products account for at least 32,000 million tons of carbon dioxide per year, or 51 percent of all worldwide greenhouse gas emissions. Someone who eats more than 3.5 ounces of meat per day generates the equivalent of 7 kilograms of carbon dioxide emissions a day whereas vegans are responsible for 2.9 kilograms. The greenhouse gas emissions of a meat eater are 102 percent higher than those of vegans. With a global population of 7.5 billion, and this number increasing by the second, these figures are only going to get worse.

Furthermore, a plant-based diet requires less land than both the meat and dairy industry, one third less to be precise. 70% of the grain grown in the U.S. alone is fed to livestock and is the equivalent of being enough to feed 800 million people. In Brazil alone, the equivalent of 5.6 million acres of land is used to grow soya beans for animals in Europe. Worldwide, 50% of the grains are being eaten by animals in the industry, while 82% of children living next to livestock are starving. By growing cash crops for animal feed, rather than themselves, this is contributing to malnutrition. It is more efficient and sustainable to use the crops of grains and pulses to feed humans rather than feeding them to animals.

On the other hand, considerably lower quantities of crops and water are required to sustain a vegan diet.

So, if all these facts are true, what would be the problem of everyone turning vegan? Well for starters, in low and middle income economies, livestock accounts for 40-60% of agricultural GDP and farm animals provide livelihoods for almost one billion people. Furthermore, in developing countries, livestock is needed to provide energy-dense, micronutrient-rich food for malnourished children. If everyone were to turn vegan, land would be wasted that could be used to feed other people. This is because different kinds of land are needed to produce different types of food. Grazing land is often unsustainable for growing crops and when parts of the Sahel (south of the Sahara Desert in Africa) were converted from livestock to croplands, the result was desertification, according to BBC reports.

Animal agriculture may be damaging to the environment, but turning vegan can also have significant impacts. The increased demand for avocados, for example, has had a weighty effect on water consumption. Farmers in Mexico have found it more profitable to grow avocados than most other crops. Avocado plantation needs repeated cycles of chemical inputs and puts pressure on local water reserves. It takes an estimated 272 litres of water to produce 2-3 medium sized avocados. Furthermore, food transportation is quickly becoming one of the world’s fastest growing sources of greenhouse gas emissions due to the increase in transporting.

Given both sides of the argument, where does this leave us? The important thing to take from this is to remember every action has an impact on the environment, so we need to be conscious consumers and question wether the food we are buying is having a positive or negative effect on the planet. All things considered, we believe that a good middle ground is focusing on reducing the quantity of animal products we eat. Cutting down consumption of these products will lead to a decrease in the strain on the environment. If every American reduced their meat consumption by just 10% for one year, enough grains would be alleviated from the factory farming industry to have the potential to feed 60 million starving people. Ultimately, we believe it's our mission to encourage people to think more about their choices as consumers and to really value their food. So if you are a committed carnivore, consider trying to curb your meat intake, introducing a #MeatFreeMonday or another easy way to enjoy veggie dishes. And if you are vegetarian or vegan, do some research into the kinds of foods you're eating and ensure that the food you're buying isn't putting an adverse strain on the environment.