Planet Arborist

What is the biggest change I can make to lower my carbon foot print? Plant-based food and sustainability

  • April 1, 2020
  • by Tania Gault

The planet won’t be able to sustain us all if we don’t change the way we eat

As the global population grows, so does the demand for food production. By most estimates there will be close to 10 billion people on our planet by 2050. That’s a lot of people! What sustainability means for food production with this number in mind, is that we need to ensure we can feed this expanding population with high-quality nutritious foods. More people means a greater need for calories and nutrition from farmers and food manufacturers. This in turn puts an enormous amount of pressure on the planet to provide enough space, water and plant nutrients to do so, let alone the strain on the climate. Food production uses 70% of freshwater[1], occupies 40% of global land, causes ocean dead zones, and is responsible for our oceans being overfished. Our current production techniques and our eating habits simply won’t work with three billion more people on the planet, so what can we do to lighten our footprint and move in a direction that is both sustainable and healthier for both the planet and ourselves? What is the true impact on the planet from the food on our plate?

The Carbon Footprint of Animal Agriculture is bigger than all transportation combined

Animal agriculture, in all its shapes and sizes, has a huge impact on the environment. It is responsible for 18% of total global greenhouse gas emissions, which is more than the entire transportation sector. That is all cars, trucks, planes, trains, ships and everything in between, all put together! Agriculture in its current form is the driver of global environmental changes, and current global food systems are simply not sustainable. Moving towards a plant-forward diet, which means cutting your consumption of animal products (meat, fish, dairy, eggs and honey), helps to cut total greenhouse gas emissions. As an example, researchers at Oxford University and the Swiss agricultural research institute, Agroscope, found that the average CO2e emissions (CO2e  – e for equivalent – is a metric to describe different greenhouse gases as a common unit) from 100g of protein sourced from beef is 50kg, which dwarfs the emissions of a 100g of protein sourced from beans in comparison which is 0.3kg. This number for beef (from 20kg up to 105kg) does vary depending on the way it was produced, in which region, and with which type of feed is used, but even the lowest-impact beef producers create many times the emissions of an equivalent plant-based protein such as beans[2].

Greenhouse Gases – it’s not all about CO2 – think CO2 equivalent

As highlighted above, is not enough to only consider the “Carbon Footprint” of animal agriculture, as it doesn’t include all of the other greenhouse gases that have a detrimental impact on our environment. Animal agriculture produces large amounts of gases like Nitrogen Oxide and Methane which are also directly responsible for climate heating. In fact, the Methane[3] produced primarily by ruminant digestion (cow burps) has a Global Warming Potential (GWP) 104 times greater than Carbon Dioxide over a 20-year timeframe. So we need to consider the CO2 equivalent, represented as the CO2e, that includes the effects of all these gases as if they were CO2[4].

A plant-based diet has benefits for our health and the health of the planet

The Intergovernmental Panel on Climate Change (IPCC), a U.N. body that assesses the science related to climate change, states that ‘a dietary pattern that is higher in plant-based foods, such as vegetables, fruits, whole grains, legumes, nuts, and seeds, and lower in animal-based foods is more health-promoting and is associated with lesser environmental impact (GHG emissions and energy, land, and water use) than is the current average ‘meat-based’ diet.’[5]. Further, ”A vegan diet is probably the single biggest way to reduce your impact on planet Earth, not just greenhouse gases, but global acidification, eutrophication, land use and water use,” said Oxford’s Joseph Poore “It is far bigger than cutting down on your flights or buying an electric car,” he said, as these only cut greenhouse gas emissions[6]. 

Animal Agriculture uses 30% of the world’s freshwater

Water is a finite resource, we cannot live without water. Conserving water is important for multiple reasons, one being that it reduces the energy used to process and deliver water, as well as preparing for future droughts and preserving the environment. Livestock farming consumes a significant amount of water to produce meat. For example it takes 15,000 litres of water to produce 1kg of beef, compared to 1,200 litres of water required to produce 1 kg of corn[7]. It takes between 600 and 1,000 litres of water to make 1 litre of milk[8]. Compare that to about 50 litres to make a litre of oat milk[9]. Even the “worst” plant-based products from a water standpoint are far far better than their animal equivalents.

Worldwide, animal agriculture is responsible for 20 to 33% of all freshwater usage which makes it the world’s largest water-consuming sector. The average Briton’s daily water footprint is 4,645 litres of water. This footprint not only includes direct consumption but also the water used to produce the food and products consumed. Diet has a significant impact on water footprint. A meat and dairy-based diet consumes about 5,000 litres of virtual water a day[10]. A plant based diet consumes at least 3 times less[11]. While minimising your personal water usage is a great thing to do, the biggest impact you can make is by simply reducing or cutting out animal products from your diet and other consumption.

In addition to consuming a lot of water to produce meat, livestock farming also pollutes water resources through the release of waste into our waterways. A dairy farm of about 2,500 cows produces the same amount of waste as a small city. Beyond freshwater usage and greenhouse gases emissions livestock farming damages the environment by creating dead zones in lakes and coastal areas, soil quality degradation, habitat change, and biodiversity loss.

It’s about humans too, not just animals

Switching to a plant-based diet is not only an environmental and animal welfare issue, it’s also a humanitarian one. Worldwide, more than 40 percent of wheat, soy, rye, oat and corn is produced to feed livestock. To produce 500g of beef for human consumption it takes 10 kg of grain. To bring that to life a bit further, on one acre of land where you could produce 250kg of beef, you’d be able to grow 22,000 kg of tomatoes, 24,000 kg of potatoes or 14,000 kg of carrots. A person on a primarily plant-based diet will consume 200 kg of grain per year. Mathematically speaking, if half of Europe’s population stopped eating meat, there would be enough grain to feed 1.4 billion people… that’s 1.5x the number of people who go hungry every day around the world. By consuming fewer animal products we could redirect the resources, land and crops used for animals to feed more people today and into the future.

So what can you do?

It’s pretty clear that the most profound way that we as individuals can reduce greenhouse gas emissions, conserve natural resources like water and land, and stop contributing to the misallocation of food for the hungry, is by simply changing what is on our plates. Reducing your meat intake dramatically has a tremendous impact on the environment. Reducing other animal products such as dairy and eggs reduces this still further. So how should you go about it?

By eating all the delicious plant foods that are out there! Eat more vegetables, fruits, nuts, seeds, legumes and beans. If you aim lower down on the food chain you’re able to lower your impact on the planet quite dramatically. Even small changes have a massive impact.

If you’re feeling inspired to eat more plant-based meals to reduce your environmental impact there are many ways to get started. You could start by doing Meatless Mondays, or switch a specific product like milk to a vegan alternative (there are dozens of different types you can try!). You could also aim to make one of your three meals a day plant-based, and this way, bit by bit, you’ll learn new recipes and get more comfortable with cooking with plants. You could even sign up for Challenge 22 or Veganuary to try a plant-based diet for 22 days.

Summary :
  • At the current rate of population growth the planet won’t be able to sustain us all if we don’t change the way we eat.
  • Think of the effect of all greenhouse gases combined i.e. CO2e.
  • There are significant health benefits in moving to a diet richer in plant based foods.
  • Agriculture is a huge contributor of CO2e but can improve by rebalancing for plant based diets.
  • A plant-based diet is the single biggest change individuals can make to lower their overall carbon footprint
  • A plant-based diet conserves water and land helping to allocate those natural resources to feed more people.
  • Start slow by making small changes in your day to day life.
  • Eat a diet full of delicious, colourful plant foods, aim lower down the food chain for the greatest impact.