The Environmental Impacts Of Animal Agriculture
Updated: May 5, 2021
You’ll often hear people advocating for a reduction in animal product consumption for ethical reasons, but did you know that animal agriculture also has a massive environmental impact? Its contribution to climate change, deforestation, air and water pollution and other concerns have been increasingly coming to light as more of us become aware of our ecological impact.
If you want to learn more about the environmental footprint of your diet – and how you can reduce it by avoiding animal products – we’ve created this simple comprehensive guide to the environmental impacts of animal agriculture.
Contributing To Climate Change Food production as a whole is responsible for one-quarter of all greenhouse gas emissions. Many of us work on buying foods that are local and in season – but there’s a much more efficient way of reducing the impact of the food that we eat on the climate.
Animal products are some of the foods with the highest carbon footprint. For example, an analysis of the carbon footprints of the diets of people living within the EU has shown that 83% of an average person’s food-related greenhouse gas emissions come from the production of meat, eggs and dairy. Although animal products are often argued to be an important source of protein, they are the most environmentally damaging sources compared to plant-based options. For example, producing 100 grams of protein from beef releases close to 50kg (over 110 lbs) of CO2 equivalents.
Where is all this pollution coming from? There are four main sources: deforestation, animal and feed farming, processing and transport.
The supply chain for animal products inherently uses more land than that of plant-based foods. This
is because instead of growing plants to be eaten by humans, animal agriculture grows plants to be eaten by animals which are then eaten by humans. The animal acts as an intermediary for nutrients, making the production much less efficient and sustainable as I will demonstrate in the following paragraphs.
Beef, lamb and sheep are the most environmentally-taxing animal products, but other animal products are still more demanding than plant-based options. The land used to house the animals isn’t the only area needed – the land used to grow livestock feed is also crucial. As the overall demand for animal products and food in general grows, more space needs to be made to account for production – this is usually done by clearing out natural areas. Often, the livestock feed is grown in the tropics, where deforestation is most damaging. For example, soy is one common culprit of deforestation – but did you know that almost 80% of all world’s soybean production is fed to livestock? The resulting deforestation brings even more environmental damage, including loss of biodiversity, disruption of water cycles and increasing erosion. Additionally, deforestation releases the carbon stored in trees into the atmosphere.
To demonstrate the inefficiency of growing animals for food I'd like to put the feed conversion rates into perspective. For every seven pounds of corn fed to a cow, she will gain 1 pound. There are 1,656 calories in one pound of corn, meaning there are 11,592 calories in 7 pounds. Conversely, there are only 798 calories in one pound of beef. That is approximately 14 times more calories if ingesting the grain directly. If that corn were given to people (considering a 2,000 calorie per day diet), you could feed a little under 6 people, or 5.7 people for the entire day. Or if given to the cow and then eating the cow you could feed one meal to one person, not even their entire daily recommended caloric intake.
Fossil fuels used for energy generation and transport. It takes a lot of power to run Concentrated Animal Feeding Operations (CAFOs) and slaughterhouses, most of which still comes from the burning of fossil fuels. Additionally, methane is produced by animals and released from their manure. Cows and sheep produce methane when they digest – a greenhouse gas 80x more potent in the short term than CO2. Aside from the impact of CAFOs by themselves, we also need to consider the impact of producing livestock feed – often, chemical fertilizers are used to maximise yield. These chemicals seep through the soil into groundwater and other water sources leading to pollution and ocean dead zones. Lastly, animal agriculture and Concentrated Animal Feeding Operations in general also largely waste and pollute one of the most precious resources of this planet – water. While some plant-based foods are also very water-intensive, and agriculture in general increasingly pollutes our waters by using chemical fertilizers, pesticides and herbicides, animal products top the charts when we consider their water footprint (mainly fish, seafood and dairy). Again, we need to come back to the inefficiency of animal agriculture – it simply takes significantly higher amounts of water to produce crops to feed to livestock which is then consumed by humans, compared to us consuming the original plants. Aside from watering livestock feed, CAFOs use a lot of water to meet the animal’s minimum daily water needs and to clean their facilities.
With industrial fishing in particular, another water pollution problem arises because of the use of mainly plastic fishing gear, which is frequently discarded into the ocean. In fact, industrial fishing has been found to be the largest marine plastic polluter. Any plastic gear also releases microscopic plastic particles – microplastics – into the water, which are associated with further environmental issues.
As you can see, there is environmental degradation at every stage of animal agriculture. Here, we have only touched the tip of the iceberg.