The choices we make with our food can be really personal ones. For this reason, we’re not gonna spend time trying to draw really clear right and wrongs about sustainability and food. Instead, we’ll highlight the downsides of both carnivorous and herbivorous diets so that everyone can make well-informed decisions that better suit themselves and their individual lifestyles.

Where did vegan diets come from?

Vegan diets aren’t the new fad they might appear to be! We’ve been eating meat at least since our hunter-gatherer days but plant-based diets have existed for just as long. While the term “vegan” was coined in 1944, religious groups and the like have been opting out of meat since they’ve had the option.

The more recent call for vegan diets from the sustainability realm largely comes from the fact that our livestock contributes heavily to our global emissions. In the United States in 2018, 9.9% of our greenhouse gas emissions came from agriculture. Most of these emissions are in the form of carbon dioxide, nitrous oxide, methane, and ammonia. The livestock industry is also responsible for an incredible amount of waste. In the United States, the industry produces 116,000 pounds of waste per second. Meat and dairy aren’t totally negative, though. As food sources, they offer us proteins, vitamins, and minerals that can be challenging to find elsewhere.

There’s also the problem of space

Livestock contributes to greenhouse gas emissions and that’s troublesome, but we’re also butting up against issues of where to put all of these animals. Across the globe, the 1.4 billion cattle, pigs, and chickens take up 2 billion hectares of grassland (about 1/3 of the world’s total land). Of that 2 billion, 700 million hectares could potentially be used to grow crops that humans can eat directly. This is especially noteworthy because 40% of the harvested crops in the world are used to feed our animals!

Over the last few decades, we’ve seen a massive increase in the amount of meat that we consume so the total area we need for livestock makes sense! With how much we’ve increased our consumption, the livestock industry has actually become the leading cause of clearing forests worldwide.

How much more meat are we eating?

In low and middle-income countries, the demand for meat and dairy has tripled over the last 30 years. An average American consumes over 200 pounds of meat every year! These numbers are even expected to rise. By 2030, our meat consumption is forecasted to rise by another 80%.

The Vegan Side

As mentioned, there are some downsides to veganism as well, though they may seem small in comparison.

We often use fertilizers to grow our produce. Our fertilizers can contribute to greenhouse gas emissions as well. This is mainly the case with artificial fertilizers because we create greenhouse gas emissions both in the production of the actual fertilizers as well as in their use out on the field. Globally, artificial fertilizers contribute at least 3% of greenhouse gas emissions. Common agricultural practice, like tilling, also releases greenhouse gases and helps to speed up the erosion process.

The Most Problematic Vegan Staples

Avocados are huge within the plant-based and non-plant-based communities. Their natural fats and creamy textures are sought after again and again but what some people don’t know is that they take a lot of water to produce. One single mature tree in California will need up to 46 gallons of water every single day in the summer. This is more water than it would take to fill a big bathtub. In some places, like Chile or Peru, we’ve created such a massive demand for avocados that people have begun to illegally extract water. This extraction has been partially blamed for increasing the already existing water-shortage crisis. This seems fitting with the knowledge that a single avocado can require up to 60 gallons of water. The rapid ripening that occurs with avocados means that the fruit gets to the United States and Europe primarily by air travel (one of the most prominent industries in greenhouse gas emissions).

Mushrooms are often used as a meat substitute but they actually also contribute notable greenhouse gas emissions. The mushrooms that we most often buy from our grocery stores (Portobello, button mushrooms, etc.) emit about 3 kg of carbon dioxide. These emissions, however, mostly come from keeping the rooms where the mushrooms grow at the acceptable temperature. Mushrooms emit much less than beef and chicken but they’re on par with saltwater fish and actually emit more than tuna! There is some hope with mushrooms if we’re able to create sustainable compost substitutes for mushrooms to grow in. BBC delves into some of these methods and you can check it out here!

Another great meat substitute is mycoprotein, which is also grown from fungi. You’ll find mycoprotein used in some vegetarian and vegan meat replicas (Quorn being an example!). One of the biggest benefits to mycoprotein is that we only have to use a sliver of land compared to what livestock requires. While mycoprotein does emit some carbon dioxide, more than half of the emissions are caused by the processing and this varies by producers – some producers mix the mycoprotein with egg whites and some use materials that required fertilizers.

Lastly, tree nuts are incredibly important for a lot of vegans. This is primarily because nuts offer a quick avenue for protein and they also provide really unique avenues for dairy substitutes (almond milk, cashew sour cream, etc.). Similar to avocados, tree nuts (cashews, almonds, and walnuts) often require a lot of water. They’re the most water-intensive, large-scale crop globally. Almonds require the most water, pesticide, and fertilizer compared to cashews and walnuts so their environmental impact is disproportionately high. There was a study conducted by the Almond Board of California that found that the average United State’s almond requires 12 liters of water.

So that was a lot of information

It can be such a challenge to pick food that is right for you while also working to be sustainable or zero-waste. There are benefits to livestock that might outweigh the cost of emissions for you personally. For instance, livestock play a vital role in our ecosystems – a role that we would potentially lose out on if we all converted to veganism! Livestock also assists us with food security because these animals will eat the food that we don’t eat, like grass. Livestock helps us with land conservation – because these animals have to have a place to live, roam, and eat! Farmers are currently working to create more productive animals, with more information available here.

Whether you’re interested in giving up meat forever, temporarily, sporadically, or never at all, there are some helpful things you can do to make sure your choices are having the least adverse effect possible. A helpful tool is to buy local! When we buy local, we mitigate the need for transportation emissions and while assisting our local economies. It’s really useful to buy produce that is in season. This can be an incredible challenge because we’ve created a system where we have so much available due to worldwide shipping methods – like when you can find lemons in December! If you’re not in a location where shopping local is super feasible, do your best! For produce, a helpful resource might be Misfits Market – an organic produce delivery service that ships in-season produce to you.

For some local options, check out Community Supported Agriculture (CSA). Nourish Knoxville put together a CSA guide in recent years. You can find that here. To find out more about Community Supported Agriculture and to figure out if it’s the right fit for you, here is a list of pros and cons! For information on local farmer’s markets, where you can find local meat and produce options, check out Nourish Knoxville’s list of East Tennessee markets!

Nourish Knoxville’s list of East TN Farmer’s Markets

Sustainability + Food