Why Going Vegan Could Help Save the Planet

Why Going Vegan Could Help Save the Planet

Image caption: Author Dan Gay, with partner Lucy Newman and rescued cow Anya at Catskill Animal Sanctuary (CAS). Anya was a dairy cow, but being a twin, is unlikely to ever produce milk. Her owner was planning to have her killed immediately but was convinced to surrender her to CAS instead.

By: Dan Gay

What would you say if you met someone who, for every meal they ate, also purchased or cooked an additional five equivalent plates, and then threw those five meals directly into the trash? Probably, you would think this was shockingly wasteful, especially since this is happening every day, three times a day. If you’re concerned about the environment, this would be especially infuriating, because this kind of clear waste is a large part of why the globe is experiencing so much climate change and other environmental issues.

And what if nearly everyone was doing this three times a day, every single day?

The shocking reality is, although no one is intentionally acting like this, by eating meat and other animal products, the result is nearly the same. The reason is that animals need to eat  in order to grow, and they’re usually given grains, corn, and/or soy. Every pound of edible flesh that you end up with requires at least five pounds of feed (Feed-to-Meat – Conversion Inefficiency Ratios, 2015). And that’s for chicken, the most efficient animal calorie converter. For pigs, it takes about nine pounds of feed to get one pound of meat, and for cows, it takes a whopping 25 pounds of feed to get one pound of beef. Grass-fed cows are not the answer either, because that accounts for only 1% of beef in the United States due to their higher water, land, and time requirements, and they actually produce more methane anyways (due to a longer growing period before slaughter). (Hayek & Garrett, 2018).

Greenhouse gas emissions per 1kg of food (University of Victoria, 2023).

In the above chart, you can see the greenhouse gas emissions of several common foods. Notice that the top 10 are all animal products, and even the least bad of those, eggs, has almost double the carbon impact of the highest plant food, grains. Also, note that the above form of waste is in addition to what we normally think of as food waste, which is around 30% of all food – food that is spoiled, past expiration, defective or uneaten.

If you’re like most people, the idea of food being a major cause of climate change likely comes as a surprise. After all, most environmentalist organizations are focused on the impact of power usage and transportation that uses fossil fuels. Together, these are the biggest slices of the pie, but that doesn’t mean we should ignore the impact of food, as this is something we as consumers have control over and requires as little effort as purchasing different options at the grocery store. According to Joseph Poore, and Environmental Science researchers at the University of Oxford, “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.”

In fact, according to research, agriculture accounts for an estimated 20-26% of greenhouse gas emissions (Ritchie, Rosado, & Roser, 2022). Not only that, but it accounts for 40% of the world’s methane emissions. According to the Global Warming Potential over 20 years (GWP20) estimate, which weighs methane by three times more than before (because methane can dissipate within 20 years in the atmosphere, and the next 20 years are the most critical for avoiding climate disaster), methane accounts for one third of global warming emissions. This means that agriculture methane emissions alone account for 40% of one third, or 13%, of the global warming problem.

That’s a huge amount of emissions that could be eliminated if those living in developed countries simply changed what they ate. Additionally, not only would total emissions go down, but requiring less crop and grazing land to support cattle means more land that could be rewilded, and the replanting of indigenous trees and other foliage would be enough to move the needle on global warming on its own. Certainly, people need to eat, but if we can reduce the carbon footprint of our food from about 25% of the world’s emissions to approximately 8%, reduce methane emissions by 40%, and replant thousands of acres of trees, that is a significant impact worth talking about.

The environmental impacts of food and agriculture (Ritchie, Rosado, & Roser, 2022).

How could this be done? According to a recent peer-reviewed study at the University of Oxford, a plant-based diet accounts for 75% less greenhouse gas emissions than the diet of someone who consumes more than 3.5 ounces of meat a day (Scarborough, 2023). The above chart shows a total of 52.4 billion tons of CO2e, but that comes from 2018 data (the chart is still useful as the relative percentages of emission sources is about the same today), so we will use the 2022 number of 59 gigatons (Rothenberg, 2023). If the 26% of the 59 gigatons of CO2e global emissions come from animal agriculture, that gives us roughly 15.3 gigatons of CO2e. Multiply that by one quarter, and we have 3.8 gigatons. That means our new total percentage of emissions due to agriculture would be 3.8/47.5 (the 47.5 gigatons comes from 59-(15.3-3.8)=47.5), which comes out to 8.0%. In summary, this means that if the global population shifted to a plant-based diet, CO2 emissions would be down a massive 18 percent! That’s more than all emission due to transportation (cars, trains, planes, etc), which account for 16.2% of global emissions (Ritchie, 2020).

Of course, this change would never happen overnight. That doesn’t mean it shouldn’t be pursued at all, however. In fact, no meaningful positive change for the environment will happen overnight, and certainly not the global shift to electric vehicles and a solar/wind powered electric grid. To best protect our world, the environment, and our future, all of these reductions in emissions should be pursued in tandem and with great vigor.

Not convinced that an 18% decrease in global greenhouse gas emissions is enough of an incentive to change your diet? Well, you’re not alone. After all, 80% of the world’s population has been eating meat, dairy, and eggs their entire lives. It’s a deeply ingrained and accepted aspect of society. But should it stay that way?

You may have noticed that so far this article has often referred to a plant-based diet, but it has not used the words: vegan diet. Don’t these mean the same thing? What is a vegan, anyways? According to the Vegan Society:

            “Veganism is a philosophy and way of living which seeks to exclude—as far as is possible and practicable—all forms of exploitation of, and cruelty to, animals for food, clothing or any other purpose…” (Definition of Veganism, 1988).

This means that someone who is vegan has not just made a diet change, but also follows an ethical principle to avoid the exploitation of animals. This means a vegan would also not buy or wear leather, purchase a dog from a breeder (adopt don’t shop!), or visit/support a zoo. Your initial reaction might be that this sounds preachy and annoying, but bear with me for a moment.

If you’ve made it this far in this article, odds are that you are an individual who cares about and is motivated to prevent climate disaster and protect our environment. Still, you may be wondering: “Why should I change my lifestyle so dramatically for a cause that only accounts for 18% of global carbon emissions?” That’s a good question, but first it is worth asking yourself why you are so motivated about protecting the environment to begin with.

Perhaps you are motivated by empathy when you hear the tragic mating call of the last Kaua’I ‘o’o bird, a species that, like over 880 other animals species (that we know of), is now extinct due to humans. Perhaps you are motivated by the fact that over 1 million plant and animal species are threatened with extinction within the next few decades (United Nations, 2019). Perhaps you are motivated by rainforest deforestation (Cattle ranching is responsible for 80% of rainforest deforestation across all Amazon countries (Amazon Aid, 2022)). Or perhaps you are simply motivated by a desire to not see humanity itself go extinct itself.

Cattle ranching in the Amazon Rainforest (McCoy & Ledur, 2022); image licensed from AP.

If any of those other reasons apply to you, then it’s very likely that animal cruelty is also against your principles. Even the last reason; because animal rights are linked to human rights. We currently grow enough food to feed 10-12 billion people, and yet 800 million people are starving (remember the inefficiencies of raising livestock) (Pimentel, n.d.); animal agriculture companies have often violated human rights, often to the extreme of slavery – forcing people to live on a fishing boat or work in slaughter houses (Lee, 2010) ( Human Rights Watch, 2018); slaughterhouse workers (who are often disadvantaged minorities) have some of the highest rates of injury and post-traumatic stress disorder in any profession (Winders & Abrell, 2021); Brazil’s indigenous tribes have been displaced and even hunted by cattle ranchers (Baines, 2013); in countries like Bangladesh, over 95% of people who work in tanneries die before the age of 50 due to exposure to toxic chemicals (Boseley, 2017); and, overuse of antibiotics in animal agriculture is contributing to the emergence of antibiotic resistant diseases (World Health Organization, 2017) that could cause up to 10 million deaths annually by 2050 (Anderson, 2023).

Ultimately, all these reasons combined are why everyone – especially those motivated to help fight climate disaster – should consider veganism. In terms of carbon emissions, cutting meat out of your diet, specifically red meat, would get you 50% of the emissions reduction that a meat eater could conceivably achieve through diet change (Buckely, 2023). However, that still leaves half – roughly 10 pounds of CO2 a day – that can be reduced. Not to mention the other costs mentioned above, or that fact that even the egg and dairy industry are surprisingly cruel. Egg laying hens are a different breed than meat chickens, which means that all male chicks are “worthless,” and killed via suffocation or maceration on the day they are born. For a female cow to produce milk, she (like all mammals) must have recently given birth, and again, all males are “worthless,” and are usually separated from their mothers within two days of birth, and then are either killed immediately or slaughtered a few weeks later for veal (there would be no veal industry without dairy farming). These are standard practices everywhere in the world, including the USA, UK, Australia, and even Sweden, which reportedly has one of the highest animal welfare standards of any country (Martz, 2021). For anyone who disbelieves this or wishes to learn more, and can stomach the truth, I would highly recommend watching the free documentary Dominion. If you cannot stomach watching it, I would ask: why are you putting it in your stomach to begin with?

The number of animals slaughtered for meat every day (Roser, 2023).

I mentioned earlier that people often feel that veganism and vegans come off as preachy or annoying. I understand why this is the case, and I understand why people are resistant to change their behavior so dramatically. Personally, I used to be a huge meat eater – I even got a hunting license not long before I was exposed to this same information – and I never would have thought I’d one day become a vegan animal activist. However, it turned out to be much easier than I thought. If you’re in the United States, for example, switching to a vegan diet mostly entails going to your local grocery store’s plant-based section and loading up on easy replacements like Beyond/Impossible Meat, Gardein, Violife cheese, oat/soy milk, Just Egg, etc. to substitute for the foods you’re used to. Or if you’re in a healthy mood, you can stock up on produce, lentils, tofu, beans, and more. If you want help, check out something like Veganuary or Vegan Easy’s 30 Day Challenge. Give plant-based a try, and you’ll most likely find out how easy a change it really is. Your body will thank you. The animal world will thank you. And your planet will thank you!

If you find the evidence convincing – that a vegan diet could reduce your carbon emissions due to food by 75%, and that animal agriculture is awful for the environment and for the animals – then I urge you to consider a shift to a vegan lifestyle.

For you, it’s a lifestyle, but for the animals, it’s their lives.


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