Today, veganism is frequently proposed as a solution to the health and environmental challenges posed by meat-centric diets. As a personal trainer, I constantly ponder on whether or not the vegan diet is a “healthy” one. At the same time, I am genuinely interested in the connection between personal health and environmental sustainability.
This has left me with two questions. The first is, ‘Are human beings meant to be on an entirely plant-based diet?’ The second is, ‘If we aren’t able to fully thrive as strict vegans, what does this mean for environmentalism?
Our food, our physiology—are people meant to vegans, or are they meant to also eat meat?
Meat has been linked to various illnesses and conditions: from heart disease and cancer, to obesity and gout. Further, adding more plants into any diet has been proven time and again to improve one’s health. Increasing plant-based food intake usually helps people achieve an ideal weight, while boosting their metabolic rate and vitamin profile.
Because of this, many believe that humans are actually physiologically adapted to be mainly, or even exclusively plant eaters. Much of this proposed evidence for evolution-mandated veganism, however, does not hold up well under scrutiny.
Humans are weak and soft, not powerful kings of the jungle. Therefore, they are meant to be vegan.
This school of thought argues that humans are not physically adapted as carnivores. We are slow and weak; we have no real fangs and no claws. Matched up against non-human carnivores of comparable size, we would surely end up being the lunch.
While this position makes sense at first glance, it ignores the adaptations we do have, which in fact make us very powerful hunters. One example of this is our most famous one: our big brains. The cognitive abilities we possess are no less important than fangs or claws. They give us, amongst other things, the ability to devise and create tools like spears, traps, and guns.
These technological advancements do not fall outside of biology. They exist specifically because our biology enables us to produce them, and in turn they make us pretty good hunters.
Another physical adaptation related to our hunting prowess may be our shoulders. The design of human shoulder joints gives us the unique ability to throw with both great velocity and great accuracy. Other primates can throw, but they do so rather poorly.
One hypothesis is that, coupled with our bipedal nature, our shoulders make it possible for us to hurl spears with deadly force and precision. Unlike other carnivores, we can make kills at a distance, with less physical effort, and much less exposure to danger.
Human stomachs are longer than carnivore stomachs and resemble herbivore stomachs more. Therefore, they are meant to process only plant-based foods.
Another often-made argument for veganism as our anthropological default is that human stomachs are different from carnivore stomachs. Ours are longer than carnivore ones, it says, to allow time to digest things like plants. Moreover, the acids in our digestive tracts are not as strong as those of the typical carnivore. According to this hypothesis, this distinction is why we avoid eating bones.
While this stance sounds reasonable, it assumes that our stomach configuration is related only to digestion. Well, another theory about why our guts are designed the way they are involves our brains.
See, brains are metabolically costly. It takes a lot of energy to keep them going. Guts are also energy expensive, especially when digesting. The ‘expensive tissue hypothesis’ posits: as humans developed larger brains, our guts shrank to compensate for the increased energy demand. Meaning, smaller intestines were the tradeoff for having more energy-intensive brains.
From an evolutionary perspective, this tradeoff seems to have come about so that we may be able to procure higher quality foods. Our brains evolved, it seems, to allow us to hunt for meat, or process food with stone tools and fire. While only a hypothesis, this idea introduces reasons for our stomach makeup that go beyond just the digestive process.
Veganism and vitamin B12
In any discussion about veganism or plant-based diets, vitamin B12 simply can’t be ignored. B12 is a critical vitamin without which the human nervous system would cease to function. Severe vitamin B12 deficiency can lead to various debilitating symptoms, including weakness, loss of balance, nerve damage, and vision loss. Not having enough of it in one’s system, in short, is not an option.
The only type of vitamin B12 humans are able to absorb efficiently is the kind that is produced by microorganisms. These bacteria often live in the intestines of animals that eat them, making these animals’ meat the most practical vehicle for obtaining vitamin B12. If humans were designed to eat plant and plant-derived products exclusively, this technicality would seem a large oversight.
What does the need for meat and animal consumption mean for food systems and the environment?
Studying our physiology and behaviour through an evolutionary lens, it seems the human body was designed to survive and reproduce, nothing more. Whatever behaviour facilitates and enhances these two things should therefore be fair game in the natural world. Actions that threaten our environment and resources—both integral factors in our ability to survive and replicate—are thus undesirable.
From my studies and in my experience, it appears consuming animal products intelligently and in moderation protects our species’ survival. The modern large-scale farming model that produces meat and its derivatives, however, seems to harm the very habitat that nurtures and nourishes us as a species. This leads us to ask, ‘Is it possible to have a sustainable food system that involves farming animals?’
We need to reduce our consumption of meat.
“The U.S. is producing way more calories than we need, which partly explains why we have very high levels of food waste and high levels of obesity,” says Dr. Pamela Koch, Executive Director of the Laurie M. Tisch Center for Food, Education, and Policy at Columbia University.
Meat and animal-derived foods are produced today in needlessly large amounts, and at a high environmental and social cost. Americans eat around 270 pounds per person per year of meat alone. This amount is far more than needed to hit optimal protein, B12, or other requirements.
“We’re ruining the planet not because we eat animals, but because we eat such a quantity,” explains Mary Jane Detroyer, a registered dietitian in New York City. “People eat three or four times the amount of protein than they need.”
However, I believe the antidote to excessive intake isn’t necessarily strict veganism, or complete meat abstinence. A viable option for both health and environment may simply be to reduce one’s meat consumption. Doing Meatless Mondays, or cutting weekly meat and animal product servings down by 20 to 30 percent, can spark positive changes to your health, while lowering your environmental impact.
We need to make better dietary choices.
A great way to reject rampant meat overproduction is to vet the quality of your animal produce. Small, local farms often raise animals, but as part of a biodynamic ecosystem, which is one that strives to maintain a diverse, balanced, and sustainable environment.
Meat from biodynamic or organic farms comes at a vastly higher quality than meat sold in bigger markets. They’re usually safe from antibiotic treatments, saline injections, and cruel breeding conditions found in supersized livestock farms.
Following an alternative farm’s production cycle means you’ll get some meat, sometimes. Sourcing from such farms that are local or near your home also means your animal produce will have traveled fewer food miles than have cuts driven or flown in from afar.
We need to take control of what goes on our plates.
Further, a huge contributor to obesity in America is the ease and convenience at which calorie-rich processed and cooked meats are acquired. “If you can go buy your fried chicken, and you don’t have to stand in the kitchen, cut it up, cut the extra fat off, clean it, and then stand there and fry it,” explains Detroyer, “then you’ll be more likely to eat it often.”
Committing to eating only meat that you have prepared and cooked yourself is one way to combat this. When you resolve to only eat what you prepare and cook, you skip the excessive salt and fat that comes with restaurant, deli, or pre-seasoned grocery meats.
What’s more, doing so conditions your brain to understand that eating animal protein takes time and effort to properly enjoy. This decreases the likelihood that you will do it often, thereby trimming down your overall meat consumption.
We need to eat more plants.
Preparing and cooking vegetables can be as convenient as anything else. A quick search on Instagram or YouTube will show you a never-ending stream of delicious, easy-to-follow vegan and plant-based recipes.
“A lot of people aren’t aware of simple things they can eat, like edamame or pre-cooked tofu,” Detroyer says. “Also, many people think they have to go fresh vegetables all the time, when there is good research that shows frozen are just as healthy.”
This article is by no means a definitive statement that vegan should be the dominant eating style of our society. However, we continue to seek a more just and more sustainable feeding culture that advances the wellbeing of both humans and our habitat.
Whether or not this prescriptive diet should be entirely plant-based, or straight-edge veganism, to me remains unclear. What’s clear is that we must eat less meat, and that we must always be conscious of our meat’s origin and quality, before purchasing, preparing, and partaking of it.
Title image courtesy of Rustic Vegan via Unsplash
1. Lieberman, D. (2014). The story of the human body: evolution, health, and disease. New York: Vintage Books.
2. Comparative Support for the Expensive Tissue Hypothesis – https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4312921/
3. The Body’s Vitamin B-12 Store – http://www.b12-vitamin.com/body-store/
4. A Nation Of Meat Eaters – https://www.npr.org/sections/thesalt/2012/06/27/155527365/visualizing-a-nation-of-meat-eaters
5. Vitamin B-12 From Algae Appears Not To Be Bioavaliable – https://www.ncbi.nlm.nih.gov/pubmed/2000824
6. Vegan Diet, Subnormal Vitamin B-12 Status and Cardiovascular Health – https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4145307/
7. Imhoff, Daniel. (2011). Food Fight: The Citizen’s Guide to the Next Food and Farm Bill. Healdsburg CA :Watershed Media