Thoughts on the Environmental Effects of Carnivory and Veganism
By Monica @ 5:24 PM   
The popular press is awash with stories these days of how meat contributes to global warming and how many people are turning to veganism to reduce their "carbon footprint". There is even a proposed EPA tax on emissions from farm animals. From Scientific American articles, change.org pieces, and statements like this from respected nutritionists: "The more rice, corn, potatoes, sweet potatoes, and beans you eat, the trimmer and healthier you will be – and with those same food choices you will help save the Planet Earth too", environmentalists, vegans, and animal rights activists are attacking any and all methods of raising animals -- whether for meat, dairy, or any other use -- as contributing to "climate change." But is it true?
Before I deal with actual truth or falsehood of such statements, I'd like to state my position on "climate change" so that I can be as transparent as possible here. First, I do believe the globe is probably warming, and that it might be happening at least partly from human activities. I honestly don't know. However, I don't believe that this in any way justifies the political "solutions" being proposed to "climate change" (cap and trade, coercive laws, etc.). I haven't actually investigated the global warming issue seriously from a scientific standpoint and don't really have time to do so right now. I used to be a dyed in the wool member of the global warming camp and have gone back and forth on the issue over the past, but the fact is that wherever the truth lies, my knowing it would make very little difference in my day to day activities, and thus, it ranks pretty low on my list of self-education priorities. If that disqualifies me in your mind from commenting on the issue of carnivory vs. veganism as it relates to "climate change", so be it. I believe peoples' actual arguments, and whether they are logical or not, are the things that we should be dealing with.
Now that we have that out of the way, let's consider the issue.
First, let's be honest. Vegans and vegetarians raise a number of valid points when it comes to meat production. Some of these are actual problems and some may not be problems but the facts remain: feedlots often contribute to waterway pollution, cattle release methane, and that the way in which the animals are raised (indoors, confined, unsanitary conditions, fed antibiotics as a routine measure because of the immense crowding and wrong food which both foster illness) is, by and large, inhumane. I've blogged on each of these points before, including the absurdity and wastefulness of subsidizing this inefficient method of raising animals through the EQIP program.
Further, it is absolutely true that as we increase in each level of the food chain from primary producer (plants, algae) to primary consumers eating primary producers, to secondary consumers (animals that eat primary consumers), to tertiary consumers (this last category are the top predators in any ecosystem and eat both primary and secondary consumers: wild cats, dogs, humans, eagles, etc. are examples) about 90% of the energy ingested as food is lost as heat and only 10% is converted to biomass. There are some variations in those numbers, but those are the basics: lots of energy lost as heat or waste products as you go up in the food chain/food web. This all makes perfect sense from the standpoint of physics and basic physiology/metabolism. It's so well-documented in the literature that I see no reason to provide references. No one disputes that most of the energy from the fuel in the internal combustion engine is lost as heat rather than converted into mechanical power. It's the same principle in living organisms.
This is the reason that in any given ecosystem, there's an immense amount of biomass of primary producers and hardly any biomass, comparatively speaking, of tertiary consumers, i.e. top predators. This is also the basis for claiming that meat contributes to global warming. After all, if you are running grass or grain through an animal before that animal food gets to a human, lots of the energy is lost as heat or waste. Waste products of respiration are CO2 and water (or CO2 and ethanol or lactic acid if you're a fermenter). One of the waste products of the bacteria in ruminants is methane. Of course, we all know that CO2 and methane are the alleged "bad actors" of "climate change." The logic of the vegan argument is that if you bypass eating the ruminants (or any other animal, for that matter) you are more efficient at converting the calories of primary production (plants) into biomass and you avoid the energy "wastage" and extra CO2 and methane production.
But there are just a few problems with this very simplistic line of argumentation. Let's address them.
First, the assertion that humans evolved as vegetarians, or that their most recent common ancestor was vegetarian, has been blown out of the water. Personally, I think a good vegan diet with proper supplementation and avoidance of processed food is probably head and shoulders about even the standard American diet. But that's not the point. The point is, should people have the right to eat the diet they are designed evolutionarily to eat, the diet that is in their own best interest? Or should they eat a vegan diet to "save the planet", in the words of Dr. McDougall? It's a valid question. If you believe a vegan diet is optimal, that's fine for you, but there are serious issues with the scientific basis of such an argument from an evolutionary and nutritional standpoint. And certainly such a diet shouldn't be foisted on humans everywhere for political reasons if the point of morality is to teach us how to enjoy life to its fullest (as opposed to sacrificing for someone or something else, ultimately suffering or dying sooner than necessary).
Let's take the issue of energy loss. Yes, it's true that lots of food energy is lost as heat when we eat animals. However, there are more subtle points to consider. How does the caloric intake differ between vegans and carnivores or even vegans and meat-heavy omnivores? If Good Calories, Bad Calories is any indication, those with carb-heavy (read: plant-heavy) diets are driven to ingest more calories. I've certainly found this to be true in my own experience. A meat-heavy diet, at least as far as my own personal experience, results in spontaneously reduced caloric intake of as much as 800 calories daily. That's something that is never accounted for in the "carbon footprint" calculations. And honestly, what quantity of greenhouse gases are produced by grain- and legume-fed vegetarians? Beans, beans, the musical fruit, the more you eat the more you toot. Seriously, eating high-carb plant foods causes the production of more intestinal gas. I'm not sure what the chemical composition of that gas is, but the presence of the gas is something everyone who has switched from a high carb to a low carb diet, or spends a lot of time around bean-eating vegetarians, can amply attest to.
Moving on. Is most of the world's land arable and suitable for crop production? It is not. I've blogged about that before. In fact, this is considered a major problem of plant biotechnologists who develop breeding programs to develop crops for less than optimal conditions. Lots of the earth's land, however, is rangeland and quite suitable for animal production.
Another problem is the simplistic assumption about modern-day vs. ancient production of CO2 and methane from cattle. Actually, I'm not even sure the vegan "climate change" activists or their followers want to consider this. There are currently about 100 million head of cattle in the United States. Most of our cattle are grain-fed for at least part of their lives and grain-fed cattle produce about twice as much methane as grass-fed cows. However, they are not grain-fed their entire lives. My best estimate is that at any given point, around 25 million head are being fed this way. Estimates of the number of bison present in pre-settlement times is also as high as 100 million head, with bison being about twice as big as cows. I'm sure many people find it difficult to believe that the American continent could foster twice as much ruminant biomass as it currently does, but the fact is that the Americans plains soil was extremely fertile before modern grain- and soy-based agriculture washed much of it into the ocean, with enormous amounts of primary production (much of it underground in the form of prairie grass). I'm not sure how many head of bison were turned over yearly to predation or hunting. Today, approximately 1/4 of the national herd of cattle makes its way into the food chain yearly. But assuming that grass-fed bison produce similar amounts of methane to grass-fed cows, and that there could have been twice as much bison biomass as current cattle biomass, that means there were probably very similar amounts of methane being produced all along and that this hasn't changed much historically. This pretty much blows away the argument that we should consider cattle per se a significant problem when it comes to global warming.
Finally, let's consider the darling of the environmentalist/vegan movement: soy.
Let's be fair -- soy is a nitrogen fixing plant, meaning it can pull useless nitrogen gas from the air and turn it to valuable, fertilizing ammonia with the aid of bacterial endosymbionts in the root tissue. Even Thomas Jefferson recognized the value of using legume crops such as vetch to restore fertility to depleted soil. Still, soy is a plant with a shallow root system that results in soil erosion when grown in monoculture. Soy is often shipped up from South America, grown on land where rainforests once grew. Then, if the pure soybeans aren't eaten, and they usually aren't, they are processed in an extruder. Here is a picture of a soy extruder:
Hint: that puppy doesn't work on solar or wind power.
Now let's consider the grain-based diet that the vegans want us to go on. Any crop grown in the US today post-1950s in the era of subsidy-powered commodity agriculture requires vast amounts of ammonia fertilizer input through the Haber process. Animals could provide a much more balanced source of fertilizer, and played an important role in agriculture besides meat production prior to the 1950s. Long-term, there is simply no way to completely amend soil without farm animals if we want optimal plant (and thus, human) nutrition. These are the very animals many vegan activists would like to see eliminated to solve "climate change". Even that is absurd. Let's consider the Haber process, shall we? It is responsible for 1/4 of the world's nitrogen fixation and works by burning nitrogen and hydrogen gas through four rounds of heating to between 300-550 degrees C, to produce NH3.
Hint: the fuel for the Haber process does not come from solar or wind power.
OK, vegan activists for climate change. Please tell me which of the two options you think uses more fossil fuel: 1) The Haber process and the fuel required to transport the products of the Haber process to the fields? Or 2) locally raised animals depositing their dung directly on the fields, with all the necessary nutrients (not just nitrogen), as they did 50 years ago and as they still do on many family farms in the United States?
I hope I have demolished the idea that you have any idea how much carnivory vs. veganism truly contributes to "climate change" or "greenhouse gas" production without doing a lot more in-depth calculation in all of the areas mentioned above. Personally, I think my locally raised real bacon is a lot more environmentally friendly than the soy-based Smart Bacon grown with Haber-produced ammonia, shipped to the US, and then processed in an extruder which uses petroleum products. Here are the ingredients in Smart Bacon: Water, soy protein isolate, wheat gluten, soybean oil, textured soy protein concentrate, textured wheat gluten, less than 2% of: natural smoke flavor, natural flavor (from vegetable sources), grill flavor (from sunflower oil), carrageenan, evaporated cane juice, paprika oleoresin (for flavor & color), potassium chloride, sesame oil, spice extractives, fermented rice flour, tapioca dextrin, citric acid, salt. Look at the amount of processing involved. Many of the substances in bold are produced or extracted through an industrial process. How much fossil fuel is used to produce "environmentally friendly" products like Smart Bacon vs. real bacon? Want to bet?
Having fallen prey to "meat is bad for the environment" arguments myself in the past, it disturbs me to see these arguments advance. More and more people are adopting the idea that they will "save the planet" through veganism, often at the expense of their own health. It's fine if their choices stop with them, but ten years ago "cap and trade" would been inconceivable to most people. Today it's being offered up as an actual political "solution", and not a voluntary one. If someone had told me five years ago that the EPA would even consider taxing emissions from farm animals, I'd have laughed in your face.
In light of that, ask yourself whether any of the following is truly an exaggeration:
How long before our animal protein is rationed for the sake of "saving the planet"?
How long after that before vegans, animal rights activists, and environmentalists seriously push to limit or forbid raising livestock in the name of protecting the environment?
And how long after that before we're all forced to be vegan?
In my practical experience, many of the followers of the vegan movement who do so for environmental reasons are, for whatever reason, unable to understand or investigate the science behind the claims for their action. They are simply woefully ignorant. They aren't actually evil people. But the originators of such claims (PETA and others), those who can understand science and who either knowingly start or perpetuate lies for their own ideological ends at the expense of the truth, are hopelessly corrupt.
These lies need to be exposed. More than the simple truth is at stake. For some of us, our very sustenance depends on it.
HT for soy extruder picture: CheeseslaveLabels: Bison, Buffalo, Ethics, Global Warming, Government Idiocy, Grass-fed, Individual Rights, Meat Myths, Pastured, Subsidies
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4 Comments:
While not agreeing with all of your points, for ex, I very much believe in signifigant human contribution to climate change, you have written an excelent argument. I am an ex vegetarian who considers himself an environmentalist. I believe those of us who are out advocating for real food, family farms, and optimal human health are very informed about ecology.I get frustrated when people prescribe veganism as THE solution to everything. Overpopulation is a taboo subject for most but the efficiency argument for not eating meat has this at its base. "if we were all vegan there could be sooo many happily fed humans" You nailed it with pointing out that they dont seem to be concerned with wether or not thiers is an optimal diet.
Further, it is absolutely true that as we increase in each level of the food chain from primary producer (plants, algae) to primary consumers eating primary producers, to secondary consumers (animals that eat primary consumers), to tertiary consumers (this last category are the top predators in any ecosystem and eat both primary and secondary consumers: wild cats, dogs, humans, eagles, etc. are examples) about 90% of the energy ingested as food is lost as heat and only 10% is converted to biomass. There are some variations in those numbers, but those are the basics: lots of energy lost as heat or waste products as you go up in the food chain/food web. This all makes perfect sense from the standpoint of physics and basic physiology/metabolism. It's so well-documented in the literature that I see no reason to provide references. No one disputes that most of the energy from the fuel in the internal combustion engine is lost as heat rather than converted into mechanical power. It's the same principle in living organisms."
I'm sorry about not being able to agree with that latest statement - in a healthy ecosystem things always gets used up in one way or another. Or otherwise it is just not "fuel", providing just energy.
Would you please be able to come up with some kind of scientific backing about this statement of yours, even though you consider it totally unnececessary?
Hi Helm -- I'm not sure exactly where you have a disagreement. Perhaps this clarification will clear it up.
Organisms are inefficient at harvesting the energy from food molecules, while still being more efficient than the internal combustion engine. For instance, about 32% or so of the energy in the chemical bonds of sugars, proteins, and fats is actually harvested in cellular respiration (assuming aerobic respiration) and ultimately converted into chemical energy in the form of ATP. Of course, some of the matter that is ingested is directly or indirectly incorporated into the tissues, and that's a somewhat separate matter -- which I wasn't very clear about. Is that where the misunderstanding lies?
Perhaps you were thinking that I was suggesting that this heat "loss" is a problem. I'm not -- only stating the facts as they are. Both of these things -- both the relative inefficiency of cellular respiration and the fact that most of the ingested material in any organism isn't converted into biomass, are pretty directly observable (particularly the latter. Way more biomass of producers in almost any ecosystem though the numbers vary somewhat). You can check the figures for cellular respiration in any Intro Bio textbook chapter on respiration. You can check the figures for biomass of producers vs. consumers in a basic ecology textbook.
Oh, and my larger point was that although these basic facts are true, and theoretically we *could* support a much larger population of vegetarians than meat eaters on the planet (as warren above suggests) the basic assumptions are too simplistic. The problems, in summary, are:
1) faulty estimates or non-correction for the amount of calories meat-heavy eaters ingest
2) assuming that all land available would be best allocated to crop plant production
3) Incorrect or dishonest assumptions about baseline CO2 or methane production pre-industrialization or at least, what they would currently be on a grass-fed model which is likely to provide more of a carbon sink that grain farming
and finally
4) that humans are not designed to be vegetarian and that there is not a single example of a traditional human culture obtaining *optimum* health on plant foods. We are a species that is *designed* to skim the highest quality calories (i.e. protein and fat) off of any ecosystem, despite the fact that the past 10,000 years has allowed us to diverge from that evolutionary path (and, incidentally, our population to grow significantly by shifting to plant-based calories).
I think people should be free to choose whatever they want to eat. But the vegan/vegetarian argument fails on an evolutionary basis and even on a scientific one when considering some of these complexities.
I should make one further point -- the fact that hunter gatherers and paleolithic peoples did not sustain high population numbers on animal-based foods is not evidence that modern humans cannot. Hunter gatherers and paleoliths did not have animal husbandry. We do -- that combined with private property ownership (including privatizing the oceans) is our best mechanism for ensuring the survival of species that matter to us for food.
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