Was looking into this because of that recent Paul McCartney article that was shared, and wanted to share what I found:
Here’s a good breakdown of differences between vegan & vegetarian diets in terms of climate impact: https://www.nature.com/articles/s43016-023-00795-w
Emissions:
Vegan:............. CO2: 2.16, CH4: 04.39, N2O: 0.71Vegetarian:........ CO2: 3.33, CH4: 20.21, N2O: 0.98medium meat-eaters: CO2: 5.34, CH4: 40.88, N20: 1.73high meat-eaters:.. CO2: 7.28, CH4: 65.40, N2O: 2.62
So vegans have 30% of the emissions as high-meat-eaters, and the differences between vegans and vegetarians are significant with regards to their emissions, particularly methane emissions due to the significantly higher consumption of cheese by vegetarians.
(EDIT: it has been suggested it’s worth clarifying that vegan diet having 30% CO2 emissions means that there was a 70% reduction in CO2 emissions, and that methane emissions were reduced by 93% going from high-meat to vegan.)
Vegetarians ate significantly more cheese (30 g / day) than even meat-eaters (19 g / day), despite eating less dairy overall otherwise.
Also should be noted that there is a big gap between biodiversity impact between vegans and vegetarians, with vegetarian diets causing nearly double the number of species extinctions per day than vegan diets.
I was surprised that water use was so similar between vegans and vegetarians considering how much cheese vegetarians eat.
I still would recommend a vegetarian diet to meat eaters, as it’s still a massive improvement (and in my experience, it’s easier to become vegan once vegetarian), just thought it was interesting to actually quantify differences between veganism and vegetarianism in terms of climate impact.
I eat a low-meat diet. I started with not eating pigs (too smart), then only eating meat one day a week, then I cut out cows because they’re just giant puppy dogs. I’m down to mammal flesh maybe 3 times a year (generally sheep or goat) and fish or poultry more often.
I’m not fully vegetarian because I already have a history of restrictive dieting, so I don’t want to start reading food labels for surprise chicken broth or whatever. However, I’m vegetarian enough that I have a vitamin B12 deficiency if I forget to take my supplement.
Anyways, what I’m trying to say is even if you’re not perfectly vegetarian or vegan it’s still better for the environment than having a steak every night, so baby steps if you need it.
absolutely - the study also looked at and compared low, medium, and high meat diets precisely to quantify those differences (and they are significant!)
if you are vegetarian, you shouldn’t have a B12 deficiency if you’re still eating eggs or dairy, though - that’s a bit surprising, I would only expect B12 deficiency in people who eat a non-fortified vegan diet (or similar diet like fruititarian where there is no source of any animal products).
I would maybe talk to a doctor about that 😅
also, proud of you not spiraling into restrictive dieting - that’s very healthy and inspiring
Thanks. I did talk to my doctor about the low B12 and she said that it was a combination of low baseline B12 and a new medication I’m on that further depletes my B12. So, supplements are my friend.
(Also, low B12 feels wicked weird, all sorts of odd nerve stuff in my hands was my clue, and it cleared up quickly after I started supplements.)
There’s an element that always misses from these assessments for some reason. Fishing. Mass fishing is one of the greatest destructions to the environment. And the oceans account for around 72% of the world’s oxigen production and nothing on land or everything on it combined achieves as much carbon capture as the oceans do.
And we’re destroying them at a faster rate than we are doing to anything on land.
I would suggest that instead of getting too bogged down in statistical data which will always have a lot of distorted information through how averages are obtained, people should learn how energy is exchanged through the trophic levels. Learn how biomagnification inflates every issue, from accumulation of toxins and chemicals, to energy loss and waste. The larger the animal, the larger the inefficiency as a redundancy, if I may. This logic can also be applied to Flora, not just Fauna. Ideally we should generate most of our sustenance through the lowest trophic level possible. The microbial and bacterial one. That would be where Precision Fermentation can play a great part in our futures.
But starting with understanding how predation systems were formed in Fauna is a great way to understand the trophic balance. It didn’t start by having carnivores first, did it? What would they consume? Flora? The fact is that having ambulant organisms which could evade many circumstances and weather events allowed them to reproduce beyond what the local Flora could allow them to consume, which resulted in them having to start preying on each other as result of induced scarcity.
Lack of self-regulation is the overarching flaw in the design. Once Fauna emerged, the rate of extinctions of both Flora and subsequently Fauna accelerated drastically, and so did changes in climate, obviously.
This is why I agree with the people who criticise Darwin for the use of the word “Evolution” as a descriptor in his thesis. It suggests “betterment” or “improvement”. Which from the insurgency of Fauna alone, we can attest that the world did not improve from it. Regarding sustainability alone, quite the contrary. “Transformation” is more accurate to describe what is always occurring. Mutations and subsequent adaptations transform the world. As if that constitutes Evolution… well… a problem can also evolve, I suppose.
Entropy, I guess…
Chaos is the architect of the scavenger’s rule of the wild.
There’s no hierarchies in Nature. The trophic levels merely refer to energy source in the chain - well, a tridimensional Web would be a more accurate visual discription than a chain.
But it would also make the microscopic forms of life the most valuable, if one wanted to place value to establish hierarchy. Which would be a silly endeavour to begin with. But a less silly one than a top as figment with a lion standing there. There is no top. Everything stems from the center and returns to it eventually.
But we as a species are nothing but a continuation of that fundamental flaw. We can’t achieve self-regulation, and ultimately we will cause resource collapse, which will cause scarcity, which will cause humans to prey on each other. This is our design. Or the inherent flaw in our design, like in all Fauna. One we’ve repeated incessantly through our brief recorded account we call history.
We just never did it at this rate and or everywhere all at once.
Now, how do we achieve self-regulation as a species? Theoretically it is possible, but in practice we can’t seem to get there.
We always get to the “tragedy of the commons”. Read up on this if you haven’t. It’s the feedback loop in our behaviour that makes us always race to the bottom basically.
As to your post, if you allow me to suggest, it would make more sense in one of the several environmental communities or even the solar punk ones across the lemmyverse.
Veganism as a word has lost all meaning by this point, but it is supposed to merely be a consideration for sentience when reduced to its’ most basic construction.
I don’t believe in the existence of consciousness. As it stands it merely seems to be meta-cognition, at least everytime someone tries to describe it. But cognition stems directly from sentience. Which stems from the sensorial experience. Which is verifiable. And why we can’t quite place it with the animals in the bivalve category. It’s too rudimentary beyond the management of those two valves.
But I’ll leave on this note, regarding sentience…
I have congenital anosmia, which means I’ve never smelled. If I were to try to think of a smell, it would be like trying to picture a colour I’ve never seen. Which led me to a thought experiment quite a while back in my life…
If a baby was born with nervous damage and never possessed any single one of the five senses, and if we kept this child alive… how could this baby have a single thought be formed? Out of what?
This is why I don’t believe in consciousness. We are nothing but an input-output system. And choice does exist somewhere in there. I just don’t call it “Free Will”. Too many things wrong with both of those words alone and even more when put together to describe what we’re trying to describe. The subatomic reality doesn’t suggest a predeterministic model. We, at our core, are as what reality seems to be, a randomising procedure. Another agent of chaos in the seemingly eternal entropy that is the universe. Let us just not call that free, when everything exists in condition to everything.
Anyway… when I write such long comments (which is too damn often!!), I never know how to finish. I always feel like apologising. So… sorry for the long one.
And if you read this far, I thank you for the attention you’ve given this fool.
According to the emissions you posted that 30% is only in CO2. For Methane it seems more like 8% (rough estimate. Need to get ready for work and can’t put much time in) and methane is worse for the climate than CO2 afaik. 30% could easily be dismissed as not enough to switch to a vegan diet by those considering it for the climate.
just going to lay out the maths to make it easy to follow along:
Carbon Dioxide
vegan CO2 emissions is 2.16 g / day
high meat-eater CO2 emissions is 7.28 g / day
vegan CO2 emissions is 29.67% (2.16/7.28) of high meat-eater CO2 emissions, that is a difference of 70%
this means a vegan diet has 70% fewer CO2 emissions than high meat-eater diets
Methane
vegan CH4 (methane) emissions is 4.39 g / day
high meat-eater CH4 emissions is 65.4 g / day
vegan diet has 6.7% of the methane emissions as high meat-eater (4.39 / 65.4), that is 93.3% less.
Conclusions
I wouldn’t characterize the take away for both a 70% reduction in carbon emissions and a 93% reduction in methane reduction as it’s not enough to merit changing diet - quite the opposite!
For comparison, taking a train instead of a domestic flight would reduce emissions for that journey by 85%, taking a train instead of a car for medium distances saves 80% of emissions, and taking a bicycle instead of a car for shorter distances saves 75% of emissions (source),
When I switched to an electric vehicle, I only saved 56% of emissions compared to driving a brand new gas car (probably saved more since I stopped driving a much older gas car). You can run your own gas emissions calculations here. Based on what I’m reading, electric vehicles tend to reduce emissions between 50 - 70% (part of this is about how much more efficient they are with energy use, being able to reclaim energy during city driving from braking and coasting reduces waste compared to a gas vehicle).
So a vegan diet is maybe comparable to bicycling instead of driving a gas car, better than switching to an electric vehicle.
Yes that’s what i was saying. In your post you said 30% when it’s really more 10% and meat eaters are grasping at every straw not to change diet so i just wanted the short percentage you gave to more reflect the truth. That’s all. I’ve already switched diet like a year ago and i want more people to follow. Also going vegan is a lot more difficult than taking the train instead of the car
I think I’m confused by your response … the original article says a vegan diet has 70% fewer carbon emissions than a high meat-eater diet (it’s 30% of the meat diet) …
If you have $100 and I have $30, I have 70% fewer dollars than you, I have 30% of what you have. That’s a dramatic reduction, I don’t think the even more dramatic reduction in methane emissions will be any more convincing - to be honest I don’t think any of this data will convince anyone to become vegan, most likely. Changes to diet like that are usually more emotionally motivated than rational.
I couldn’t tell, but it seemed like you were implying that the carbon emissions are only a 30% reduction or something, I’m not sure how else to interpret your seeming belief that this isn’t a significant enough reduction in emissions …
I do think a car is more impactful than a diet in terms of emissions created - an efficient, new gas car will emit 400 g CO2 / mile, which means even a mile of driving will far strip the 7 g daily CO2 emissions from a high meat diet.
I believe they are suggesting that people may see your statement at the end of your OP where you say a vegan diet has only 30% of the emissions as total emissions, not just the co2 emissions.
The other user is suggesting making it more clear that there is also a 90% reduction in methane gasses, which can be missed by a user who is not carefully examining the data.
I myself would suggest phrasing the lower emissions of vegan diets in terms of their total reduction instead of the percentage they use in comparison, as the reduction percentage is a bigger number, which sadly I would consider more psychologically effective despite it being the same information shown in a different way.
I.e, 70% less feels like higher impact compared to only using 30% as much.
that’s a good suggestion - I edited the OP to make that clarification; I agree that “30% of emissions” is harder to immediately understand than “70% fewer emissions”. We can’t ignore psychology if we are trying to be persuasive.
It’s not clear to me how we should think about the impact of methane gases - on the one hand they have a greater warming effect, but on the other hand they stay in the atmosphere for much less time (12 years) and overall contribute less to global warming than CO2 (which stays in the atmosphere for hundreds of years). It actually looks like nitrous oxide is an even bigger source of warming, and fertilizer inefficiencies by growing crops to feed animals is a major source of released N2O, though this is comparing CO2, CH4, and N2O tonne-to-tonne, it might be better to know how each contributes according to the actual amount being emitted …
Either way, it should be abundantly clear that a vegan diet does reduce greenhouse gas emissions of all kinds significantly and is something actionable anyone can do if they want to reduce their footprint (esp. important for Americans and people living in developed countries where over-consumption is real).
Though I personally think individuals deciding to become vegan to solve climate change is like asking individuals to make donations to end poverty - it’s not enough and won’t solve the problem, we need much larger social and structural changes so that by default everyone is making healthy climate choices because it’s the easiest, cheapest, and most preferable option.
For comparison, it’s very hard to live without a car if there is not sufficient public transportation infrastructure. Demanding someone in a car-centric city to live without their car and just take the bus obviously misses the point: we need public transportation infrastructure, the problem isn’t that Bob isn’t willing to hop on a bike and risk his life cycling 10 miles to work every day on a stroad because it’s faster to cycle 10 miles than to wait several hours for the bus.
If Bob wants to do that, power to him - but we should be realistic and recognize we aren’t going to solve climate change this way (nor is it particularly kind or reasonable to Bob, even if his behavior is considered morally exemplary).
Regarding climate change specifically, I just want to put these numbers out there as well…
Is it 14%, 18%, 24%, 34%, 51%, 53%, 66%, 87%, or 118%? There are a whole lot of percentage figures associated with the climate impact of animal agriculture. In this article, we will examine why there are such wide discrepancies and where the truth actually lies.
At Climate Healers, we’ve been saying 87% and now 118%, while most others seem to be stuck on 14% at the other end. So, what is the truth behind these numbers?
Two Questions
The two main questions around which scientists have been compiling animal agriculture’s climate impact estimates are:
A) How much of the annual climate impact is caused by animal agriculture?
B) How much of the cumulative climate impact is caused by animal agriculture?
While Question A is concerned with the rate of change in warming, Question B is concerned with the totality of warming since the pre-industrial era.
Where the Truth Lies
In reality, the estimates for both questions should take into account all 12 emissions components, not just a subset of them.
If we use ERF as the metric of choice, we can augment the 66% estimate with a COC component to answer Question B.
In order to answer Question A, we need to compute the derivative of the answer to Question B. This analysis is being conducted at the moment and we will report on our findings shortly.
…and the follow-up: Where the Truth Lies
the problem is that “opportunity cost” is a theoretical savings that isn’t being extended to other kinds of emissions, they aren’t looking at what carbon opportunity costs exist if we sequester carbon in other ways, e.g. an equally implausible alteration as ending all animal agriculture and replacing the land used for animal agriculture with carbon sequestration would be to eliminate cars entirely and to replace parking lots with trees … but they only look at animal agriculture to determine the relative contribution to climate change … it’s not surprising to learn Climate Healers is an organization dedicated to pushing the idea that animal agriculture in the main cause of climate change, and that veganism is the only solution to climate change. These are activists, not scientists.
If a brand new, efficient gasoline car puts out 400 grams of carbon dioxide per mile it is driven, and a high-meat diet puts off 7 grams of carbon dioxide per day, I would imagine that cars contribute much more to carbon emissions than diet.
Current estimates are that about a quarter to a third of greenhouse gases emissions come from food production (including animal agriculture). Climate Healers suggest including other emissions that are not commonly included for good reasons, for example carbon dioxide has a very long atmospheric lifetime of over 100 years, and reducing CO2 emissions will be crucial to preventing climate disaster … bringing up black carbon that has an atmospheric lifespan measured in days is not helping create a more clear picture - it distorts rather than clarifies. I trust the climate scientists’ choice to focus on carbon dioxide, methane, and nitrous oxide emissions as the main greenhouse gases of concern when looking at the impact to the climate, especially when you consider that this Climate Healers article is written by the founder, Sailesh Rao, who has no scientific background or education in climate science, and who has acted as producer on several films that have been criticized as sharing misleading or false statements, e.g. he was a producer on What the Health:
Martijn Katan, emeritus professor in nutrition from Vrije Universiteit Amsterdam, called the film “propaganda”. Katan says What the Health? exaggerates the health risks of meat, eggs and dairy, and dangerously claims veganism prevents or cures many diseases, like cancer or diabetes.
and was a producer of Cowspiracy which made false claims about the contribution of animal agriculture to climate change:
Doug Boucher, reviewing the film for the Union of Concerned Scientists blog, disputed the film’s assertion that 51% of global greenhouse gases are caused by animal agriculture. He described the 51% figure as being sourced from a 2009 Worldwatch Institute report by Robert Goodland and Jeff Anhang not from a peer-reviewed scientific paper. He claimed to have observed methodological flaws in Goodland and Anhang’s logic, and said that the scientific community formed a consensus that global warming is primarily caused by humanity’s burning of fossil fuels. He stated that the scientific consensus is that livestock contribute 15% of global greenhouse gas emissions, far lower than the 51% stated by the film and the source article.
The actual evidence I can find from peer reviewed, scientific sources indicate animal agriculture contributes a minority of the relevant greenhouse emissions we should be concerned about. Emissions aren’t the only environmental impact of animal agriculture, and it’s abundantly clear that veganism is a way to improve the environmental situation (it’s better on every mark: personal health, ethical considerations, lower emissions, less water and land use, lowered species extinctions, etc.).
But this leads me to be puzzled why, given all the evidence that veganism is good for you and good for the planet, someone like Sailesh Rao feels the need to dedicate himself to distorting the truth and exaggerating the impact of animal agriculture on the environment or health … Given his books which betray religious interpretations of the environment and veganism, the motivations for distorting facts are likely personal, and it’s unfortunate because his unwillingness to respect evidence or science undermines his message and paints veganism as an extreme diet that cranks and quacks push.
Veganism is in much better hands with actual medical doctors and climate scientists who have carefully accumulated the evidence that shows the diet is healthier and better for the environment than the alternatives. Science and evidence allows anyone from any faith or creed to accept the truth as true; pushing veganism with falsehoods and distortions from a religious perspective only weakens the movement.
they aren’t looking at what carbon opportunity costs exist if we sequester carbon in other ways, e.g. an equally implausible alteration as ending all animal agriculture and replacing the land used for animal agriculture with carbon sequestration would be to eliminate cars entirely and to replace parking lots with trees
How would you even account for this? You couldn’t count it as part of the carbon opportunity cost of fossil fuels, as some cars are electric. You couldn’t count it as part of the carbon opportunity cost of industry, as the industry that makes the cars is not responsible for constructing the parking lots. You would need to look at every aspect of car culture from mining the materials to manufacturing the cars to constructing the roads and parking lots and determine how much deforestation is involved in every step of the process, which would be no easy feat, especially as the ratio of gasoline to electric cars is now changing relatively rapidly and the footprints of these different types of cars would differ as a result, and then calculate the carbon opportunity cost of cars on the whole as a separate category (which would make the totals add up to more than 100%, as there would be overlap with the footprints of fossil fuels and industry, for examples). If you wanted to calculate ONLY the carbon opportunity cost of the land area used for parking lots not being forested, then that would be a much easier calculation, but it isn’t really fair to criticise Sailesh / Climate Healers or the sources that they cite for not running those numbers; that is a very specific climate footprint to track compared to agriculture, industry, forestry, etc.
if you are going to estimate what percent of emissions are from animal agriculture vs transportation by looking only at “carbon opportunity cost” of animal agriculture and not doing anything to estimate the equivalent carbon opportunity cost of transportation, doesn’t that create obvious problems for the comparison?
and yes, it is fair to criticize Sailesh for not considering carbon opportunity cost of other sources of greenhouse gases when making claims about animal agriculture being the number one contributor to climate change on that basis, that’s my point
here’s an analogy: what if someone only looked at CO2 emissions from cars and animal agriculture, and ignored methane emissions entirely from animal ag? Wouldn’t you feel that the claim that cars create more emissions on that basis alone leaves out important information? Since methane is a significant greenhouse gas, and large amounts of it are produced by animal ag, to be intellectually honest you would want to measure and compare all significant greenhouse gases from both cars and animal ag to make a real comparison.
My point was just that: you can’t calculate carbon opportunity cost of animal ag and not do anything to calculate something equivalent for other sources of greenhouse gases (like transportation) if you are being intellectually honest and are actually trying to make a comparison.
Considering Sailesh’s past associations with intellectual dishonesty, however, it isn’t surprising to see that here as well.
Here you can see the numbers without the COC included (X% + COC), so that is a more “apples to apples” comparison…
I haven’t actually done the measurements and repeated all of the calculations, so I can’t verify these or any other numbers, but from what I observe in the world, “common sense” suggests that animal agriculture does in fact have the largest ecological impact. When we consider the aerosol emissions from coal and oil, the ERF (not necessarily GHG emissions) of animal agriculture being greater than that of fossil fuels doesn’t seem like much of a stretch. Ultimately it doesn’t matter so much if the numbers are off; both the exploitation and non-human animals and the burning of fossil fuels will need to end, and the former is much easier to end quickly with minimal disruption to infrastructure.
