Why you should eat meat - even if you hate factory farming

I agree that removing the 10% of animal products from your diet that causes the least suffering is not that important, and otherwise clear-headed EAs treat it like a very big deal in a way they don’t treat giving 10% less to charity as a very big deal (even though it only takes small amounts of base giving for the latter to be a far bigger deal). There is a puritanical attitude to diet that is surprisingly pervasive on the forum which I think is counter-productive.

Another commenter (Tristan) is right to point to other and second-order benefits of veganism, but some of the common ones I hear I don’t find persuasive. For example, it’s not clear to me whether the signaling value of being 100% vegan and strict about it (which many people now pattern match with being shrill and judgmental) is positive, or at least more positive than being 90% vegan (signaling that change doesn’t have to be all or nothing, that taking intermediate first steps is good etc.)

But this post’s title that ‘you SHOULD eat meat if you hate factory farming’ goes too far. I don’t find the case compelling. So upvoting and disagreeing :)

Interesting post.

As a vegan-for-the-animals for 27 years I agree that

- nutrition science is very complex and very primitive

- there definitely could be nutritional benefits to animal products (and downsides to avoiding them) that we're not seeing yet

- the vegan/animal rights movement is sometimes too dogmatic about vegan diets, and sometimes downplays the potential pitfalls

- caring for your own health is important and a moral thing to do, with potentially beneficial altruistic outcomes

- agreed that within omnivorous diets a lot of variation in terms of negative impacts on animals exists

- I also think there's possibly potential pro-animal bias involved in our assessment of the science (including by vegan health professionals). Motivated reasoning and wishful thinking could also make us not see potential downsides, averse effects in ourselves, and not communicate about them.

however

- i think the claim that veganism is "probably unhealthy" is too strong, and too vague.

- just like we need to take into account pro-animal/pro-vegan bias, we also need to take into account a carnistic bias (same here in the comments)

- the caveat about correlation/causation is really important (e.g. in the case of depression/mood disorders)

- even if adding animal products to your diet is healthier (it's definitely possible), does one need to go for maximum health if it causes a lot of harm to others? I understand most people will want to maximize, but it doesn't necessarily make it the most moral option. how far do we go in this? start eating other animal food groups (like insects or whatever) because there might be something healthy in there that we might be missing?

- leaving out whole food groups could not be the best option, but on the other hand, just like we don't know all the beneficial properties of and nutrients etc in many foods, we also don't know the bad ones (we could be avoiding a lot of damaging nutrients when we avoid certain food groups)

- when you write posts like this, please give enough consideration to the uncertainty, the present polarisation around the topic, the gigantic scale of the suffering, the fact that most people will gobble down this vegan-critical information with great gusto...

I started writing a long reply on the many parts of this I disagree with, and I may finish that over the weekend. In the meantime, I just have to ask: What on earth is going on with the fearmongering around vitamins and supplements?

First off, even the most dedicated vegans will tell you that to stay vegan you need to take medicine to not die - B12.

I don't think I've ever heard someone refer to a vitamin as "medicine" before, and the way you repeatedly do in this piece reads to me as some odd scare tactic. I think we're actually as an EA community really in favor of vitamin supplementation (just search "Vitamin A" on the Forum) and most people would not consider fortified foods medicine.

In my opinion, fortification is pretty amazing! The discovery of vitamins was pretty amazing! I think both should be celebrated, not stigmatized.

I'm reading the way you talk about this as weirdly "anti-science wellness influencer" coded, but am I missing something here?

This post assumes that the main reason for going vegan is due to your individual consumer impact. But there are at least three other, in my opinion stronger, reasons to go vegan:

1. Because evidence suggests that when we eat animals we are likely to view them as having lower cognitive capabilities or moral status (see here for a wikipedia blurb about it). My own experience is that I started thinking and caring about animals more after I stopped eating them.
2. As a social signal, to show to others that you object to this practice as a whole.
3. You just find it easier to live according to simple ethical principles rather than calculating the expected utility in every situation.

Consumer boycotts aren't often effective at putting industries out of business. Social and political movements are, and the above three points contribute better to social and political change.

In response to the health argument:
The argument seems to be primarily an argument about ignorance: we don't understand nutrition, so veganism might be bad for us in a bunch of ways that we don't yet know about. But any modern diet is pretty far from a 'natural' one, so I'm not sure why defaulting back to a normal modern diet is any better. I wouldn't worry about this myself, because the reality is that humans evolved eating a variety of diets in different places - our bodies have adapted to take on a bit of stress. 

But also, it's not that hard to cover most of the nutrients mentioned at the beginning of the post - I buy a multivitamin that's designed for vegetarians, thus has a range of vitamins in the right ratios, and combine it with omega 3, and I'm sure that I'm healthier than I was before I was vegan and I'm sure I'm healthier than the majority of the population too. So if you're willing to put in this amount of work, I don't think the argument applies.

Side note on muscles and oysters:
I think one could argue these are part of a vegan diet, if a vegan diet is one based on not harming sentient beings.

*edit to add: I also would take long-term studies on vegan health with a big grain of salt, since I think it's become dramatically easier to have a healthy vegan diet in the last 10 years, with better access to vitamins, fortified milks etc.

I'd like to point out that many of the articles you provided linked vegetarian / vegan diets to poor health outcomes were performed in China or global contexts. Globally, meat is quite expensive and therefore you could expect that correlational studies will find that meat intake is correlated positively with health outcomes simply due to income effects. I don't see that as particularly strong evidence that vegan / vegetarian diets are unhealthy when most existing research finds benefits for plant-based diets, especially for cardiovascular health.

Separately from the debate of veganism vs eating meat, we have strong evidence that high intake of fiber, low intake of saturated fats, and low intake of red and/or processed meats are all correlated with positive health benefits. Given that, my prior assumption is that a vegan/vegetarian diet (which is likely to be high in fiber, low in sat fats and have zero red and/or processed meat) is generally going to be healthier. It would take very strong evidence to the contrary for me to shift my mindset to believe that vegan diets are less healthy.

Finally, if you are going to consume animal products, aside from bivalves dairy probably causes the least suffering. Wild-caught fish might be more human than farmed, but substitution effects and a fixed population of wild-caught fish means that consumption of wild-caught fish is still going to result in higher demand for farmed fish. This analysis (If You're Going To Eat Animals, Eat Beef and Dairy — EA Forum) found that dairy has the "least suffering per kg of product." Dairy is also a great source of B12 and Calcium, which addresses two of the key nutrient deficiencies in vegan diets. Dairy is also healthier than beef, especially if you are consuming low fat dairy products.

You say that you put a disconcertingly high probability that plants are sentient, yet seem to understate this possibility for bivalves despite their nerve ganglia, which allow for nociception and make them biologically closer to the organisms we associate with sentience than plants.

I find your encouragement of backyard eggs to be particularly concerning. Keeping hens in backyards does not address important welfare concerns around unnaturally frequent laying and still supports the commercial breeding industry which commonly macerates and suffocates male chicks. The wild ancestors of domestic chickens (i.e., red jungle fowl) laid around 8 to 12 eggs per year, limited to particular seasons. Meanwhile, modern laying hens have been selectively bred to lay upwards of 300 eggs year-round, which is far beyond their natural reproductive capacity. This causes nutrient deficiencies (especially for calcium, which is taken from bones and eggshell formation), and increases the risk of egg binding and egg peritonitis, both of which are painful conditions. If you have the time and resources to keep backyard hens, you can probably afford to take a multivitamin to cover your bases.

Your recommendation with regards to wild-caught fish I think is oversimplistic. The WFI recently published a study which found that trout experience an estimated 10 minutes of significant pain when slaughtered by air asphyxiation. Standardised per kilogram, this equates to an average of 24 minutes of significant pain per kg, with upper estimates reaching 74 minutes/kg. The RSPCA estimates that other slaughter methods can take hours to induce insensibility. Commercial fishing also frequently involves the capture, injury and death of many non-target species, including crustaceans, sea turtles, seabirds, dolphins, porpoises, and even whales. It is not clear to me that the our impact on wild-caught fish can be summed up as “killing them earlier than they would’ve died anyway.” If you’re eating wild-caught fish for health reasons, you might want to be careful about exposure to mercury, PCBs and dioxins, which accumulate in fish tissues and biomagnify up the food chain.

Creatine and taurine are not essential amino acids. Our body synthesises them from essential amino acids (e.g., arginine, glycine, methionine, etc.). If protein intake is sufficient and varied, this is enough for most people, though can be a concern for infants and elderly people. The other nutrients you mentioned are often available in combined multivitamins. Specific formulations for vegans are especially helpful, and B12 supplementation in particular is inexpensive and highly effective.

You note that observational studies cannot establish causation when undermining evidence on the healthfulness of vegan diets, but appear to be less concerned about this when citing studies that are negative. You also rely on individual anecdotes as evidence that a vegan diet is responsible for x and y health problems, which contradicts your earlier cautious reasoning about correlation vs. causation. I think in general your use and interpretation of evidence/anecdotes reveal a vulnerability to confirmation bias in support of your premature conclusion that vegan diets are unhealthy.

While I agree with other comments that the animal movement often focuses too much on personal diets, this post actually makes the same mistake, but I think much more irresponsibly.

I believe that a world in which we encourage systematic violence towards sentient beings, even if implicitly, is counterproductive to our shared goal of ending factory farming.

"In fact, weight loss is a common side effect of a vegan diet, which could explain all or most of any health upsides, rather than being vegan itself."

This is more a point against your thesis than for it, I think. It doesn't matter if the ideal meat diet is better than the ideal vegan diet, because people won't ever actually eat either-this is just the point about how people won't actually eat 2 cups of sesame seeds a day or whatever. If going vegan in practice typically causes people to lose weight, and this is usually a benefit, that's a point in favour of veganism. Unless people can easily just lose weight another way-and they very much cannot as we know from how much almost everyone overweight struggles to get permanently healthy by dieting-it doesn't matter if the benefit from veganism could theoretically be gained by some non-vegan diet that you could theoretically follow. I guess the main counter-argument here would be if you think the existence of ozempic now makes losing weight in another way sufficiently easy. 

There was that RCT showing that creatine supplementation boosted the IQs of only vegetarians. 

My understanding is that the most rigorous RCT on creatine for cognitive performance found no difference between vegetarians and meat eaters and virtually no effect size in either case.

(Crossposted from my LessWrong comment.)

If you personally feel safer eating animals products, fine. 

If you don't want to follow a well-planned diet, also fine to eat omnivorously. 

But before encouraging others to feel unsafe about following a well-planned vegan diet, it's probably a good idea consider that the US Academy of Nutrition and Dietetics published in 2025 a peer-reviewed position paper that reiterates what they've been publishing for decades now, that well-planned vegan diets are healthy, and to explain why and how they would do that if, as you claim, the weight of the evidence pointed to expecting well-planned vegan diets to be a bad idea for health.

How would the world's largest organization of food and nutrition professionals manage to push through the peer review process, decade after decade, position papers that INCORRECTLY claim well-planned vegan diets are healthy?

"It is the position of the Academy of Nutrition and Dietetics that, in adults, appropriately planned vegetarian and vegan dietary patterns can be nutritionally adequate and can offer long-term health benefits such as improving several health outcomes associated with cardiometabolic diseases."

From https://www.jandonline.org/article/S2212-2672(25)00042-5/fulltext

If the AND should be expected to be biased in any direction with respect to vegan diets, we should expect it to be biased against veganism. Consider that it's very likely that most members of the AND are not vegan (just like in the general population), and the AND is partly funded by animal products industries:

American Egg Board’s Egg Nutrition Center

National Dairy Council

As for your opening sentence on the health section, "you need to take medicine to not die - B12", I don't think a B12 supplement is medicine. Factory farmed animals are routinely fed B12 supplements and people don't consider meat medicine. Salt is supplemented with iodine to prevent deficiencies, also not medicine. 

Discussing -as you do- what happens to vegans that forgo B12 supplements is besides the point (as would be to discuss what happens to people who go on a fast-food only diet). I can attest to the prevalence of a worrying number of non-rationalist vegans don't supplement B12 (In my experience something like a third or half of vegans don't supplement B12). However, everyone here on the EA forum likely agrees that if you are vegan you should follow good nutritional advice. And B12 supplements are inexpensive and convenient. 

On top of the others' comments on B12, it's worth noting that there's a common blanket recommendation for everyone over 50 to supplement B12, no matter their diet, because absorption gets worse with age. So it's strange to insist on lack of B12 and need of medicine as a problem only for vegans.

Reference: Institute of Medicine. 1998. Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline. Washington, DC: The National Academies Press. https://doi.org/10.17226/6015.

Interesting points! An important caveat is that, in addition to animal welfare, people do not eat meat/animal products because of the environmental impact, biorisks, social justice, etc.  Moreover, the whole world cannot eat off pasture-raised beef or "high-welfare" eggs, which complicates a bit what we ought to do as individuals. And even in the best scenarios of eating animal products, pasture-raised cows are often transported far distances with no water, cramped, etc., and slaughtered in problematic ways. "High welfare" eggs still require sourcing laying hens and male chicks being disposed of, etc.   No shame in doing what is best for you and your health, though! 

The question that is on every single EAs mind is, of course, what about huel or meal replacements? I've been doing huel+supplements for a while now instead of meat and I want to know if you believe this to be suboptimal and if so to what extent? Nutrition is annoyingly complex and so all I know for sure is like protein=good, cal in=cal out and minimize sugar (as well as some other things) and huel seems to tick all the boxes? I'm probably missing something but I don't know what so if you have an answer, please enlighten me!

Interesting post, curious if your motivation with this post is to promote that animal advocates eat animals? Anyway, I have a couple of objections here.

• I’m not convinced that vegan diets are inherently less healthy. The evidence cited is mostly observational and confounded, while large cohort studies and position statements from bodies like the Academy of Nutrition and Dietetics show that well-planned vegan diets can support good health at all stages of life. Poorly planned vegan diets can cause deficiencies, but a better direction to move towards is how to make them easier and safer. Robust supplementation, food fortification, cultivated meat, and clearer nutritional guidance/planning are some examples of better solutions.

• Not eating sentient beings generally minimizes harm more effectively than eating some of them. That is true both in the direct sense, since fewer beings suffer and die, and in the indirect sense, since it avoids reinforcing speciesism. Those second-order effects could easily outweigh any claimed benefits of selectively eating animals. For that reason, I still think the principle of avoiding the consumption of sentient beings wherever possible and practicable is the stronger position.

   

You might like this diet offset calculator, Kat: https://forum.effectivealtruism.org/posts/Bc6E6AeWesmeobeKq/beyond-go-vegan-a-video-introducing-omnivores-to-another

x-posted from Substack

Now, of course, being vegan won’t kill you, right away or ever. But the same goes for eating a diet of purely McDonald’s or essentially just potatoes (like many peasants did). The human body is remarkably resilient and can survive on a wide variety of diets. However, we don’t thrive on all diets. 

Vegans often show up as healthier in studies than other groups, but correlation is not causation. For example, famously Adventists are vegetarians and live longer than the average population. However, vegetarian is importantly different from vegan. Also, Adventists don’t drink or smoke either, which might explain the difference. 

Wouldn’t it be great if we had a similar population that didn’t smoke or drink but did eat meat to compare? 

We do! The Mormons. And they live longer than the Adventists. 

The Seventh-Day Adventist studies primarily looked at differences *between* different Seventh-Day Adventists, not just a correlational case of Seventh-Day Adventists against other members of the public. This helps control for a number of issues with looking across religious groups, which would be a pretty silly way to determine causation from diet to health. I believe the results also stand after a large number of demographic adjustments [2].

Finally, Mormons are predominantly white. Only 3% of Mormons are black. 32% of Seventh-Day Adventists are black. In the US, black people have a substantially lower life expectancy than white people [3]. Thus, it'd be unreasonable to look at naive life expectancies across two different religious groups and assume that lifestyle makes the biggest difference, when there are clearly other things going on.

[1] https://pmc.ncbi.nlm.nih.gov/articles/PMC4191896/

[2] https://pmc.ncbi.nlm.nih.gov/articles/PMC4191896/table/T4/

[3] Interestingly enough, this is not true across the rest of the developed world. For example, UK black people have a higher life expectancy than white people. I've never dived in into this discrepancy before so I'm not sure what the reason is.

Very interesting article. I agree that nutrition as a vegan is tricky- there can be limits to supplementation (although relatively cheap b vitamins and vegan omega-3 supplements are available online in my experience). I’d mildly disagree with you that gaining muscle as a vegan is ‘much harder’, pea-isolate protein powder and tofu (if you know where to get it) can be a nutritionally complete protein source, price competitive with even with chicken.

I do have a few issues with your list of (potentially) ethical aninal products:

1. Bivalves: I agree that these are likely to be unconscious. However, a lack of certainty could make this a problem given how many animals are necessary to make a meal, and given that the means of preparation often involve boiling said animals alive. Additionally these are small and expensive foods which probably couldn’t meet the nutritional needs of a large number of people cheaply.
2. Wild caught fish: The issue with this again is the number of animals involved. Some fish may have small brains, but you need a large number of individuals to make a meal. Given the extent of uncertainty around consciousness in the animal kingdom it feels morally risky to do so. I see the argument that these animals could die worse deaths from hunger or predation in nature, however I think there is a useful acts of commission/omission distinction in morality which holds up when talking about wild animal suffering. There is also uncertainty about whether animals lives in nature are net negative, if not then catching wild fish on an industrial scale is  pretty bad.
3. Cattle: I think your argument is stronger here (cows are large indeed!). I think particularly in relation to dairy. An omnivore could probably eat one cow a year in expectation, but may take 2-3 times as long to consume enough dairy to separate a calf and a cow. Personally I consume dairy for this reason, without going so far as to eat beef, but I realise the two industries are connected.

4. Eggs: I think it’s hard to know if an egg is ethically produced or not, given how poorly enforced and vague a lot of ‘free range’ standards are in reality. Also, without in-ovo sexing consumption of eggs necessarily involves a lot of killing male chicks which doesn’t sit right with me.

   Additionally, I’m not entirely convinced of the argument that vegans have worse mental health because of their nutrition. I think it’s as likely that vegans are more likely to be neurotic, self-critical, and politically liberal, all of which are highly correlated with anxiety and depression.

Thank you for trying your best to understand the world better, but please add more points on the health BENEFITS a vegan diet provides.

This post focuses way too much on the negative health correlations among vegans populations, ignoring the many negative health correlations in omnivorous groups--painting a picture that an omnivorous diet is *clearly* better 🙄 

To address each of your evidence-based points (ignoring the bro-science points):

- "Vegans/vegetarians had over twice the odds of depression compared to omnivores" Completely expected. We are aware of the horrible reality around us with tortured animals being treated like yummy products all around us. I'm surprised it's not 5x higher depression. 

- "Among those who lived to 80, vegetarians/vegans had higher rates of cognitive impairment: vegetarians had over 2× the odds of cognitive impairment" We have cheap Omega 3 algae supplements today. We know Omega 3 supplementation is extremely helpful in old age. This deficiency is slowly resolving itself in the vegan population--just as B12 did. Spread the word.

- "Vegans had over 2× the risk of hip fracture" Increased obesity in normal populations help protect against hip fracture. And just use calcium supplements--unless supplementing with dead animals is somehow more reliable?

 - "Total Meat Intake is Associated with Life Expectancy: A Cross-Sectional Data Analysis of 175 Contemporary Populations" Besides the article title--what exactly is it about their numbers that compels you to advocate for meat? The numbers they give are not straightforward, unless you just want to take this dude's word for it.

- "A small study found 26.5% menstrual irregularity in vegetarians vs 4.9% in non‑vegetarians. Low B₁₂ and iron can lead to anemia and ovulatory problems; low zinc may disrupt menstrual cycles; inadequate iodine or selenium can affect thyroid function, which is crucial for fertility." - Multivitamins are better than advocating for animal death.

Overall, extremely weak reasons to advocate for animal consumption, but thank you for highlighting the silliness of these commonly held ideas.

I know you put value on personal accounts, so just to give my own account, after 11 years of veganism, I feel way less depressed than when I ate an omnivorous diet.

Tempted to write a response post to this (which at the very least collates the responses in the comments re the various weak evidence it cites), especially given how much positive traction it's got on LessWrong. A worthwhile use of time?

Thanks for writing this Kat! While I don't agree with everything, the core argument (cluelessness about nutritional science means ancestral diets are a strong prior) was convincing to me.

I wanted to note how I updated my diet from this and additional ~3 hours of research:
- 100g/week of sardines: (due to reasons here)
- 150g/week of mussels: I agree with the post that they are unlikely to be sentient
- 2 eggs/week: My guess is that EU welfare level 0 (organic) actually means chickens possibly have a net-positive life. Lmk if you know of welfare concerns with organic eggs in the EU!
- Once per month cow liver: In order to cover the "red-meat" food group, I'm adding some cow meat as it seems to cause the lowest suffering of commonly available animals per kg. Why liver and not normal beef? Firstly, it has higher nutrient density, thus you need less of it. Secondly, organs were regularly eaten by ancestors, thus the ancestral prior is strong. Thirdly, livers are a byproduct of normal meat production and organ meat is often discarded due to low demand. Thus, buying livers likely doesn't increase demand for cows much.

I was already occasionally eating cheese beforehand; otherwise, yoghurt/kefir might also look good.

I'm happy to be convinced of changing this based on new evidence!

Thanks for sharing your thoughts, Kat.

A question that comes to mind is: If eating bivalves can give you the nutrients you think you might be missing on a vegan diet, why not just be vegan + bivalves? Why include more morally problematic foods like wild caught fish, eggs, etc? Or is it more about the sensory experience and social ease that comes from eating those foods? Thanks! 

I agree that nutrition science is not robust enough, but I have never been convinced by arguments against healthiness of a fully plant-based diet. 

As you note, vegans live longer in observational studies. 

Furthermore, trans fats and heavy metals are very likely to be bad for health. Consuming animal products exposes you to these. (A lot of) Saturated fat might also be bad for you and animal products have more of that. I agree that vegans might be missing out on some beneficial nutrients but there are also some harms avoided. I'm not sure which effect dominates.

What an interesting and nuanced article! I somewhat agree with many of your points, although I think we could bypass all of this by focusing on the opportunity of cultivated meat. That's really the only solution that matters for animal welfare, in my opinion. 

 

Thanks for the post, Kat. You are assuming that eating more animal-based foods decreases animal welfare, but I think it actually increases it due to effects on soil animals for my best guess these have negative lives. I am very uncertain about this. However, it is at least clear to me that eating more animal-based foods increases animal suffering if it increases agricultural land, and animal-based product generally require more agricultural land. The decrease in the living time of wild animals is way larger than the increase in the living time of farmed animals. I would be curious to know your thoughts on this.

Does anyone have a good link a discussion of reasons that a strictly vegan/vegetarian diet might outperform light consumption of animal products (e.g., one serving/day) from a health perspective? 

I can envision the reasons why a strictly vegan/vegetarian diet might outperform a mostly vegan/vegetarian diet plus some red meat or processed meat -- given that those are suspected or known carcinogens. Why it would outperform the standard American diet is obvious, but that isn't the relevant comparison here. I don't recall seeing a good affirmative case for zero as opposed to modest meat consumption in general.

I find somewhat convincing the argument that there's at least some risk of downside from complete omission of a major food group that has been a significant part of the diet.^[1] But that's not enough to compare the potential risks of a vegan or vegetarian diet to the potential risks of a diet with some animal products.

1. ^{^}

   As one of the cited articles notes, "a human animal consuming a body of another animal gets practically all constituent compounds of its own body." So to the extent that there exists something positive in food that we don't yet know that we benefit from, meat is likely to have at least some of whatever it is.

The disagreements below this post with "X" was quite expected but the post in itself was quite unexpected. I agree to the content btw!

I was initially triggered when I saw the article, but I decided to read it with the intention of challenging my own views, and I’m very glad I did. Thank you for writing such a courageous post. I believe I agree with high majority of your points, and I’ll be more mindful about my supplementation and probably start incorporating bivalves into my diet. Once again, I truly appreciate your courage and good intentions in writing this piece. 

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