It is important for animal advocates to be intellectually honest about the balance of the pros and cons to health from abstaining from animal products (being vegan). If they are not intellectually honest, their arguments will be discredited and discounted in the future by the general public.


Unfortunately, I think some of the popular medical doctors advocating for plant based diets, including Neal Barnard and Joel Fuhrman, have gotten a reputation for only presenting one side of the evidence. Similarly, I am not sure if the 2018 documentary Game Changers helped or damaged the arguments for plant-based diets since it was widely reviewed as insufficiently sober in its handling of a complex subject ( If I am wrong about this I would be happy to be corrected.


I have heard arguments recently that one of the most important components of healthy aging is minimizing sarcopenia, and this cannot be feasibly done without large doses of protein, including animal protein, spread out throughout the day ( These arguments are being advanced by respected academics, who are also arguing against school lunches going plant-based. 


If animal advocates are going to suggest that the public abstain from consuming animal products, I believe they should address the sarcopenia point, and other similar points, directly and credibly. If this has already been done, I apologize, and would request that someone direct me to those materials. If it has not, I would like to suggest that this is a void that would be helpful to fill.





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My main concerns regarding vegan diets is the lack of creatine (and its potential effect on IQ) as well as children being raised as vegans (based on my minimal research, it seems that vegan kids tend to be shorter).

As someone who doesn’t eat meat at the moment, I’ve been debating eating meat again because 1) I don’t want it to negatively impact my intelligence/memory and then I make less progress on ai alignment 2) I’d be concerned it negatively impacts the growth (in all aspects) of my future children.

In general, I’ve been quite underwhelmed by the level of research (and written–up analysis) on the above concerns. It seems that lack of creatine does lower IQ, and I’d like more understanding as to whether the supplements actually work  to resolve that issue (or is absorption a problem?). That said, I’ve read that meat eaters typically only get about 1g/day of creatine and I supplement 5g/day (my guess is that beyond 3g you probably don’t get more IQ boost).

For children, I’m having a hard time imagining the quality of research will be sufficient by the time I have kids, so I will likely default to having them eat a mediterranean diet.

Can creatine be found in vegan supplements?

Interesting that some people disagree. Would love to hear what you disagree with and if you can change my mind with research that goes against the above. Otherwise I have to consider that you either disagree with the above being important for you specifically or you think the claims I made are wrong.

I mostly agree with the spirit of this post because my experience with vegans is that they’ve been overconfident in positive health impacts from veganism (essentially hearing what they want to hear from the research) because of motivated reasoning and the underlying belief that animal suffering trumps any potential negative health impacts. That very well may be true, but it has always been difficult for me to trust vegans claiming good health impact (meat eaters are potentially worse, to be fair) because I’ve always had the impression that they aren’t being as rigurous and intellectually honest as possible.

If you want more people to become vegan, easing these fears is necessary. Otherwise you either get people like me who waited years to stop eating meat or people who leave veganism as soon as they form a long-term relationship or get kids.

The quality of research is already there: See my comment here.

I'm not aware of any newer studies on creatine after the original one that spawned this belief; I will point out the original studies were likely aggressively p-hacked, showed impossible effect sizes, and make very little sense because brain creatine levels are not substantially different between vegetarians and vegans.

Still, it's not completely out of the question there's a real effect. We still want to avoid the fallacy of the one-sided bet. It's definitely possible that vegetarianism causes a drop in . But given vegetarianism seems to lower blood pressure, LDL cholesterol, and obesity rates, I'd be willing to put money on the exact opposite. A healthier kid is a smarter kid, and vegetarianism seems to have positive effects on health in general.

If you're still skeptical, over-the-counter creatine is extremely cheap (and has benefits for physical performance anyways). Trying to get rid of LDL cholesterol, on the other hand, is pretty hard.

As I said in my comment, I already supplement 5g/day (I've been doing this for 15 years). My concern about supplementation is that it's not clear to me that supplementation works wholly. Even in supplementation, different forms of creatine seem to have different levels of effect. With respect to creatine's impact on cognitive performance:

Three papers suggest that creatine may improve cognition: Ling 2009 found that creatine supplementation may improve performance on some cognitive tasks, McMorris 2007 found that creatine supplementation aids cognition in the elderly, and Benton 2010 found that in vegetarians, creatine supplementation resulted in better memory. However, Avgerinos 2018 found that while creatine supplementation may improve short-term memory and intelligence/reasoning of healthy individuals, its effect on other cognitive domains remains unclear.

Anyways,  I'm going through papers on Elicit using the prompt, "Does the vegan diet lead to shorter children?" I'm finding mixed results, some say no, some say yes. For example,

Vegan diets were associated with a healthier cardiovascular risk profile but also with increased risk of nutritional deficiencies and lower BMC and height. Vegetarians showed less pronounced nutritional deficiencies but, unexpectedly, a less favorable cardiometabolic risk profile.

With regard to differing forms of , the article you linked notes:

Despite these minor differences in processing, each of these forms is probably equally effective when equal doses are given.

Which is understating things a bit: All the minor variants will be identical after dissolving in the body -- anyhydrous creatine will become hydrated, and particle size is 0 after the creatine has dissolved. The only (minor) difference is that micronized creatine will dissolve slightly faster if you mix it with a drink, because of the smaller particle size. This can be mildly convenient, but I've never been bothered by the monohydrate being too slow to dissolve (it's almost instant for both forms).

With respect to the impacts on cognitive performance, Gwern completed an in-depth look here. Most important is the section on publication bias; the authors of these papers failed to replicate their results several times, but these failures were never published. Gwern concludes (and I agree) that creatine almost certainly doesn't affect intelligence in nonvegetarians, and has at best

The study you quote at the end about vegetarianism has a sample size in the low dozens, and I wouldn't put much stock in it. The large meta-analyses of this all find better life expectancy and health markers in vegetarians/vegans. The one important exception is B12 (for which the study you cite finds a deficiency in vegans). Luckily, th

is can easily be fixed by supplements.

I think it's probably best to avoid listening to "celebrity doctors" and documentaries. This blog provides some good evidence based advice for vegan nutrition IMO:

Good article about protein here:

Thank you! This exactly what I was looking for.

If you're still interested in this, I found another extensive article about vegan protein:

I'm curious how consumption of free amino acids changes the calculus, for example, BCAA's, glutamine, lysine, glycine. Meanwhile, Peter Attia is a strong advocate of exercise, and it's worth looking at the actual dietary recommendations for avoiding sarcopenia, I think they're about 10 grams up from typical daily protein requirements, but you can correct me. Anyway, increased exercise and compensation of the diet with a protein supplement (pea or soy protein) would meet published standards for avoiding sarcopenia, assuming a varied vegan diet containing legumes and grains and plant milks.

Of course, this can be a rabbit hole of "well, soy is a pseudo-estrogen", "beans give me gas", "I'm on a low fodmap, gluten-free diet to avoid leaky gut syndrome", etc. Yeah, I get it.

Besides that, there's also genetic individualities that determine different dietary requirements, differences in how a person metabolizes fats, and stage of life matters as in the case of children or the elderly.

If you're dealing with diabetes-like blood sugar or insulin levels, there's more concern about food sources that trigger rapid blood sugar changes, perhaps a high-protein diet helps there, or perhaps not.

Your gut micro-biome could be altered to improve your metabolism of foods and help you cope with a different diet, or improve your nutrient uptake from your current diet. Or not.

As far as your seeking good evidence, I think you need sources that offer more nuance and I hope you find them.

I think the central point is that animals carry moral weight and that we should act accordingly, not that there are no trade-offs to to the health and pleasure of humans from abstaining from using animal products. It's not as if, given a scientific consensus that the optimal diet at our current tech level includes meat, animal advocates would cease advocating for abstaining from using animal products. Assigning animals a significant moral weight means that such very minor drawbacks to humans become a rounding error next to the major harms to animals.

Animal advocates who say that cutting out meat will not harm your health or will improve it, aren't presenting an unbiased argument about nutrition literature and human health. The conclusion is motivated by not wanting to hurt animals. Research that validates or debunks this motivated conclusion may be useful to animal advocates insofar as which vitamins and protein powders they might recommend, but it wouldn't sway the central point.

I agree that is the central point. I also agree going vegan is the morally correct thing to do even if it comes at a cost to health.

My point is that if animal advocates have a strategic goal of reducing consumption of animal products, I think they would be better served by being intellectually honest and sober rather than untrustworthy.

With regards to protein: studies consistently show getting enough protein to prevent sarcopenia or other diseases is not especially difficult, and in fact most people get substantially more than the recommended daily allowances. Also important is that consuming animal protein is positively correlated with all-cause mortality, while plant protein is negatively correlated. From what I can tell, though, this is probably because fiber is confounding the results.

Moving on from observational studies and to randomized controlled trials, it's unclear whether protein even has a meaningful effect on muscle strength, let alone something like lifespan, with some studies finding little or no effect from supplementation. It's really not clear protein would help with sarcopenia from the studies, but we'd honestly expect null results from theory alone. We know from surveys that the limiting factor in most people's muscle strength is physical activity, not protein. Most people get more than enough protein, and excess protein consumption turns into fat, not muscle. For most people, protein supplementation just can't help because they aren't moving enough.

The primary dietary determinants of health seem instead are mostly:

  1. Polyunsaturated fatty acids (found in fish and vegetable oils)
  2. Fiber (typically supplemented with psyllium husk)

I'm busy, so I'll stick to looking at the evidence base we've acquired just on fiber supplementation. Here's a bunch of insanely overpowered observational studies with sample sizes stretching into the hundreds of thousands, all showing reductions in all-cause mortality. Meta-analyses of RCTs? We've got those in spades.

There is a reason every doctor's dietary advice is exactly the same: "Replace refined with whole grains, avoid saturated fats and replace them with unsaturated fats." The reason is because we have million-person studies showing these interventions reduce heart disease. Note that heart disease is by far the leading cause of death among the elderly; sarcopenia doesn't really kill, although it does make life substantially worse. And importantly, both of these are substantially more common in plants than in animal foods, which offers a pretty good explanation for why vegetarians seem to live longer, even after controlling for confounders. And also for why vegetarian diets seem to improve health markers in RCTs.

If you're wondering whether the above studies  leave some room for including fish in your diet: My guess is yes, pescetarianism is likely to be slightly healthier, because of the aforementioned effects of polyunsaturated fats (including omega-3 fatty acids). This is why doctors also recommend the Mediterranean diet a lot, although it's not clear how much of the effect comes from fish and how much from vegetables. Omega-3 supplements definitely help.

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