[kartoffelmos]

Animals don't synthesise B12, bacteria does. Animals cumulate it from eating food grown in soil. Industrial farming often require B12 to be added to animal feed as a supplement as they don't graze (as much).

Give this a second thought: humans don't synthesise B12 either.

[ada1981]

Yes in modern times there is no need to consume animals for b12, you simply need to eat b12 fortified foods.

I’m not arguing to go back in time, or shaming our ancestors.

I’m saying that in modern times, there is no reason to consume animals, and the B12 from eating dead animals is most often via supplementation anyway.

So it’s just giving a supplement to an animal and then killing and eating the animal when you could just take the same supplement.

I’ve been vegan 25+ years, am in the top 1% of physical health, have a biological age of 32 (I’m 44), regularly compete as an athlete in national level competitions, can hike hundreds of Km in the mountains at a single clip; and rarely ever get sick.

[doctordemen]

> Animals don't synthesise B12, bacteria does.

Yes, that's technically correct.

> Animals cumulate it from eating food grown in soil.

No.

Animals provide a hospitable environment (gut) for said bacteria to exist and synthesize. So while technically the animal's cells are not the ones directly synthesizing B12, the bacteria and animal gut are working in harmony to do so.

These facts are tangential to my point. The commenter I responded to said that people don't need to eat animal products to live at optimal health, which is laughable, and this is an incredibly clear example of why. A quick google search will illuminate the dangers of B12 deficiency.

And one more thing to consider, if humans coevolved with the animals they eat, how can we be so certain that simply supplementing a few vitamins found in animal products is a sufficient replacement? We hardly understand human metabolism at its most basic level, it's quite a stretch to think that we've cracked the code on the "essential" nutrients we would have received from consuming animals.

[aziaziazi]

> The commenter I responded to said that people don't need to eat animal products to live at optimal health, which is laughable

That is still technically incorrect and is refuted by observing healthy old vegans that consume supplements from cultivated-bacteria only for decades.

Those bacteria also develop in some animals digestive system as you already know, and eating those animals has been for a long time our main source of b12. The other (minor but non trivial) one has been non-washed fruits and plants human consumed during millennia, and that’s still how grazing animals ingest a bit everyday. The non grazing animals are widely supplemented with cultivated-b12. We’re producing around 80T/year for that which isn’t much we animals only need around 10mg/year. I'm not discussing the "non-natural" qualification of supplementation, just the fact it's today a very white practice to live an healthy (human or non human animal) life by ingesting only bacteria sourced B12.

> we've cracked the code on the "essential" nutrients

Yes we did, and the last of that nutrient has precisely been vitamin b12 which led to two Nobel prizes : https://pubmed.ncbi.nlm.nih.gov/23183296/

[doctordemen]

> the last of that nutrient has precisely been vitamin b12

What makes you so confident that this is the "last"?

[ada1981]

Thanks for this.

[chneu]

>The commenter I responded to said that people don't need to eat animal products to live at optimal health, which is laughable, and this is an incredibly clear example of why. A quick google search will illuminate the dangers of B12 deficiency.

Supplementing b-12 is easy. Getting it from natural vegan sources isn't hard.

It's wild the things people choose to believe about veganism or dieting in general.

You're either making wild assumptions or you've read some real sketchy stuff about dieting. Either way what you said isn't true and you seem to be repeating Joe Rogan type stuff about vegan diets.

[doctordemen]

> You're either making wild assumptions or you've read some real sketchy stuff about dieting. Either way what you said isn't true and you seem to be repeating Joe Rogan type stuff about vegan diets.

Huh?

> Supplementing b-12 is easy. Getting it from natural vegan sources isn't hard.

Citation needed.

[chneu]

You're making claims to begin with. Please cite your sources on B-12 and the other claims you've made. You're saying things that smell of bias. It also appears you're ignoring evidence that contradicts what you're saying, or at least choosing to not take it seriously.

I've been vegan for years. This stuff aint hard. The way people talk about vegan diets is wild. Vegan b-12 is easy to get, lol. Next you're going to claim that it's impossible to eat enough protein on a vegan diet, lol.

The way you speak about diets and vegan stuff smells very heavily of "bro beef pseudoscience" that's popular in the Joe Rogain type circles. I wouldn't be surprised if you claim the carnivore diet is the peak human diet. That's what I mean. You're repeating things that are not difficult to prove wrong with an air of superiority. It comes off as very "I know stuff you do not" which is very prevalent in the Joe Rogain circles.

[doctordemen]

> It also appears you're ignoring evidence that contradicts what you're saying, or at least choosing to not take it seriously.

Do comments on HN count as "evidence" to you?

> You're repeating things that are not difficult to prove wrong with an air of superiority.

I guess we're cut from the same cloth then.

Please drop the ad hominems, they do not serve to strengthen your argument. I have no idea what Joe Rogan circles talk about, eat beef at most 1x per month, and despise those who would reduce every discussion to culture war.

I'm asking a simple question, for my education. Can you provide a citation or any information about natural vegan B-12 sources? I haven't found anything, except that all vegan organizations recommend supplementing vegan diets with industrially synthesized B-12.

[const_cast]

> I haven't found anything, except that all vegan organizations recommend supplementing vegan diets with industrially synthesized B-12.

For those of us who are particularly frightened by fallacies of nature, have no fear: we already do this with a ton of nutrients and have for a long time. Iodine being the most obvious example. But almost every piece of food you can buy is going to be enriched in some way, even things like soda!