[prrls]

"Regular" people doesn't need in any way of to these B12 supplements, as there is plenty of it in animal products, which have already been taking B12 supplements all their lives. However, vegans need to take these supplements if they want their B12 intake, without animals as the intermediary.

As a side note: B12 is created by micro-organisms in the soil, making our vegetables and fruits completely covered of it. With our modern lifestyle, the soil is terribly poor of these micro-organisms and having cleaned-as-hell vegetables reduces even more the B12 we can find in these vegs.

[pmoriarty]

Not only that, but B12 isn't actually produced by any of the animals which make up those "animal products" which allegedly have "plenty" of B12 in them. The animals, if they have B12, get it from eating vegetables which have bacteria on them.

These days, however, many animals destined for the dinner table are pumped full of antibiotics (which may kill those B12-producing bacteria), are fed other animals or sterilized grains/vegetables. So it is quite possible that the animals themselves aren't getting adequate B12, and as a result even animal eaters might have a B12 deficiency.

My own doctor recommends all his patients, whether or not they're vegetarian, take B12 supplements.

[cpncrunch]

From wikipedia:

"Ruminants, such as cows and sheep, absorb B12 produced by bacteria in their guts"

[Raphmedia]

Fun fact: Rabbits eat their fecal pellets (they have soft and hard poops, pellets are the hard ones). Those are filled with half digested plant matter. Since they are exposed to bacteria during the first digestion, those fecal pellets are full of vitamins. B12 is one of them. They often eat those dried pellets directly from their fur as breakfast to get the energy to start the day.

[pmoriarty]

And how do the bacteria get there? Do they get there if they're fed sterilized food or other cows? And are the bacteria killed off by the antibiotics they're given?

[dualogy]

> And how do the bacteria get there?

Pre-seeded during breast feeding, as happens across all mammals. How many billions of years do you want to go back on this question?

> And are the bacteria killed off by the antibiotics they're given?

Evidently not, as in developed country sick animals don't get turned into meat foods on principle and by law --- so they don't show up deficient. If they lived for 9 decades like we do, they might (or not). But they don't.

[tgb]

But you can just measure whether animal eaters (tend to) have a B12 deficiency or not - you don't need to know any of this. Is your doctor recommending this based off a long chain of reasoning or based off of a study just directly measuring the rates of B12 deficiency? Since the latter is much easier and is what you actually care about.

[_0w8t]

It is interesting that B12 in sufficient quantities is actually made by bacteria in the gut, but as it is not absorbed there (only small intestine can absorb that) it became a waste. It is probably one of the reasons that animals like dogs or gorillas eat their feces.

[1] http://www.veganhealth.org/b12/animal

[prrls]

Thanks for the website you linked, I was searching for something like this for a while now.

[Raphmedia]

That is the reason rabbits will eat their fecal pellets.

[CWuestefeld]

My Crohn's disease impairs my ability to absorb nutrients, and so my doctor has instructed me to supplement several things, including B vitamins and calcium.

In the past he's given me prescriptions for these supplements, but these are vastly more expensive than the equivalent OTC versions (and yes, I've checked that it really is the equivalent molecule). So I'd hate to see new regulations that would increase my expenses just because some people believe in some kind of voodoo nutrition contrary to best practices.

[PeachPlum]

I'm a single data point in this story.

I've been vegan since 1991. I also have Crohn's disease.

I had a bowel resection in 2001 and subsequently my B12 blood tests revealed a deficiency. I was then prescribed a course of monthly B12 injections. These went down to 3 monthly and for the last 5 years my yearly blood test have deemed them unnecessary.

However, I now have Vitamin D deficiency instead. Plus ça change.

[hfourm]

Its worth noting that there are people who have b12 absorption deficiencies. My family has a history of it and a few are prescribed b12 injections once a month.

These injections are usually much higher than what you would take in pill for, as your body absorbs it easier and stores some for later.

Would be interested in more real science about the injections.

[jlebrech]

most factory farmed animals get their B12 from an injection

[mokkol]

Do you have a source of this?

[jlebrech]

http://www.farmhealthonline.com/disease-management/cattle-di...

https://www.riseofthevegan.com/blog/b12-is-not-just-a-vegan-...

here's what they give them:

https://www.alibaba.com/product-detail/supplements-for-anima...

https://www.norbrook.com/products/intravit-12-005wv-solution...