The B12 Debate

[urbpan]

I just found some more information about vitamin B12. (For those of you just tuning in, my nutrition professor explained that there are no non-animal sources of vitamin B12, causing controversy. I brought it up here, and there was more controversy [sort of])

The only reliable unfortified sources of vitamin B12 are meat, dairy products and eggs. There has been considerable research into possible plant food sources of B12. Fermented soya products, seaweeds and algae have all been proposed as possible sources of B12. However, analysis of fermented soya products, including tempeh, miso, shoyu and tamari, found no significant B12.

Spirulina, an algae available as a dietary supplement in tablet form, and nori, a seaweed, have both appeared to contain significant amounts of B12 after analysis. However, it is thought that this is due to the presence of compounds structurally similar to B12, known as B12 analogues. These cannot be utilised to satisfy dietary needs. Assay methods used to detect B12 are unable to differentiate between B12 and it's analogues, Analysis of possible B12 sources may give false positive results due to the presence of these analogues.

Researchers have suggested that supposed B12 supplements such as spirulina may in fact increase the risk of B12 deficiency disease, as the B12 analogues can compete with B12 and inhibit metabolism.

The current nutritional consensus is that no plant foods can be relied on as a safe source of vitamin B12.

This package of pro-meat propaganda comes from http://www.vegsoc.org/info/b12.html
that is, The Vegetarian Society. I can't find for sure whether "vegetarian source" B12 supplements are for real, or if they are "B12 analogues." The fact sheet goes on to say that Iranian vegans studied were found to obtain adequate B12 through vegetables contaminated with human feces.

Comments

[richmackin.livejournal.com]

Was it vegan feces?

[wakarusa.livejournal.com]

I feel kind of the same way about both spirulina and feces. not quite, though.

[urbpan.livejournal.com]

At least odwalla only puts spirulina in its drinks...

The supplements are not from animals.

[(Anonymous)]

It's true, B12 is not produced by plants. It's produced by bacteria. Which is why organic, not obsessively cleaned vegetables can sometimes provide B12.

The "vegetarian" supplements that I take are derived from the bacteria directly, and haven't been taken from an animal. So, while it's not technically plant-only, it's not animal either. (Bacteria fall into another kingdom, right?)

Oh, and spirulina turns my poop a lovely shade of bright green!

-Turtle

[wakarusa.livejournal.com]

we HOPE

A gross questionut does anyone have a real answer?

[(Anonymous)]

I'll preface this by stating that I'm presently a omnivore, so really this is academic for me. If the B-12 only comes from animal sources, does it stand to reason that you would get a richer grade of B-12 from carnivorous animal poop, or would the unwashed vegetation result in similar amounts of B-12 regardless? I suppose all this means is that if you're avoiding animal products for ethical reasons, there's no reason you couldn't just chomp on a handful of fewmets or whatever for your B-12. Not that I'm encouraging that sort of behavior.
-Andy

Re: The supplements are not from animals.

[urbpan.livejournal.com]

The "vegetarian" supplements that I take are derived from the bacteria directly.

This is the information I was looking for when I came across the stuff excerpted above. You will notice that there is no mention of it there (there is some mention of bacteria producing it, in the lower intestine, but nothing about how and if veggie supplements derive their B12).

What I need to see, is a statement to the effect of "Vegetarian B12 supplements are derived from the bacterium, [insert bacterium's latin name here] which is cultured in captivity/ centrifuged from otter scat/ whatever.

I suspect that the bacterium in question is our friend Spirulina spp. who goes around town getting called "blue-green algae" but who we know is a cyanobacterium.

Can you check around?

It's grown on rice.

[(Anonymous)]

I called VegLife, the makers of a vegetarian B12 supplement, and they say that the bacteria are cultured on brown rice. The bacterium is Cobalamin, according to my own vitamin container (Harvest Coop/store brand multi vitimins).

Though I did find an article that said that one study indicates that nori might actually provide B12 after all (but not those other kinds of seaweed or fermented foods). I think the jury is still pretty much undecided at this point. Once strict vegetarianism gets more popular, there will likely me more studies...

-Turtle

Re: It's grown on rice.

[urbpan.livejournal.com]

This is good to know--One thing, though: Cobalamin is just another name for B12.

After some more digging, I found that the bacterium used is Streptomyces sp.

I'm at a loss as to why this is conspicuously omitted from the Vegetarian Society's information on the subject.

Thanks for keeping up with it, Turtle!

Re: A gross questionut does anyone have a real answer?

[urbpan.livejournal.com]

One reason some people are vegan is to avoid any exploitation of animals--even animal products not derived from or resulting in slaughter are eschewed (wool, for example.) Thus, using animal feces as a source of B12 would still be non-vegan.

If you are going to do this, I recommend rabbit scat. It's small enough to take like a pill, and probably one of the safer poops to eat. Heck, rabbits even eat their own poop (to digest tough plant matter.)