Vegetarianism, was Native nutrition FAQ?

[Guest guest]

At 03:43 PM 6/15/2002 +0000, you wrote:

>Meat's

>not technically necessary, but animal products are...and it just so

>happens that eggs and milk are a couple of the better ones. They

>provide plenty of fat, B-12, high quality protein, vitamin D, and pre-

>formed vitamin A. It may not be exactly *optimal*, but it's most

>definitely adequate to meet your needs if you consume enough to get

>all of your vitamin A,D, and B-12.

& others:

I've always has a question about the B-12 necessity and animal foods. What I've

read is something like the following:

(From: http://www.beyondveg.com/billings-t/comp-anat/comp-anat-7a.shtml):

" Vitamin B-12 is made only by bacteria; it is not synthesized by plants or

animals. The very limited (usually only trace) amount of B-12 in plants comes

from uptake of the vitamin from the soil, and from surface contamination with

B-12 producing bacteria. (This is discussed in detail below.) Animals

concentrate B-12 from the food they eat, and, in the case of folivores,

biologically active B-12 may be produced by bacteria in the fermenting chambers

in the digestive system. The end result of this is that plant foods provide

little (if any) B-12, and animal foods are the only reliable food sources for

B-12. "

Now, if B-12 is really from bacteria, then at least some of the " fermented

products " should contain B-12: and it does seem to be high on a lot of the

content lists for products like Kimchi or Kefir. (Though it's not clear to me

how much of the B-12 comes from the ingredients and how much from the bacteria:

Kimchi often contains raw fish). And the macrobiotic people do seem to eat a lot

of fermented products.

So when I hear things like " animal foods are the only reliable food sources for

B-12 " , (which is commonly said) it sounds a bit inaccurate to me, unless you

include bacteria as an " animal food " (which technically they are, since they

aren't plants, though they aren't as cute as a rabbit, and few people worry

about the ill-treatment of bacteria). Or is it the case that fermented foods

don't produce enough B-12, or produce it reliably enough?

It seems to me that a lot of cultures get a fair number of calories daily from

fermented products -- like the Hawaiians and poi -- , and the changes that occur

in vitamin content and bioavailability aren't taken into account to the extent

they should be. I'd guess that boiled Taro root and Poi would show up very

differently on that Excel chart. And that a lot of people who are healthily

vegetarian are really eating animal products in the form of bacteria?

-- Heidi

[Guest guest]

> So when I hear things like " animal foods are the only reliable

> food sources for B-12 " , (which is commonly said) it sounds a bit

> inaccurate to me, unless you include bacteria as an " animal food "

> (which technically they are, since they aren't plants, though they

> aren't as cute as a rabbit, and few people worry about the

> ill-treatment of bacteria). Or is it the case that fermented foods

> don't produce enough B-12, or produce it reliably enough?

I suspect there may be a few issues that bear on this.

(1) I don't think that all bacteria produce b-12.

(2) Of those that do, some apparently produce b-12 analogues

that are biologically useless to humans.

(3) I believe B-12 synthesis would require the presence of the

mineral cobalt in the substrate since cobalt is part of the

molecule.

(4) Concentrations of b-12 are low or unreliably variable in

non-animal sources.

(5) It's not entirely true that herbivores don't produce b-12

since the bacteria in their digestive tracts produce it.

I'd argue that those bacteria, in the case of a cow's rumen

for instance, are essentially part of the animal. Without

them, the animal would die because it couldn't properly

digest its food; so I don't see them as a separate entity.

I further suspect (pure speculation here) that herbivores may convert

some of the analogs that they consume and produce in their digestive

tracts to more biologically active forms. I recall reading for

instance, that we convert cobalamin to the even more active form,

methylcobalamin, in our bodies.

At any rate, even PCRM, the not-particularly-objective source of

health information as it relates to veganism, specifically states

that fermented foods, algae, and seaweeds are NOT reliable sources.

They pointedly recommend that vegans seek out a synthetic source such

as enriched cereals and soy milks. They also mention that Red Star

Vegetarian Support Formula yeast is a reliable source. That yeast is

grown on a synthetically b-12 enriched medium without which the yeast

would still be devoid of usable b-12.

When PCRM identifies a deficiency in vegetarian diets, and says that

there is no natural dietary way to reliably obtain adequate amounts,

I'd suggest that people would do well to heed their advice. They're

not going to say something like flippantly since it runs counter to

their entire philosophy and purpose for existence.

You can find their statement on B-12 here:

http://www.pcrm.org/health/Info_on_Veg_Diets/b12.html

> It seems to me that a lot of cultures get a fair number of calories

> daily from fermented products -- like the Hawaiians and poi -- ,

> and the changes that occur in vitamin content and bioavailability

> aren't taken into account to the extent they should be. I'd guess

> that boiled Taro root and Poi would show up very differently on

> that Excel chart. And that a lot of people who are healthily

> vegetarian are really eating animal products in the form of

> bacteria?

I don't know about poi, but I'd guess that it's subject to the same

problems as other fermented foods apparently are in that regard. I

question whether there are, in fact " a lot of people who are

healthily vegetarian. " Ovo-lacto, lacto, and pescetarian eaters

aren't *really* vegetarians. They're consuming animal

products...that's especially true for pescetarians and ovo-lacto.

Eggs and especially fish both contain very significant quantities of

b-12. Vegans can remain healthy for years, but I doubt there are

more than a handful (if that) of true vegans who don't use b-12

supplements who remain healthy for than a decade or who manage to

successfully produce healthy children after a similar amount of time.

....and that's without even going into Vitamin D, true vitamin A, DHA,

EPA, AA, bioavailable zinc, bioavailable iron or conditionally

essential animal-derived aminos. Am I forgetting anything? ;-)

I *do* believe that it's certainly possible for vegans to use

supplements to avoid b-12 deficiency, but I don't believe that's

sensible. If we need a nutrient, and it's poorly supplied or not

supplied at all outside of a certain class of foods, then we

biologically need that class of foods. How many other factors are

there in whole foods that we need that we don't yet know about? I'm

not willing to gamble that taking an isolated cocktail of chemicals

in a pill is going to meet my needs. If humans need animal-derived

nutrients, they should get them from animal foods.