On Sat, 20 Jan 2001 21:04:49 -0400, matesz <[log in to unmask]> wrote:
>>Joseph: .. We produce some B12 each day in our digestive system.
Don:
>True, but it is not usable because it is produced in the intestines, and to
>absorb it it has to first be attached to intrinsic factor, found only in
>the stomach. Hence, for humans to make use of the B12 produced in the
>intestines, the intestinal contents would have to back up into the stomach,
>then return down again into the small intestine. In humans, such
>regurgitation would be pathological, since the lower sphincter on the
>stomach is effectively designed to allow only one way traffic.
For the B12 to come in contact with the intrinsic factor (which is produced
in the stomach) the intrinsic factor simply has to move on to the intestine,
isn't it? In the Intestine it can combine with the B12 and at the end of the
intestine (the ileum) it is absorbed.
The intrinsic factor is necessary for the re-absorbation of the vitamin-b12
which enters into the intestine from the body anyway.
>Many Americans consume that amount of animal protein and fortified
>products,
>but studies are increasingly showing that Americans, especially elderly
>Americans, suffer from poor B12 status (not called deficiency, because it
>does not involve megaloblastic anemia), affecting nervous and circulatory
>systems, despite no lack of intrinsic factor (more on that below), but
>simply from inadequate intake, as shown by the fact that oral
>supplementation reverses the low status.
There are assumptions that "nowadays" more B12 is required for humans.
E.g. because of NO (nitric oxid) from the environment which may destroy some
of it. Or maybe a disturbed gut flora by Helicobacter pylori, see:
http://www.yourhealthbase.com/vitamin_B12.html
Or the requirement is so high (my own suggestion) because vitamin B12 can in
part replace annother vitamin, which is notoriously low in supply in
"modern" diets: folic acid.
Means: people are eating unnaturally few fresh raw vegetables (the natural
paleo source of folic acid) and therefore "need" very high amounts of
vitamin B12.
Joseph:
>> Third, in the U.S., 95% of all cases of B12 deficiency occur in
>> the "meat" eating population. Therefore, a lack of B12 in the
>> diet is not always the primary cause of B12 deficiency.
Don:
>... The important
>point here is this: meat eating is not the cause B12 deficiency, although
>the authors crafty draft suggests the opposite.
I would say, Joseph actually expressed it very right and clearly.
The real (main, only?) cause of a B12 deficiency is the lack of intrinsic
factor.
Not the missing B12 in the food. May it come from meat or the intestine or
from whatever source.
Vitamin b12 is *not* only produced by intestinal bacteria (of cows or
humans). There are bacteria living on the surface of plants, which produce
it (it is *only* produced from bacteria, not from cows).
So eating plants unwashed would also contribute to vitamin b12 intake,
wouldn't it?
One example is the "famous" algae spirulina which is said to have big
amounts of cobalamin (b12). From bacteria living on the algae's surface.
If the b12-amount from spirulina is right, then it the far far best source
of this vitamin.
It has been doubted that the spirulina cobalamin is actually biologically
active. I plan to do a self test on it:
The b12 supplementation i did made me somehow "dependant" on *very* high
doses of this stuff. If I don't get it, i feel consequences after 2 or 3
days. And I take really *huge* amounts. (100 ug last for the 2 or 3 days,
1000ug last for about 1 week).
This is far more as i could get from meat (100ug required 200lbs meat).
Now I am a test person.
I'll try to eat spirulina to see if the symptoms still arise.
>Since more than 95% of people are meat eaters anyway, it is hardly
>surprising that 95% of any particular disorder occurs among meat eaters.
>The accurate statistic to use here would be the relative incidence of
>reported B12 deficiency among meat eaters compared to the relative
>incidence
>of the deficiency among meat avoiders.
That's right. But if dietary input would actually be the cause
of vitamin b12 defficiency then it *should* show up really frequent amoung
people with are eating zero of it, right?
If about 1% of the *whole* population is vegan, the b12-defficiency should
should be a really frequent disease.
How many vegans are in the USA? 1 million? and how many cases of vitamin b12
deficiency? 100 per year?
Even among the (few) cases of B12 deficiency, vegan people don't show up
more frequent than ordinary meat eaters.
You try to explain the statistics with psychology or else.
I think the odds show that *the* cause for B12 deficiency is a lack of
intrinsic factor.
Zinc topic.
Joseph:
>> The
>> WHO recommendations for zinc are lower then the USA recommendation
>> because absorbability of zinc on such a diet is 30%, 10% higher then
>> on a typical US diet.
>
>This is totally wrong. The WHO standard is lower not because zinc is
>better absorbed from unrefined grains (in fact it is the opposite), ....
> The Nutrition Desk
>Reference (NDR) states: "Anywhere from 20 to 40 percent of the mineral
>[zinc] is absorbed from a mixed diet." Mixed means including meat; so
>where did they get the idea that a mixed diet provides only 20 percent
>absorption, but an unmixed diet provides better? None of my nutrition
>textbooks have mentioned anything of the sort.
The typical US "mixed" diet includes meat AND phytates, isn't it?
In "modern" diets like US,EUROPE... it is no longer common to properly
process grains by phytate-reducing techniques (like soaking).
Traditional diets employ phytin reducing techniques like sourdough and other
soaking and germinating techniques. (Have you ever tried south-indian idli?)
This may explain the better availability of zinc of unrefined grain eaters.
If they eat them in a traditionally proven way.
In addition grains have more zinc per weight (and therefore much more zinc
per kcal or protein).
100g beef has 3.8 mg zinc this is 0.19 mg per gram protein
100g millet has 4 mg zinc this is 0.74 mg per gram protein, 4 fold
100g wheat germ has 12 mg zinc
while 15mg is on my recommendation list.
People usually eat much more millet or wheat per day as meat.
(600g of wheat/millet compared to 250g meat average in germany)
Only heavy meat dieters (without grains) can overcome the zinc shortage of
conventional nutrition. Or traditional grain eaters.
>The Pritikin center advocates a high phytate, low meat, low B12, low zinc
>diet and yet claims it is B12 and zinc adequate, ....
I don't know about Pritkin, but what is high-phytate or not is determined
by the (traditional) processing methods.
While the total amount in whole seed diets is rather high.
> It is amazing to me how people can so readily believe that
>poverty diets are the solution to malnutrition.
A diet of 90% whole grains, a little milk and some 6% meat is not a poverty
diet, it is the diet of *culture*. These are the only kind of diets
since the emergence of agriculture (10000 years back) up to the upcome of
industry (150 years back).
Except the remaining hunter/gathering people
- but those who were remaining *after* agriculture were left to deserts.
regards
Amadeus
|
