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Artigo muito interessante de autoria da
Dra. Gina Shaw. Fonte. http://www.vibrancy.homestead.com/B12.html ------------------------------------------------------------------------------------- |
THE VITAMIN B12 ISSUE by Dr
Gina Shaw, D.Sc, M.A., Dip NH, AIYS (Dip. Irid.)
The
subject of vitamin B12 is not new to most vegans, vegetarians or raw
fooders. The supplement companies have many people running to
their
local health (drug) stores in an effort to make themselves
deficiency-free, but is this a good idea? A number of issues will
be
raised in this article and I will attempt to piece together some
information from many different and reliable (non-financially-oriented)
sources.
A
vitamin B12 deficiency is a serious disorder and indications of a
deficiency of vitamin B12, when they do reach a stage where they have
shown up, can be quite severe. Fatigue, paleness, anorexia,
mental
confusion, delusions, paranoia, weight loss, respiratory problems, etc.
are just some indications that a person may have a
B12-deficiency. In
my opinion, ME is often a B12-deficiency disorder. If you do
think you
may have a B12-deficiency, it would be wise for you to seek the advice
of a health practitioner (such as myself) who is knowledgeable about
B12-deficiencies, for immediate advice. I would strongly
recommend
that you do something to remedy the situation, as this deficiency can
eventually lead to death if left unchecked.
UK
official recommendations have decreased in recent years, the body's
needs having been previously over-estimated. Indeed, the Department of
Health recognises that some people have lower than average requirements
of B12. A whole lifetime's requirement of B12 add up to a 40 milligram
speck of red crystals, about one-seventh the size of an average tablet
of aspirin!
Vitamin
B12 is excreted in the bile and is effectively reabsorbed. This is
known as enterohepatic circulation. The amount of B12 excreted in the
bile can vary from 1 to 10ug (micrograms) a day. People on diets low in
B12, including vegans and some vegetarians, may be obtaining more B12
from reabsorption than from dietary sources. Reabsorption is the reason
it can take over 20 years for a deficiency disease to develop. In
comparison, if B12 deficiency is due to a failure in absorption, it can
take only three years for a deficiency disease to occur. Since vitamin
B12 is recycled in a healthy body, in principle, internal B12 synthesis
could fulfil our needs without any B12 being provided in the diet, but
there are other factors to be taken into consideration such as whether
there is sufficient cobalt, calcium and protein in our diet to ensure a
stable vitamin B2 level and the condition of our intestines.
Among
the many controversies surrounding vitamin B12, there is the argument
that, although Intrinsic Factor is produced in our stomachs and that
our intestines are known to produce vitamin B12, the bacteria is
produced too low down in the intestines and cannot be absorbed by our
bodies. This argument is still hanging around, however, according to Dr
Vetrano it was disproved by research over 20 years ago and is nothing
more than an obsolete scientific theory. Indeed, in a 1999
version of
'Human Anatomy and Physiology' by Marieb, it states quite clearly that
we do indeed absorb vitamin B12 through our intestines.
Many
people say that the only foods which contain vitamin B12 are
animal-derived foods. This also is untrue. No foods
naturally contain
vitamin B12 - neither animal or plant foods. Vitamin B12 is a
microbe
- a bacteria - it is produced by microorgannisms. Vitamin B12 is the
only vitamin that contains a trace element - cobalt - which gives this
vitamin its chemical name - cobalamin - which is at the centre of its
molecular structure. Humans and all vertebrates require cobalt,
although it is assimilated only in the form of vitamin B12.
B12
synthesis is known to occur naturally in the human small intestine (in
the ileum), which is the primary site of B12 absorption. As long
as
gut bacteria have cobalt and certain other nutrients, they produce
vitamin B12. Dr Michael Klaper argues that vitamin B12 is present in
the mouth as well and intestines. Furthermore, Dr Virginia
Vetrano
states that active Vitamin B12 coenzymes are found in bacteria in the
mouth, around the teeth, in the nasopharynx, around the tonsils and in
the tonsilar crypts, in the folds at the base of the
tongue, and in
the upper bronchial tree. Absorption of the natural B12 coenzymes
can
take place in the mouth, throat, oesophagus, bronchial tubes and
even
in the upper small intestines, as well as all along the
intestinal
tract. This does not involve the complex enzyme mechanism for
absorption (Intrinsic Factor) in the small intestine as required by
cyanocobalamin. The coenzymes are absorbed by diffusion from
mucous
membranes (11).
External
B12 coming into the body must be combined with a mucoprotein enzyme
named Intrinsic Factor, which is normally present in gastric
secretions, to be properly assimilated. If the Intrinsic Factor
is
impaired or absent, B12 synthesis will not take place, no matter how
much is present in the diet. A B12 deficiency can be
caused by
antibiotics (from the drugs themselves and contained in milk and meat),
alcohol (alcohol damages the liver, so drinkers need more B12) and
smoking (and all high temp cooked food is smoky) and stress also raises
B12 needs).
Many
nutritional analyses of foodstuffs were carried out such a long time
ago, and, as such, have not taken account of more up-to-date
technology. According to Dr Vetrano, current books on nutrition
in the
U.S. now state that there is B12 in any food that contains quantities
of the B vitamin complex, but previously they were just not able to
assay the amounts. Nowadays, more modern technology has allowed
them
to discover that there is B12 in those foods rich in the B complex.
The
author does not believe that a vitamin B12 deficiency is more
widespread in vegans or vegetarians - this is probably just another
marketing lie! In fact, many so-called studies 'showing vegans
deficient' have to be carefully studied themselves - many of them do
not prove vegans to be deficient at all! In fact, contrary to
meat and
dairy industry propaganda, meat-eaters are known to be more likely to
have a vitamin B12 deficiency - this has been known since
1959!!(1)
Having
said this, we must bear in mind that many vegetarians and vegans still
take antibiotics or consume antibiotic-containing foods such as onions,
garlic, strong radishes and other foods rich in mustard oil, which are
lethal to intestinal flora. The trouble is that once we have
damaged
our intestinal flora, it is difficult to correct without proper and
knowledgeable healthcare and dietary advice. It is of far
greater
importance to correct intestinal flora problems than to spend our lives
relying on so-called supplements. People who have a physical problem
because they think they are not getting enough vitamin B12, are in fact
often not digesting, absorbing or assimilating their foods properly
because of the condition of their gastrointestinal tract. When
their
intestines are healed, vitamin B12 can be utilized and produced once
again
Indeed,
Dr Vetrano argues that the real problem in so-called B12
deficiency is
a failure of digestion and absorption of foods, rather than a
deficiency of the vitamin itself. She further argues that
vitamin
B12 coenzymes are found in nuts and seeds as well as in many common
greens, fruits, and many vegetables. If we ate 100 grams of green
beans, beets, carrots, and peas we would have half of our
so-called
daily minimum requirement of Vitamin B12 coenzymes providing our
digestion and absorption are normal. From Rodale's The Complete
Book
of Vitamins, page 236 we find the following clarification:
"As you
know, the B complex of vitamins is called a 'complex'
because,
instead of being one vitamin, it has turned out to be a large
number
of related vitamins, which appear generally in the same foods." (11)
The
cause of malabsorption is commonly a gastrointestinal disorder and this
was known by pathologists way back in the l800s. In this case, one's
lifestyle must be assessed and brought into unison with the needs of
the living organism.
According
to Marieb's 'Human Anatomy and Physiology', vitamin B12 can be
destroyed by highly alkaline and highly acid conditions. This
assumes
that the B12 in meat would be easily destroyed because the hydrochloric
acid in our stomachs during the digestion of meat is highly acidic.
This may explain why meat-eaters are just as likely to have a B12
deficiency as vegans - even though their diet contains vitamin
B12.
Also, as mentioned earlier, another problem for meat-eaters is that
there are normally antiobiotics in meat plus the fact that many
meat-eaters destroy their friendly bacteria in their intestines by
constant putrefaction and the putrefactive bacteria naturally present
in meat will give the body a hard time. So, the damaged
intestines may
not function well enough to enable adequate vitamin B12 levels to be
asborbed.
Another
side to the equation is that low serum B12 levels do not necessarily
equate to a B12 deficiency necessarily. Just because there is a low
level of B12 in the bloodstream, this does not mean that there is a
deficiency in the body as a whole, it may well be being utilised by the
living cells (such as the central nervous system). More reliable tests
appear to be that of homocysteine levels and Methyl Malonic Acid tests.
Commercially,
vitamin B12 tablets are made from bacteria and the bacteria is deeply
fermented. A B12 supplement or injection may help in the
short-term,
should the levels fall low, but in the medium to long-term, I would
recommend a B12-deficient person tries to get to the bottom of why they
are continually becoming deficient, with the help of a Natural
Hygienist.
According
to Dr. John Potter PhD, of Fred Hutchinson Cancer Center, Seattle,
"Food's magic is based on thousands of complex interactions of dozens
of different phytochemicals which are difficult to recreate in pills.
While 190 solid studies prove that fruit and vegetables benefit,
supplements have only a smattering of evidence". Vitamins,
minerals,
hormones, etc. do not work in isolation, they work symbiotically.
They
work with other nutrients in order for their work to be carried
out.
When these highly complex substances are disturbed, their overall
effectiveness can be reduced. However, too much of a nutrient is
draining on our vital energy as the human (or non-human) organism may
have to expel a nutrient overload. Also, it is doubtful whether,
even
if you do have a B12 deficiency, you have only a B12 deficiency.
A
healthier diet and living conditions, as well as a fast may be in
order.
On
the topic of supplements in general, Dr Douglas Graham, in his book
'Nutrition and Athletic Performance', argues that supplementation has
proven to be an inadequate and incomplete method of supplying nutrients
as scientists cannot match nature's refined balances. He says
that
since an estimated ninety per cent of all nutrients are as yet
undiscovered, why would we want to start adding nutrients into our diet
one at a time rather than eating whole foods? Most nutrients are
known
to interact symbiotically with at least eight other nutrients and
considering this, the odds of healthfully supplying any nutrients in
its necessary component package becomes 'infinitesimally minute'.
More
to the point he adds, 'there has never been a successful attempt to
keep an animal or human healthy, or even alive, on a diet composed
strictly of nutritional supplements'. So I would say that a
reliance
on supplements, without getting to the root of the problem isn't ideal.
Dan
Reeter, at Bio-Systems Laboratories in Colorado is creating one of the
world's most comprehensive computer facilities for soil biology
testing. He says that, from his extensive tests, plants grown in
organically-managed soil make significantly higher levels of usable
vitamin B12. It has also been reported that vitamin B12 is
present in
wild fruits and wild and home-grown plant foods.
The
author contends that animal and dairy produce is a poor source of
Vitamin B12 since they are normally cooked and thereore the vitamin is
contained in nutrient-deranged foodstuffs which will inevitably destroy
the usability of the vitamin. Studies show that those following a
typical animal-based diet require more vitamin B12 than those who do
not. This is because the typical diet leads to digestive
atrophy.
Because B12 is peptide-bound in animal products and must be
enzymatically cleaved from the peptide bonds to be absorbed, a weakened
gastric acid and gastric enzyme secretions (due to a cooked food diet)
causes an inability to efficiently extract vitamin B12 from external
food. Nevertheless, raw food vegans can actually get more B12 by
reabsorption from bile than they do from external food. Wolfe argues
that the natural soil microbes and bacteria found on wild plant foods
and unwashed garden plants are typically adequate to supply our B12
requirements. The natural microbes in the soil need to be duplicated
and to colonise in our digestive tract, without fermentation or
putrefaction.
Another
point worth considering is that vitamin B12 Recommended Daily
Allowances (RDA's) are based upon the average cooked food (meat and two
veg), smoking, drinking person. Commercial interests have indeed
grossly exaggerated our needs for many nutrients. These studies tell us
nothing of the requirements for a healthy vegetarian. It is very
difficult to determine precise individual needs of any vitamin or
nutrient, and an overload of any vitamin or other nutrient creates an
unnecessary burden on our vital domain. Factors such as rate of
metabolism, stress, etc. can determine our differing and often changing
needs. Dr Victor Herbert reported in the American Journal of
Clinical
Nutrition (1998, Volume 48) that only 0.00000035 ounces (1 microgram)
of vitamin B12 is required per day. These minimum vitamin
requirements
may be inadequate to explain the needs of a healthy raw food vegan, for
example, who may require less B12 due to an improved gastric ability
and a high ability to recycle vitamin B12. (Cooking destroys
microbes
and a highly sterilised, cooked vegan diet may not provide the
intestines with enough good quality flora). Absorption rates of B12 are
inevitably higher in healthy individuals than in unhealthy
individuals. Studies, based on healthy Indian vegetarian
villagers,
showed that none of them exhibited symptoms of B12 deficiency, despite
levels of .3-.5 micrograms of B12.
I
believe that Vitamin B12 deficiency is typically caused by lack of
absorption in the intestinal tract rather than a lack of this vitamin
in the diet. Annie and Dr David Jubb argue that people have lived
in
such a sterile, antiseptic environment for so long that these necessary
symbiotic organisms have been less than present in our diet. They
argue that by ingesting soil-born organisms you can maintain an
enormous reservoir of uncoded antibodies ready to transform specific
pathogens, the way nature intended - by eating a little dirt!
If
a person is healthy and on a healthy vegan, high-percentage raw food
diet and does not habitually over-eat, wrongly combine their foods and
abuse their bodies generally, and is able to obtain quality produce and
utilise fasting quite regularly I would suggest that t is unlikely that
they will develop B12 deficiency symptoms providing their intestinal
flora was not previously deranged. Vitamin B12 deficiency is
usually
symptomatic of a larger problem i.e. poor intestinal flora, poor
absorption, gastric disorders , etc. and can also be attrributed to a
lack of sunlight. There are indeed many factors involved here
since
adequate B12 levels, as mentioned, are dependent upon sufficient
calcium, vitamin B12, zinc, cobalt, protein, etc.
I
would also suggest that just because a wild fruit or organic plant food
contains only a small amount, this does not mean it is deficient.
It
may just be because we only need a small amount anyhow. The pill
pushers are quick to say that our soil is deficient, but according to
Diamond and others, if a seed does not receive the elements it needs IT
WILL NOT GROW (OR WILL GROW POORLY - author). Also, plants obtain
nutrients from other sources in greater amounts: the sun, water and the
air. Plants actually obtain only about 1% of nutrients from the
soil.
If
you do develop a B12 deficiency, certain urgent dietary adjustments may
need to be made, and there is a possibility that fasting is in
order.
In any case, on switching to a healthier diet, be it vegetarian, vegan
or raw food (for optimum health), we should go back to nature as much
as possible and pay little attention to germ phobics who advise us to
scrub our vegetables and fruits. Buy organic and eat home-grown
or
wild foods and do not clean them too scrupulously! Also it is
important to ensure adequate nuts and seeds in the diet.
Please
note that it is not recommended for anyone to go on a fast of longer
duration than 1½ days without competent supervision, as
prolonged fasts
must be monitored by a qualified fasting supervisor.
Dr
Shaw is a Doctor of Science, her specialism being in Natural Hygiene
and Complementary Medicine and she is not a medical doctor She
is
available for health and nutritional consultations, fasting
supervision, courses in natural health, emotional healing and iris
analysis (iridology). Her email address is: [email protected] Visit
her
web site at http://vibrancy.homestead.com/pageone.html
1.
'Fit for Life', Diamond, H. and M., 1987
2.
'The Life Science Institute Course in Natural Health' - 1986
3.
'Nutrition and Athletic Performance', Dr D. Graham, 1999
4.
'Female Balance' article 2001 - www.living-foods.com
5.
Human Anatomy and Physiology - Marieb - 1999
6.
Correspondence with Dr Vetrano and family 2001
7.
'The Sunfood Diet Success Story' by David Wolfe
8.
B12 article by the Vegan Society
9 .
B12 article by the Vegetarian Society
10.
1990 'Solstice Magazine' article
11.
'Rethinking B12' article by Dr V. V. Vetrano
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