Vitamin B12
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Size: 60 caps. Price: $8.95 |
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Vitamin B12
Vitamin B12 (cobalamin)
is an important water-soluble vitamin. In contrast to other
water-soluble vitamins it is not excreted quickly in the
urine, but rather accumulates and is stored in the liver,
kidney and other body tissues. As a result, a vitamin B12
deficiency may not manifest itself until after 5 or 6 years
of a diet supplying inadequate amounts.
Vitamin B12
functions as a methyl donor and works with folic acid in the
synthesis of DNA and red blood cells and is vitally
important in maintaining the health of the insulation sheath
(myelin sheath) that surrounds nerve cells. The classical
vitamin B12 deficiency disease is pernicious anaemia, a
serious disease characterized by large, immature red blood
cells. It is now clear though, that a vitamin B12 deficiency
can have serious consequences long before anaemia is evident.
A deficiency often manifests itself
first in the development of neurological dysfunction that is
almost indistinguishable from senile dementia and
Alzheimer's disease. There is little question that many
patients exhibiting symptoms of Alzheimer's actually suffer
from a vitamin B12 deficiency. Their symptoms are totally
reversible through effective supplementation.
A low level of
vitamin B12 has also been associated with asthma, depression,
AIDS, multiple sclerosis, tinnitus, diabetic neuropathy and
low sperm counts. Clearly, it is very important to maintain
adequate body stores of this crucial vitamin. The amount of
vitamin B12 actually needed by the body is very small,
probably only about 2 micrograms or 2 millionth of a gram/day.
Unfortunately, vitamin B12 is not absorbed very well so much
larger amounts need to be supplied through the diet or
supplementation. The richest dietary sources of vitamin B12
are liver, especially lamb's liver, and kidneys. Eggs,
cheese and some species of fish also supply small amounts,
but vegetables and fruits are very poor sources. Several
surveys have shown that most strict, long-term vegetarians
are vitamin B12 deficient. Many elderly people are also
deficient because their production of the intrinsic factor
needed to absorb the vitamin from the small intestine
decline rapidly with age. Fortunately, oral supplementation
with vitamin B12 is safe, efficient and inexpensive. Most
multi-vitamin pills contain 100-200 microgram of the
cyanocobalamin form of B-12.
This must be
converted to methylcobalamin or adenosylcobalamin before it
can be used by the body. The
actual absorption of B12 is also a problem with supplements.
Swallowing 500 micrograms of cyanocobalamin can result in
absorption of as little as 1.8 microgram so most
multivitamins do not provide an adequate daily intake. The
best approach is to dissolve a sublingual tablet of
methylcobalamin (1000 micrograms) under the tongue every day.
That will be sufficient to maintain adequate body stores.
However, if a deficiency is actually present then 2000
microgram/day for one month is recommended followed by 1000
microgram/day. Some physicians still maintain that monthly
injections of vitamin B12 is required to maintain adequate
levels in the elderly and in patients with a diagnosed
deficiency. There is however, no scientific evidence
supporting the notion that injections are more effective
than sublingual supplementation.
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Copyright ©
2006 muscle maximize™ All Rights Reserved These statements have not
been evaluated by the Food and Drug Administration. These
products are not intended to diagnose, treat, cure or prevent any
disease |
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