Since Methionine is the one essential amino acid often at lowest
levels in veg, particularly soy/tofu based diet, symtoms of Methionine
deficiency are good to know. 

Methionine deficiency
Methionine deficiency is caused by an abundance of the ß-chain of
ß-conglycinin, a seed storage protein that lacks methionine.
Methionine deficiency is associated with a deficiency of
S-adenosylmethionine which acts as an endogenous anti-depressant. Most
people consume plenty of methionine through a typical diet. Lower
intakes during pregnancy have been associated with neural tube defects
in newborns. Methionine deficiency (primarily in salmonids) leads to
reduced growth rate with the development of bilateral cataracts.
(Zinc, and cystine deficiencies can also cause cataracts) It is felt
that deficiencies of vitamin A and riboflavin also play a role in this
lesion. Methionine deficiency causes the liver to metabolize only
histidine to form, resulting in an incomplete form of folic acid.
Methionine deficiency can cause apathy, loss of pigmentation in hair,
edema, lethargy, liver damage, muscle loss, fat loss, skin lesions,
weakness, and slowed growth in children.


-------

More on Methionine 

Methionine, organic compound, one of the 20 amino acids commonly found
in animal proteins. Methionine is one of the several essential amino
acids needed in the diet; the human body cannot synthesize it from
simpler metabolites. Methionine supplies sulfur and other compounds
required by the body for normal metabolism and growth. It is an
important source of dietary sulfur. Methionine also belongs to a group
of compounds called lipotropics; others in this group include choline,
inositol, and betaine. Methionine is one of only two amino acids
encoded by just one codon (AUG) in the standard genetic code
(tryptophan, encoded by UGG, is the other). L-methionine is a
sulfur-containing amino acid that is minimally soluble in water. Its
sulfur is non reactive.
 
Methionine functions, uses, and health benefits
Methionine reacts with adenosine triphosphate to form S-adenosyl
methionine. S-adenosyl methionine is the principal methyl donor in the
body and contributes to the synthesis of many important substances,
including epinephrine and choline. SAMe is
involved in the synthesis of creatine, epinephrine, melatonin and the
polyamines spermine and spermidine, among several other substances.
Since methionine is the only essential amino acid not present in
significant amounts of soybeans, it is produced commercially as an
additive for soybean meal. Methionine is incorporated into the
N-terminal position of all proteins in eukaryotes and archaea.
Methionine plays a role in cysteine, carnitine and taurine synthesis
by the transsulfuration pathway, lecithin production, the synthesis of
phosphatidylcholine and other phospholipids.

Methionine in lipotropic combinations has been proposed for treating
endometriosis, a condition in which patches of endometrial tissue from
the uterine lining grow outside the uterus. Methionine is an
especially important nutrient beneficial for those suffering from
estrogen dominance, where the amount of estrogen in the body is
excessively high when compared to its opposing hormone called
progesterone. The nutrient is believed to help by expediting the
removal of excess estrogen from the liver.

Methionine is both an antioxidant and lipotrope, meaning it helps
remove fat from the liver. Methionine contributes to the
hydrophobicity of a protein. Methionine controls the level of
beneficial sulfur-containing compounds in the body. These
sulfur-containing compounds are in turn vital for defending against
toxic compounds like heavy metals in the liver. Methionine helps
reduce histamine levels, which are amino acids that control dilation
of blood vessels and influence brain function.
 
Dietary sources of methionine

Meat, fish, and dairy products are all excellent sources of
methionine. L-methionine is also found in fruits and vegetables, but
not as abundantly. Small amounts of free L-methionine occur in
vegetables, vegetable juices and fermented foods. Vegetarians can
obtain methionine from whole grains.
 
Methionine dosage, intake

Amino acid requirements vary according to body weight. L-methionine
supplements should only be taken with a physician's recommendation.
According to the Food and Agriculture Organization of the United
Nations (FAO) and World Health Organization (WHO), recommended daily
L-methionine intake is 13 mg per kg or about one gram daily for
adults. During methionine supplementation, intake of taurine,
cysteine, and other sulfur containing amino acids, as well as B6 and
folic acid should also be included.
 
 
Toxicity, side effects, interactions, and contraindications
Excessive methionine intake, together with inadequate intake of folic
acid, vitamin B6, and vitamin B12, can increase the conversion of
methionine to homocysteine. Homocysteine is a potentially harmful
blood fat that has been linked to atherosclerosis (hardening of the
arteries). L-methionine supplementation should be avoided by those
with neoplastic disease and elevated homocysteine levels and used with
caution in those with coronary heart disease. L-methionine supplements
should be avoided by pregnant women and nursing mothers unless they
are prescribed by a physician. There are no known drug or nutrient
interactions associated with methionine.





------------------------ Yahoo! Groups Sponsor --------------------~--> 
Get fast access to your favorite Yahoo! Groups. Make Yahoo! your home page
http://us.click.yahoo.com/dpRU5A/wUILAA/yQLSAA/JjtolB/TM
--------------------------------------------------------------------~-> 

To subscribe, send a message to:
[EMAIL PROTECTED]

Or go to: 
http://groups.yahoo.com/group/FairfieldLife/
and click 'Join This Group!' 
Yahoo! Groups Links

<*> To visit your group on the web, go to:
    http://groups.yahoo.com/group/FairfieldLife/

<*> To unsubscribe from this group, send an email to:
    [EMAIL PROTECTED]

<*> Your use of Yahoo! Groups is subject to:
    http://docs.yahoo.com/info/terms/
 



Reply via email to