Amazing Power of Amino Acids
In 1838, a Dutch chemist, G.J. Mulder, described a
certain organic material as "unquestionably the most important of all
known substances in the organic kingdom. Without it, no life appears possible
on our planet. Through its means the chief phenomena of life are produced."
This complex nitrogen-bearing substance was called protein from the Greek word
meaning "take the first place." Protein in now a group name,
signifying the principal nitrogenous constituents of the protoplasm, of all
plant and animal tissues. Proteins are extremely complex organic compounds of
the elements carbon, hydrogen, oxygen, nitrogen, and, with some exceptions,
sulfur. Most proteins also contain phosphorous, and some specialized proteins
contain iron, iodine, copper and other inorganic elements. The presence of nitrogen
distinguishes proteins from carbohydrates and fats.
Proteins are thus vital substances, which form
important constituent of muscles, tissues, and the blood. Proteins supply the building
material for the body and make good the wear and tear of tissues. Several
substances concerned with vital life processes such as enzymes, which help in digestion
of food, are chiefly protein in nature. There are several varieties of protein.
Each type contains a specific number of "building blocks" known as
amino-acids. Before they can be absorbed by the body, all proteins must first
be broken down into amino-acids. When food stuffs are ingested, the nutrients
and amino-acids do not immediately diffuse into all the different tissues.
There are a series of biochemical reactions
in the digestive tract which collect these proteins, break
them down and then use them as needed. Any interference with the normal
digestive process causes in-complete protein digestion resulting in gas,
bloating etc. There are about 22 amino acids needed for the normal functioning
of the body. The body can manufacture many amino acids if it has no adequate
nitrogen source, but it cannot produce certain others in sufficient amounts to
meet its needs. The amino acids that the body cannot synthesis is in adequate
amounts are called essential or indispensable because they must be supplied by
the diet in proper proportions and amounts to meet the requirements for maintenance
of growth of non-essential or dispensable amino acids are those that issue the body
can synthesize in sufficient amounts to meet its needs if the total amount of
nitrogen
supplied by protein is adequate. The essential and
non-essential amino acids are listed in table A.
TABLE A
Classification of
Amino Acids with respect to their essentiality
Essential
Histidine*
Isoleucine
Leucine
Lysine
Methionine
Phenylalanine
Theronine
Trypophan
Valine
Hydroxyproline
Proline
Serine
Tyrosine
Nonessential
Alanine
Arginine
Asparagine
Aspartic acid
Cysteine
Cystine
Glutamic acid
Glutamine
Glycine
It will be seen from this statement that nine amino
acids are essential for maintenance of nitrogen equilibrium in human bodies.
The estimated requirements of essential amino acids for infants, children and
adults are given in Table B. Men in the older age group appear to differ in their
requirements. Studies seem to suggest an increase need for methionine and
lysine for them. Infants and children have proportionally greater demands for
essential amino acids than adults. In addition, infants require histidine as an
essential amino acid.
Factors in addition to the age, sex and physiological
condition of an individual influence the requirements for specific amino acids.
If total protein intake is low, small surpluses of certain amino acids can
increase the need for others. The non-essential amino acids in protein also affect
the quality of protein. For example, the amount of sulfur - containing
essential amino acid methionine required may be somewhat reduced if cystine, a
sulfur-containing nonessential
amino acid, is supplied in the diet. Likewise, the
presence in the diet of tyrosine, a non-essential amino acid similar in
structure to phenylalanine, may reduce the requirement for phenylalanine. Much
research has been done on amino acids in recent times and this has paved the
way for dramatic treatment and cure of different problems by their judicious
use. They are now dubbed as "the nutrients of the 80’s" and
"medical foods". The various functions of the essential and
frequently investigated non-essential amino acids, their deficiency symptoms
and their therapeutic uses are discussed below:
TRYPTOPHAN
Of all the essential amino acids, tryptophan is the
one that is most investigated by nutrition researchers. It is essential to
blood clotting, digestive juices and the optic system. It induces sleep and
quietens the nervous system. It wards off signs of premature old age -
cataracts of the eyes, baldness, deterioration of sex glands and malformation
of teeth enamel. It is also necessary to the female reproductive organs and for
proper use of vitamin A by the body. Major sources for these amino acids are
nuts, and most vegetables. Lack of tryptophan causes
symptoms similar to those of vitamin A deficiency. A
number of scientists feel that it can be used as a safe and effective food remedy
for insomnia and pain. Under experimental conditions, tryptophan in doses of
one gram or more has been shown to be most effective for persons who suffer
from mild insomnia and for those who take a long time to fall asleep.
Tryptophan may also be a natural painkiller. Researches at Temple University
in Philadelphia
have indicated that it worked without causing the side effects associated with
other anesthesia or analgesics. Tryptophan as a food medicine should be taken
between meals with a low protein food such as fruit juice or bread. One to
three grams a day seems to be the range favored by most researchers.
METHIONINE
This is a vital sulfur-bearing compound which helps
dissolve cholesterol and assimilates fat. It is required by hemoglobin, the
pancreas , the lymph and the spleen. It is necessary to maintain normal body
weight and also helps maintain the proper nitrogen balance in the body. Rich sources
of methionine are Brazil nut, Hazel nut, and other nuts. It is also found in
Brussel sprouts, cabbage, cauliflower, pineapples and apples. Its deficiency
can lead to chronic rheumatic fever in children, hardening of the liver
(cirrhosis) and nephritis of the kidneys. Studies show that methionine and
chorine prevent tumors and proliferation.
LYSINE
Lysine inhibits viruses. Its use along with vitamin
C, zinc and vitamin A helps eliminate virus infections. Vitamin C protects this
amino acid while in the body so that lysine plus vitamin C has a much stronger
anti-virus effect than if either is used separately. Lysine also influences the
female reproductive cycle. Lack of adequate lysine in the diet may cause
headaches, dizziness, nausea and incipient anemia. The main sources of this
amino acid are most kinds of nuts, seeds, vegetables and sub-acid fruits. Lysine upsets
in the body have also been associated with pneumonia, nephrosis and acidosis as
well as malnutrition and rickets in children. It is considered a natural remedy
for cold, sores, shingles and genital herpes. In a study published in 1983, a group
of researchers polled over 1,500 people whose daily intake of lysine was over
900 mg. 88 % said that lysine seemed to reduce the severity of their attacks of
herpes virus and accelerated the healing time. These results have, however,
been disputes by some scientists.
VALINE
Valine is an essential body growth factor,
particularly for mammary glands and ovaries. Valine is directly linked with the
nervous system. It is essential for the prevention of nervous and digestive disorders.
Major sources are almonds, apples and most vegetables. Lack of this amino acid makes
a person sensitive to touch and sound.
ISOLEUCINE
This amino acid is essential for maintaining the
nitrogen balance vital to all body functions. It also regulates metabolism of
the thymus, spleen and pituitary glands. Rich sources are sunflower seeds, all
nuts, except cashew nuts, avocados and olives.
LEUCINE
It is the compliment of isoleucine, with a similar
chemical composition although in different arrangement. Its functions and
sources are also similar.
PHENYLALANINE
This is essential to the production of hormone
adrenaline; to the production of the thyroid secretion and the hair and skin
pigment, melanin. It is effective in weight control because of its effect on
the thyroid. Its use before meals suppresses the appetite substantially.
Patients taking half a teaspoon of the powder 30 minutes before each meal, lose
from a quarter to half a pound a day. It is also essential for the efficient
functioning of kidneys and bladder. Major source are nuts, seeds, carrots,
parsley and tomatoes. An important recently discovered therapeutic use of phenylalanine
is its ability to overcome most conditions of lethargy through stimulation of adrenaline.
THREONINE
This amino acid is found in various types of milk and
is a major constituent in cow’s milk. Other sources are nuts, seeds, carrots
and green vegetables. Without threonine, a child’s development will be
incomplete and there will be malfunctioning of the brain. This amino acid has a
powerful anti-convulsive effect.
HISTIDINE
This helps tissue growth and repair. It is active in
producing normal blood supply. It is also vital to the formation of glycogen in
the liver. It is found in the root vegetables and all green vegetables. Studies
indicate that the free form of histidine in the blood is low in cases of rheumatoid
arthritis and if taken orally, may possibly depress the symptoms of this
ailment. Oral histidine has , however, a tendency to stimulate hydrochloric
acid secretion in the stomach and persons who are susceptible to an
overabundance of acid and also those who have ulcers should avoid taking pure
histidine. Orthopaedic and joint pains are caused by lack of histidine.
ARGININE
This is called the "fatherhood" amino acid
as it comprises 80 per cent of all male reproductive cells. It is essential for
normal growth. Serious lack of this amino acid reduces the sex instinct causing
impotence. It is found in most vegetables, especially, green and root vegetables.
CYSTINE
It provides resistance by building up white-cell
activity. It is an indispensable amino acid. It is one of the mainstays of
health as it is essential for the proper formation of skin and helps one recover
from surgery. It promotes the formation of carolene which helps hair growth. It
is used in the treatment of skin diseases, for low white blood-cells counts and
for some cases of anemia.
TYROSINE
This can be called an anti-stress amino acid. Dr. Richard
Wurtman who recently conducted experiments on the use of this amino acid says:
"Supplemented tyrosine may be useful therapeutically in persons exposed
chronically to stress."
Tyrosine is also beneficial for depression,
nervousness, irritability and despondency. Research has established this amino
acid to be effective in the management and control of depression in conjunction
with glutamine, tryptophan, niacin and vitamin B6. It is also helpful in the
treatment of allergies and high blood pressure. Although individual nee may
vary, Dr. Wurtman considers 100 mg. per kilogram of body weight per day an
optional dose. This works out to about 5.4 grams of tyrosine a day for a person
weighing 120 pounds. The supplement may be divided into three separate doses
each day. When tyrosine is taken, a supplement of valine, another essential
amino acid should not be taken as valine may block tyrosine’s entry to the
brain.
GLUTAMINE
This little known non-essential amino acid known as
"sobriety nutrient" . It is considered beneficial in the treatment of
alcoholism. According to Roger J. Williams, a world-known nutritionist,
glutamine reduces the usually irresistible craving for alcohol that recovering
drinkers almost inevitably encounter.
CYSTEINE
There is some evidence that cysteine (not to be
confused with cystine) has certain therapeutic value as a nutritional
supplement. Dr. H. Ghadimi, chairman of the nutrition committee at Nassau country, (New
York ) medical centre uses cysteine supplements to
treat his patients suffering from obesity. He considers that there is link
between obesity and over-production of insulin and that cysteine supplements
taken along with vitamin C at the end of the meals somehow neutralizes some of
the excess insulin, which is responsible for fat production. He regards this amino
acid as ‘anti-cancer and anti-ageing’ and claims that like vitamin C, cysteine
protects the body from damage by oxidants. When one or more of the essential
amino acids are left out of the diet, symptoms similar to those of vitamin
deficiencies may be experienced such as low blood pressure, anemia, poor muscle
tone, slow healing of wounds, loss of weight, poor resistance to infections and
bloodshot eyes. Children who do not get the required amounts of amino acids in
their daily diet suffer from stunted growth and permanent damage to the glands.
On the other hand, those getting the full quota of amino acids in their diet
will be rewarded with vigor, vitality and long life. The best food proteins
with all the essential amino acids are found in almonds, cheese and eggs. Amino
acids are being increasingly and successfully used in the treatment of several
diseases, such as stomach ulcers, burns, kidney diseases and liver diseases. It
has also been observed that the diseases of old age can be largely prevented if
elderly persons obtain the proper food supplements of amino acids, vitamins and
minerals. Amino acids are needed at every stage from infancy to old age - to
repair worn out tissues and to create new ones.
Source: www.healthlibrary.com through
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