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Amino Acids
DESCRIPTION
Amino acids are constituents of protein. They are composed
of carbon, hydrogen, oxygen, nitrogen and sometimes Sulphur .
From the different combinations and patterns of the 20 amino
acids derived from the diet, it is possible to make as many
as 100,000 different proteins in the body. We require these
proteins for growth and development, as well as for the synthesis
of hormones and enzymes. Protein is also essential to our
physical development.
Amino acids can be "ESSENTIAL"
or "NON-ESSENTIAL"
Certain amino acids are
known as "essential" because they are just that
- essential in our diets. That is, we cannot make them in
our bodies, so we must obtain them from food. High biological
value protein foods which contain all eight essential amino
acids are meat, fish, poultry, eggs and soya beans.
The eight essential amino
acids are: leucine, isoleucine, valine, lysine,
methionine, L-phenylalanine,
tryptophan and threonine. (On food supplement labels of amino
acids the ‘L’ denotes natural form, and the ‘D’
denotes synthesized - the opposite applies to Vitamin
E !).
There are two semi-essential
amino acids: arginine and histidine. These are known as semi-essential
because they are necessary during the growing phase of the
human body from childhood to adulthood.
Non-essential amino acids
do not have to be obtained through diet. The body is capable
of creating these from the essential amino acids, vitamins
and minerals in the body.
SUPPLEMENTAL USES
During general sports training
ie: swimming, running, cycling etc. an amino acid complex
may be valuable to someone looking for an additional fat-free
source of amino acids which are readily converted into body
proteins.
Health and growth of hair
requires adequate cysteine.
Methionine is also needed for production of Lecithin, in the
liver.
L - phenylalanine helps produce brain chemical indicating
a sense of 'fullness'. Mood elevator, by stimulating brain
activity, memory and alertness. Synergistic nutrients are
Vitamin B6 and Vitamin C .
Increasing mental alertness - tyrosine may be considered to
help reduce Anxiety and Depression associated with Stress.
Also, alertness and memory. Tyrosine supplements should not
be taken by those with high blood pressure.
Lysine as an essential amino acid is needed for the formation
of the non-essential amino acid carnitine. Wheat, rice, oat
and sesame protein are low in lysine, which means that some
diets especially vegan and vegetarian, can often be deficient
in this amino acid. This amino acid is also involved in collagen
formation (with Vitamin C ). Low levels of lysine can increase
Calcium loss in urine. Cold sores may be worse in people who
have an inadequate lysine intake. Arginine can exacerbate
cold sores and should be avoided by those with this condition.
Foods containing arginine - nuts, chocolate, cheese and peas
should be reduced as well.
Glutamine provides the brain with a usable energy source,
it crosses the blood-brain-barrier. Helpful in healing peptic
Ulcers. Needs adequate B6 for proper metabolism. Needed with
Chromium for GTF production.
SUGGESTED INTAKES
Amino Acid Complexes
An amino acid complex is a blend of essential and non-essential
amino acids. It is suitable for most people to take and is
usually derived from a dairy source. It may be useful immediately
before or after exercise or training to provide amino acids
necessary for cell division and regeneration, especially useful
for mending damage to muscles and connective tissue.
SAFETY
Individual amino acids are
best taken on an empty stomach, unless the pack states otherwise.
Amino acid supplements are usually available as 'free form'
or 'peptides', these are both preferable as they are pre-digested
(broken down) forms and easily absorbed into the bloodstream.
'Free form' means that the amino acids are in a single state
and 'peptide' means that only two are joined together.
It is considered prudent
not to advise 'individual' amino acid supplements to pregnant
women or children. Protein for both these groups is best derived
from food, so that an imbalance of amino acids is less likely
to occur. Teenage boys who are thinking of body building are
also well advised to stay away from growth-promoting individual
amino acid supplements. Physical training and good diet are
more beneficial to their development.
INTERACTIONS
& CONTRA-INDICATIONS
These vary according to
the individual amino acid being taken as a supplement. (Refer
to pages on individual amino acids - see index page).
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