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Quest Vitamins LTD,
8 Venture Way,
Aston Science Park,
B7 4AP.

Tel: 0121 359 0056
Fax: 0121 359 0313
Registered in England No. 2530437

Amino Acids


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.


  • 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.


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.


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.


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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