Ever wondered whether amino acid supplements really work? We reveal some surprising facts...

FACT: Protein is made from amino acids. So it should follow that amino acid supplements can be combined in many different ways to form proteins in the body. In the same way as when you eat protein, it is broken down in your digestive system into its constituent amino acids and di-peptides (two amino acids attached to each other).

In this article we'll first we'll look at the facts, lay the ground work and build from there, so to speak. We'll look at whether amino acid supplements have a part to play in your bodybuilding protein diet or are just good for window dressing.

There are two varieties of amino acids, the first are called dispensable amino acids (DAAs) as these can be made in the body from other amino acids together with nitrogen and carbohydrate. These are:

Alanine

* Major component of connective tissue * Key component of the glucose alanine cycle which enables muscles and other tissues to derive energy from amino acids * Immune system builder

Arginine

* Can increase secretion of insulin, glucagon, growth hormones * Aids repair following injury and immune system stimulation. * Precursor of creatine, gamma amino butric acid (GABA, a neurotransmitter in the brain) * May increase sperm count and T-lymphocyte response

Aspartic Acid

* Aids conversion of carbohydrates into muscle energy * Builds immune system immunoglobulins and antibodies * Reduces catabolic ammonia levels after exercises

Cysteine

* Detoxifies harmful chemicals * Stimulates white blood cell activity

Glutamic Acid

* Precursor of glutamine, proline, ornothine, arginine, glutathione, and GABA * A potential source of energy for muscle tissue * Important in metabolism of other amino acids.

Glutamine

* The most abundant amino acid in the human body * Immune system builder * An important source of energy, especially for kidneys and intestines during caloric restrictions. * A brain fuel that is an aid to memory and promotes concentration

Glycine

* Aids in the manufacture of other amino acids * Has a calming effect * Assists in mobilization of glycogen * Can inhibit sugar cravings

Histidine

* Ultraviolet absorbing compounds in the skin * Important in the production of red and white blood cells * Used in the treatment of allergic diseases, rheumatoid arthritis and digestive ulcers.

Proline

* Component in the formation of connective tissue and heart muscle * Easily used for muscular energy

Serine

* Important in energy production in cells * Aids memory and nervous system function * Helps builds up immune system

Tyrosine

* Precursor of the neurotransmitters dopamine, norepinephrine and epinephrine, as well as thyroid and growth hormones * Elevates mood

Taurine

* Aids in the absorption and elimination of fats * May act as a neurotransmitter in some areas of the brain and retina

That leaves the essential amino acids that cannot be produced in the body which means they must be supplied by the diet. These are:

Isoleucine

* A branched chain amino acid easily taken up and used for energy by muscle tissue. * Used to prevent muscle wasting * Essential in the formation of haemoglobin

Leucine

* A branched chain amino acid used as a source of energy * Helps reduce muscle protein breakdown * Promotes healing of skin and broken bones.

Lysine

* Low levels can slow protein synthesis, affecting muscle and connective tissue * Inhibits viruses * Lysine and Vitamin C together form L-carnitine, a biochemical that enables muscle tissue to use oxygen more efficiently which can delay exercise induced fatigue

Methionine

* Precursor of cystine and creatine * May increase antioxidant levels (glutathione) and reduce blood cholesterol levels. * Helps remove toxic wastes from the liver and assists in the regeneration of liver and kidney tissue

Ornithine

* May help increase growth hormone secretion in high doses * Aids in immune and liver function

Phenylalanine

* The major precursor of tyrosine * Enhances learning, memory, mood and alertness * Suppresses appetite

Threonine

* One of the amino detoxifiers * Helps prevent fatty build up in the liver * Important component of collagen * Tends to be low in vegetarian diets

Tryptophan

* Precursor of key neurotransmitter serotonin * Stimulates the release of growth hormones * Free form of this amino acid is unavailable in the U.S. * It is only available in natural food sources and may be indirectly obtained by HTTP-5 supplementation

Valine

* A branched chain amino acid * Influences brain uptake of other neurotransmitter precursors (trptophan, phenylalanine and tryosine).

Well, you