L-Alanine is considered as a supplementary amino acid. The presence of carbon atom in its composition leads to the formation of L alanine, which is organic in nature. The best sources of L-alanine would be fish, beef, pork and poultry. The various protein sources which are animal based would consist of a good amount of l-alanine. The alanine levels increases with the contraction of muscles in the body. L- alanine is used by the body to build proteins. It also helps in the transfer of nitrogen from the tissues in our body. It helps to draw blood sugar and hence acts as a good energy resource producer. This would be best suited for those who want a reduction in extra body fat.

L-Arginine is a very important amino acid that is required by the body for a number of functions. One of the main functions of L-Arginine is its ability to rid the body of ammonia, which is a waste product. It is also used in the manufacture of nitric oxide, which helps to relax the blood vessels, thereby increasing the flow of blood and reducing the chances of a heart attack. It is advised that supplements of L-Arginine should not be administered following a heart attack for fear that it could possibly aggravate cardiac shock. L-Arginine is being used in treating people with erectile dysfunction, as it relaxes the blood vessels surrounding the penis. It is also used in treating migraine and blood pressure.

L-Aspartic Acid is deemed non essential in humans, since that it can be transaminated from oxaloacetate. Natural sources of L-Aspartic Acid are sugar cane and sugar beets, among others, like beef, poultry, eggs, potatoes, dairy, etc. Asparagine, which is deemed a synonym for L-Aspartic Acid, is required by the nervous system, but it also plays a vital part in the synthesis of ammonia. As an important participant in the citric acid circle in human metabolism, L-Aspartic Acid is vital for the proper function of many other amino acids and biochemical components, such as lysine, methionine, asparagine, arginine and isoleucine. L-Aspartic Acid seems to be able to increase stamina, thereby increasing the endurance in athletic competitions and workout regimes; furthermore it seems to increase the body’s resistance to fatigue.

L-Cysteine- If two cysteine molecules are bound together by a disulfide structural unit, the amino acid dimer L-Cystine is formed. It is deemed a vital component of proteins, where formations of the disulfide bonds are made between and within protein molecules. It seems that thereby L-Cystine is determining to a significant amount the three dimensional structure of a prominent number of proteins. For instance, it has been determined that human hair contains about five percent of cystine. In case that the non-essential alpha amino acid cysteine is required by the body, the disulfide link is apparently readily reduced. While cysteine can be derived from protein rich sources such as meat, poultry and dairy products, L-Cystine, although present in these, is most abundantly found in undenatured whey proteins.

L-Glutamic Acid- In the proteinogenic group of twenty amino acids, the group that is deemed the building blocks of proteins, L-Glutamic Acid is one of the more commonly known ones. The reason for this fame are the carboxylate anions and salts of the glutamic acid, the glutamates. Glutamic acid is present in many fermented or aged food sources, such as cheese and soy sauce, but also in yeast extracts. The sodium salt of glutamic acid, monosodium glutamate, is a very popular and widely used food additive. Glutamate is an extremely important molecule in cellular metabolism. Glutamate is also one of the most commonly occurring excitatory neurotransmitters. Glutamate has been also identified as a precursor to GABA inhibitor. Glutamic acid is deemed responsible for one of the five basic tastes, the human taste sense commonly called umami.

L-Glycine- Glycine is an organic compound and one of the 20 amino acids deemed as building blocks for proteins. This proteinogenic amino acid is not only the smallest but also the only amino acid of the group that is not chiral, which means there is no enantiomer of glycine. With the prominent exception of collagen, which thirty five percent are glycine, most proteins contain only small amounts of it. As a solid, glycine is sweet tasting, crystalline and has no color. Despite being non-essential, because it can be biosynthesized from the amino acid serine, glycine has several important physiological functions, besides being a precursor to proteins. It is a biosynthetic intermediate of purines and the D-Aminolevulinic acid and it is an inhibitory neurotransmitter found in the central nervous system.

L-Histidine is one of the amino acids present in proteins. In infants histidine is an essential amino acid and as the age advances it becomes a non-essential amino acid which can be synthesized by the body. L-Histidine is most commonly known as being a precursor to the allergy symptom producing hormone histamine. However histadine does have other roles to play in the body beyond causing allergies. L-Histadine is required by the body to regulate and utilise essential minerals like copper, zinc, iron, manganes etc. L-Histidine is also important in forming metal bearing enzymes like the antioxidant super oxide dismutase, iron storage proein ferritin, red blood cell haemoglobin etc. Depletion of L-Histidine can be recognised by low plasma concentrations of the amino acid, high blood serum levels.

L-Isoleucine is one of the amino acids besides the other two, L-Valine and L-Leucine. These are found in all the forms of life as proteins. They are as well obtainable in the diet through vegetable and animal sources. L-Isoleucine is good to regulated blood sugar as well the energy levels. It is also important in the synthesis of hemoglobulin and thereby increases endurance. L-Isolecuine gets metabolized in the tissues of the muscles and the opulent L-Isolecuine sources are almonds, cashews and soy protein. Hence, this is prominent among athletes and is taken in combination with the other two amino acids, L-Leucine and L-Valine. L-Isoleucine is required for the formation of hemoglobin and also regulates as well as stabilizes the energy levels. The other food sources of L-Isoleucine are eggs, meat, fish, rye, chickpeas, chicken, liver and lentils. People suffering from physical and mental disorders are usually deficient in L-Isoleucine. These amino acids are required for the synthesis of enzymes, structural protein and for hormones.

L-Leucine with the food additive E number code E641 is classified as a flavor enhancer. Leucine is actually an essential alpha-amino acid and a vital part of so called “buffer” proteins, such as ferritin and astacin. You can find leucine in foods such as whole wheat bread products, nuts and brown rice. As a supplement, researchers have found that leucine slows the degradation of muscles and muscle tissues through an inflated synthesis of muscle proteins. In the human body, leucine can be found in the liver, but most prominently in the muscle and adipose tissues, where it is utilized in production of sterols. In body building circles L-Leucine as a dietary supplement is very popular for all these properties, but also for the preservation of muscle glycogen, nitrogen balance maintenance and more.

L-Methionine- One of the most significant amino acids there is for the breaking down of fats. It is water-soluble and is known for deactivating free radicals. Recognized as being a leading antioxidant.

L-Phenylalanine gained notoriety with the aspartame controversy where extensive internet bombardment against the artificial sweetener prompted a thorough cleaning by The Coca Cola Company and other interest groups. Now it seems that aspartame has more benefits to health than aspirin. L-Phenylalanine is an essential alpha amino acid that is deemed analgesic and antidepressant. It is hydrophobic and nonpolar, one of only twenty common amino acids that are used to produce protein as coded by the DNA. L-Phenylalanine can also convert into L-Tyrosine, which can then become L-DOPA, going forth to become norepinephrine, dopamine or epinephrine. Phenylalanine is very often found in foods, protein rich foods like meat, milk and milk products, poultry and fish, but also as already mentioned in the artificial sweetener aspartame.

L-Proline is a proteinogenic alpha amino acid, one of only twenty amino acids that are DNA encoded for the forming of protein. It is not deemed essential because humans are able to synthesize it from the amino acid L-Glutamate. This unique member of the twenty protein building block amino acids is the only one of the group that is distinct as belonging to the secondary alpha amino group. L-Proline plays a role in the synthesis of collagen. Collagen is undeniably the most common protein in mammals, being found in skin, tendons, joints, ligaments, vasculature and bones. It is deemed good for the health of joints, when taken as a supplement. Low protein diets, vegetarian and vegan diets as well as malnutrition lead to diminished L-Proline levels.

L-Serine- Serine is an organic compound and a proteinogenic amino acid that is considered a building block for the creation of proteins. This member of the hydroxyl group and a polar amino acid is not essential and therefore it is not necessary to ingest it by means of diet. L-Serine can be synthesized from metabolites such as glycine. L-Serine plays a role in the biosynthesis of pyrimidines and purines, furthermore it is a precursor to many metabolites like sphingolipids and to amino acids like cysteine and glycine. It is also involved in catalytic functions of several enzymes. L-Serine can be transformed into D-Serine by the serine racemase, which functions as a neuronal signal and NMDA receptor activator in the brain, a vital glutamate receptor responsible for memory functions and synaptic plasticity.

L-Threonine is an essential alpha amino acid, classified as polar. There are three proteinogenic amino acids that have an alcohol group, besides threonine there are tyrosine and serine. Like many other amino acids that are not synthesized in humans, threonine needs to be ingested through protein food sources that contain it, namely meat, poultry, cottage cheese, fish, sesame seeds and others. When ingested, threonine goes either through the threonine dehydrogenase and becomes pyruvate or, as in humans, it can be converted by the enzyme serine dehydratase to alpha ketobutyrate and continue towards succinyl-CoA. Threonine is also supposed to assist the protein balance by maintaining normal growth, but in addition to that, it seems to support the immune system, the central nervous system, the liver and the cardiovascular system.

L-Tryptophan- Tryptophan is an essential amino acid as well as within the group of only twenty standard amino acids that are required by the human diet. It is one of the building blocks required for protein biosynthesis. It is also viewed as a precursor to serotonin and thereby also melatonin, niacin and also auxin. Interestingly enough, lactose intolerance and fructose malabsorption have the side effect that tryptophan is only improperly absorbed in the intestines which leads to diminished levels of it in the system. Dietary sources of tryptophan are plentiful, it can be found in red meat, poultry, fish, milk, milk products, peanuts, mangoes, dates, chocolate and oats, among others. As a dietary supplement tryptophan has found applications as a safe sleeping aid and also as a calming agent.

L-Tyrosine is a protein non-essential building block Although non-essential it is important for the structure of body proteins. It has a direct effect on neurotransmitters.

L-Valine is an amino acid in combination with L-Leucine and L-Isoleucine. These amino acids maintain everyday life and offer maximum support. L-Valine is acquired from vegetable and animal protein. L-Valine regulates the immune system and is involved in the protein synthesis and glucose metabolism. L-Valine is effective in muscle growth as well as tissue repair. L-Valine is a part of the muscle metabolism and is also effective in the nitrogen balance in the body. L-Valine is found in the muscles in high concentration, but this cannot be done on its own in the body and has to be acquired through dietary or food supplements. L-Valine has stimulating effect and maintains the nitrogen in the body. It is effective for repair as well as growth of tissues and for muscle metabolism. Adhering to the label directions is highly recommended. This is normally safe and has no side effect until now. However, for the dietary supplement consulting the physician before use is the best.