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 very significant in producing energy. Helps to move NADH to the proper energy producing section of the body. This allows the NADH to make ATP the fuel power for cells.

L-Cysteine is one of the many naturally occurring amino acids. It is further termed as a protein amino acid. Promoting the stomach lining health is one of the main functions of l-cysteine. It also helps in correction of situations where the essential nutrients from food sources are not being absorbed properly. Generally, most people do not need supplements for obtaining l-cysteine amino acid. It is can easily be found in vegetable, meats and dairy products. Although, l-cysteine is also available in the form of cysteine, which is found in plenty of protein enriched foods. Cysteine is one of those amino acids which are not destroyed by cooking. On the contrary, research shows that cooking of food rich in cysteine may help you absorb them better.

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 an amino acid that is essential to the body, but is not produced by the body. It is made available through various food sources. Histidine helps in the manufacture and repair of tissues in the body, and in the formation of red and white blood cells which help in the treatment of anemia. It is also used for the production of gastric juices by the stomach. A deficiency in Histidine can lead to cataract and rheumatoid arthritis. Besides this, it is also a well known component of the skin that protects it by absorbing the ultra violet rays of the sun. A variety of foods such as meat, legumes, seafood, nuts, poultry and dairy products are providers of the required amounts of L-Histidine.

L-Isoleucine- The second of three branched chain amino acids it is important in blood sugar regulation and producing hemoglobin. After exercise, it is responsible for muscle recovery and important in the metabolism to produce energy.

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-Lysine is an essential amino acid obtainable from daily food sources we consume. It has many medicinal properties which benefit us in our daily lives. While it is mainly used in the treatment of herpes, it also helps us become stronger by building our muscle tissues. It helps us to recover form injuries and surgeries besides absorbing calcium for building healthy bones. It also regulates the production of antibodies, enzymes and hormones which are required for healthy immunity level. L-lysine when consumed in high doses can lead to serious conditions. Although L-lysine is important for good health, we never really realize we are consuming it. Deficiency of L-lysine causes lethargy, amnesia, enzyme disorders, reproductive problems and hair loss. Generally, L-lysine is present in all vegetarian and non-vegetarian foods. Fish and cereals have higher amount of L-lysine in them.

L-Methionine is an essential amino acid, actually an alpha amino acid, furthermore classified as nonpolar. This proteinogenic amino acid is the only one, besides cysteine, which contains sulfur. Methionine serves as an intermediate of phospholipids, such as phosphatidylcholine, but also lecithin, taurine, carnitine and cysteine. If methionine cannot be properly synthesized, the condition can lead to atherosclerosis. While it must be supplied with diet, this amino acid is deemed a powerful antioxidant, believed to be a scavenger of free radicals, and may assist with the breakdown of fats. Sources of L-Methionine include poultry and related products, including eggs, but also other meats, such as beef, cheese and fish. Methionine adenosyltransferase is converting methionine to S-adenosylmethionine, SAM, which in turn is involved in the creation of creatine, epinephrine, melatonin and further substances.

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 is the L-stereoisomer of the essential amino acid tryptophan. All amino acids consist of a basic structure which is different only in their special groups called functional groups. The amino acid tryptophan has an indole functional group. Tryptophan is an essential amino acid. This means that it must be ingested from an outside source. An example of a food item rich in this amino acid is banana. Basically, all amino acids are important for the body because they are the building blocks of proteins. Amino acids also possess some special features which vary according to the type of amino acid. Tryptophan also serves as a biochemical precursor of various substances in various reactions. It is a precursor of the neurotransmitter serotonin which is involved in regulating mood and gut movements. It can also act as a precursor of niacin.

L-Valine is the third branched chain amino acid and is required for muscle metabolism, repairs and regenerates tissue, and maintains the body's nitrogen level. It also is used as a muscle energy source and preserves the use of glucose.