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 an amino acid that performs several functions in the human body. L-Arginine not only helps in getting rid of the ammonia but also aids the formation of nitric oxide, a compound responsible for relaxation of blood vessels. This amino acid is also involved in the formation of protein in human body. Besides stimulating the release of prolactin and growth hormones, L-Arginine can help in the treatment of heart diseases as it increases blood flow and improves the function of the blood vessels. It is effective for treating erectile dysfunction and heals wounds effectively. L-Arginine is produced in the liver as well as the kidney. Food items which include this acid are animal proteins like meat, fish, poultry and plants. L-Arginine supplements become essential when the supply of arginine depletes because of infections and severe burns.

L-Aspartic Acid is a proteinogenic alpha amino acid, one of the twenty that are deemed the building blocks of proteins. L-Aspartic Acid is considered non-essential, because the human body can produce it from the organic compound oxaloacetate through a process called transamination. Despite L-Aspartic Acid being classified as non-essential, it is available through dietary sources such as luncheon meats, wild game meat, sausage meat, oat flakes, avocadoes, asparagus and various sprouting seeds. L-Aspartic Acid is also playing a role in the removal of ammonia, but also as a precursor and in the production and synthesis of various biochemical compounds such as arginine, isoleucine, threonine, asparagine, lysine and some nucleotides. In recent years studies have revealed that L-Aspartic Acid seems to raise the body’s resistance to fatigue, thereby boosting endurance.

L-Cysteine can be used to help with skin health. It also has been known to stop hair loss & aid normal hair growth. In some studies L-Cysteine has shown to Help the body's natural detoxification process and Enhance absorption of iron. L-Cysteine also Supports the production of red & white blood cells.

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 is an essential alpha-amino acid that is considered both, a ketogenic and a glucogenic amino acid. Since that L-Isoleucine is an essential amino acid, it cannot be synthesized by the body, therefore it needs to be ingested. The primary source of L-Isoleucine is as a component of proteins. It has become a prominent component of nutritional supplements, mostly with the body building and similar athletic communities, where it is believed that L-Isoleucine has the capability to increase endurance, but also to repair muscle tissue. It has been observed that L-Isoleucine ingestion allows power athletes to recover easier from very tough trainings and exhausting activities. This branched chain amino acid is one of the three main BCAA in the body, the other ones being valine and leucine.

L-Leucine is useful in conjunction with L-Valine and L-Isoleucine as an amino acid supplement. L-Leucine is an amino acid that a body cannot produce on its own. It is expected to be received externally from food sources such as brown rice and nuts or even through some of the dietary supplementation. L-Leucine is showing numerous advantages in the athletic qualities. Within six week of training with L-Leucine in association, a person is able to maximize the aerobic power. In the six weeks the strength and power in the upper body increases. However, research and studies is limited carried on the athletic performance. L-Leucine incorporated into the muscle protein in continuation with two weeks exercise regime will give adequate resistance and the muscle protein synthesis will certainly show an increase. L-Leucine is a preservative of the muscles, but is as well a supplement that enhances the capabilities of muscle building owing to the enhanced protein synthesis rate.

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 optimizes the utilization of animals that you consume in order to deposit protein to the muscles and aides in weight gain.

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, a non-essential amino acid that is used to build protein. It is a precursor dopamine, as well as a precursor to norepinephrine and epinephrine. The body makes L-Tyrosine from the amino acid phenylalanine. Since L-Tyrosine is a precursor of Dopamine, it may raise mental alertness, making it of great use in exercise programs.

L-Valine, an essential amino acid, promotes the smooth functioning of the body. It is derived from animal and vegetable proteins like seafood, poultry, meat, cottage cheese, sesame seeds, dry whole lentils and roasted peanuts. It regulates the immune system, assists protein synthesis and glucose metabolism. It also promotes growth of muscles and repair of tissues that get damaged due to stress, disease, surgery or injury. It maintains the body’s nitrogen level and energizes the muscles. L-Valine helps detoxify the body against ammonia and prevents muscle wasting in diabetics. It assists in correcting drug addiction related amino acid deficiencies, gallbladder and liver diseases and is linked with treating neurological conditions and brain damage due to alcohol intake. One should consult a physician before consuming the supplement.