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 is an essential amino acid that works together with isoleucine and valine, forming the three branched chain amino acids (BCAA). Leucine is easily converted by to body to glucose, helping to regulate and maintain the blood sugar level. Leucine promotes muscle recovery, muscle repair and provides the body with energy. It also helps in burning fat that are least responsive to exercise and dieting. Leucine helps in toning the body and the muscles. Leucine prevents muscle loss by breaking down and converting to glucose, this prevents the body from breaking down muscle tissues to create energy, particularly during intense workouts and heavy weight lifting.

L-Lysine- Lysine is an essential alpha amino acid that needs to be ingested and cannot be synthesized by the human body. Sources of L-Lysine include meat, particularly red meat, lamb, poultry and pork, but also cheeses, like parmesan, some fish like cod and sardines and eggs. Several plants are rich in L-Lysine, soybean, lentil, spinach and buckwheat, but also buffalo gourd, watercress, locust bean and many other bean variants, including the common bean. L-Lysine is deemed vital for the overall production of protein, as a structural building block. It seems that L-Lysine also plays a prominent part in the absorption of calcium. Further properties include playing a role in the production of enzymes, hormones and antibodies, but also in the recovery from sports injuries and surgeries.

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 is a vital amino acid. It acts as a building block for various proteins produced in the body. It is found in most foods that contain protein, like poultry, beef, pork, milk, fish, yogurt, cheese, eggs, soy products, and certain nuts and seeds. It can assist in decreasing chronic pain linked with different health conditions by inducing nerve pathways in the brain which control pain. It can also help improve rigidity and is beneficial in conditions like walking disabilities, depression associated with Parkinson’s disease, and speech difficulties. Combination of L-Phenylalanine with ultraviolet radiation for people having vitiligo, a condition that is characterized by irregular depigmentation or white patches of skin, can lead to some darkening or repigmentation of whitened areas, especially on the face.

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-Valine is an essential alpha amino acid and one of the three essential branched chain amino acids found in the human body. The other two essential BCAAs are leucine and isoleucine. The name is derived from the plant valerian. Valine is also classified as nonpolar and is known by sickle cell disease sufferers as the substitute amino acid for the glutamic acid, whereby the hydrophobic qualities of valine cause the hemoglobin to not fold correctly. Just like the other three BCAAs, the primary source of valine is through ingestion of proteins, where valine is a component; some such sources would be fish, peanuts, poultry, cottage cheese, lentils and sesame seeds. L-Valine is found in large quantities in muscles, whereby in the muscle metabolism it is essential for the restoration and tissue growth.