Non-Essential Amino Acids: Biology’s Lego Bricks
Proteins are important for a healthy and balanced diet. Proteins are also important for almost all biological processes of our body and it comprises amino acids. Amino acids are an important pillar of metabolic processes occurring in our body. There are 21 amino acids that make up all the proteins in our body. These amino acids can be classified into two groups, namely “essential amino acids” and “non-essential amino acids”. But why do you need amino acids? Here we tell you all about non-essential amino acids benefits. Read on!
The main difference between essential and non-essential amino acids is that the former is not synthesized by our body and hence is an “essential” part of our diet. Eleven key amino acids(out of 21) are known as non-essential amino acids as they can be synthesized by the body. These are alanine, arginine, aspartic acid, cysteine, glutamic acid, glutamine, glycine, proline, serine, tyrosine, and asparagine.
Even though our body can produce non-essential amino acids, supplementing it in our diets rarely causes any harm. As a matter of fact, it might even be necessary in certain cases.
Let’s read on to find out more about how the non-essential amino acids benefits our health and why are they so important.
Alanine is produced in the body in the glycolytic pathway. The glycolytic pathway is the first biochemical step of converting glucose into energy. Alanine acts as an energy source for the brain and muscles. Moreover, it has a known role in immunity and even in the metabolism of sugars and amino acids.
Arginine is produced in the body from other amino acids. Its supplementation might be necessary in case of certain illnesses. It detoxifies nitrogenous wastes and also stimulates growth hormone release.
Aspartic acid is supplemented in the diet in the form of aspartate (salts of aspartic acid). A methyl ester of aspartic acid called Aspartame which is a zero-sugar artificial sweetener. It helps in the synthesis of many amino acids and also acts as a neurotransmitter (chemical messengers of the brain).
Cysteine is synthesized in the body from another amino acid called Methionine. Its supplementation may be required for infants to provide a healthy diet. It acts as a building block for collagen in the skin and beta-keratin in hair and nails. It is a food additive.
Glutamic acid, also known as Glutamate, works as a neurotransmitter. It works as a precursor for the synthesis of the inhibitory neurotransmitter GABA (Gamma-aminobutyric acid) and other amino acids such as glutamine and proline. GABA helps the neurons recover after sending a signal and prevents the nervous system to overwork itself to a point of burning out. Chemical industries synthesize MSG (monosodium glutamate) from Glutamic acid.
The body might require Glutamine supplementation during increased body demands such as heavy exercise or chronic illness. The muscles mainly produce Glutamine whereas the gastrointestinal and kidney cells mainly consume it. Glutamine acts as an energy source (for kidney, intestinal and nerve cells) and a buffer (maintains the acid-base balance in the blood). It also functions as a precursor for the neurotransmitters Glutamate and GABA.
Glycine acts as an inhibitory neurotransmitter and a precursor for haemoglobin synthesis. It can treat diabetic leg ulcers as well as ischemic stroke.
Proline acts as a building block of collagen. It is present in tendons, bones, cartilage and skin as well as in most of the biologically critical proteins in our cells. Proline supplements (L-proline) can improve symptoms of the inherited metabolic disorder ornithine aminotransferase deficiency.
Serine acts as a precursor for the synthesis of the amino acid tryptophan and also as a neurotransmitter in the brain. It also helps in fat metabolism and synthesis of purines, pyrimidines (building blocks of DNA) and creatine. Some serine supplements available in the market are L-serine, D-serine, LD-serine, and phosphatidylserine.
Tyrosine acts as a precursor of thyroid hormone, dopamine, norepinephrine (neurotransmitter), epinephrine (hormone) and melanin (a pigment found in skin, hair, and the iris). Consuming Tyrosine supplements can help improve alertness, memory and overall mental performance.
Asparagine is a precursor of aspartate. It is a mild diuretic (causing increased urination). Consequently, it also helps in the removal of nitrogenous wastes.
Although our body can produce all these amino acids, they are also present in our foods. Some sources of non-essential amino acids foods are meat, cheese, fish, legumes, nuts, and seeds. Thus, a healthy protein diet contains a proper combination of all these amino acids. Amino acids benefits our health and supplementation is not always necessary and may even have adverse effects in some cases.
- Lehninger Principles of Biochemistry Sixth Edition, David L. Nelson and Michael M. Cox
- Biochemistry, Donald Voet and Judith G. Voet
- Harper’s Illustrated Biochemistry, Robert K. Murray and Victor W. Rodwell