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Amino acids are the basic building blocks of proteins in the body. There are nine essential amino acids and 11 non-essential amino acids1. Glycine is one such amino acid that is classified as non-essential. It was first discovered in the 1820s and researched heavily in the 1960s. In 1970, Hopkin & Neal2 were the first to show that applying stimulation releases glycine.

Since it was first discovered, scientists and researchers have learned much more about this important amino acid including how it functions in the body and the benefits it offers to not only healthy individuals but to those who suffer from a variety of medical conditions. Let's take a closer look at how glycine benefits the human body.

What Is Glycine?

Of all the amino acids used in protein synthesis, glycine is the smallest. It is comprised of a single carbon molecule that is attached to both an amino and carboxyl group3. Do not let its size fool you, it is of great importance. Glycine is a crucial component of numerous metabolic pathways in the human body. Glycine is derived from glyoxylate, glucose, betaine, threonine and L-carnitine4. Glycine is also a precursor for the synthesis of both RNA and DNA5.

Research shows that glycine degradation happens through three different pathways. The first is the glycine cleavage system. It serves as the major pathway for glycine degradation7. The second is serine hydroxymethyltransferase, which is involved in protein coding8 , and the third is conversion to glyoxylate by peroxisomal D-amino acid oxidase6.

Benefits of Glycine

Those with diabetes or typically have low plasma glycine levels typically benefit from glycine. Supplementation of glycine has been shown to improve glycine levels of individuals with diabetes as well as those who suffer from obesity4.

The most abundant protein in your body is surprisingly enough collagen. Glycine is the main component of collagen. Therefore, glycine is important in maintaining the structure of collagen in the human body9.

Tendinopathy of the Achilles Tendon is a painful medical condition thought to be the result of overuse of or repeated injuries of the Achilles Tendon10. In addition to pain, other symptoms include swelling and stiffness in the tendon. Research11 shows that because glycine has anti-inflammatory effects it may be beneficial in helping those who suffer from Achilles Tendinopathy heal faster.

The proper amount of quality sleep is important to rest and recharge the body. Glycine has been shown12 to improve the quality of sleep because it increases the blood flow to the bodies arms, legs, feet and hands as well as reduces your core body temperature.

Glycine supplementation is also effective in the treatment and prevention of disorders such as cancer, diabetes, obesity, inflammatory diseases and cardiovascular disease13.

Studies14 show that glycine enhances neurological functions. In particular, the consumption of glycine is suggested to be beneficial to individuals who suffer from psychotic and schizophrenic symptoms15.

How to Use Glycine

The body does synthesize glycine in the liver, but it is also found in certain food sources. Certain vegetables, fruits and high-protein foods are rich in glycine. Glycine is also popular as a dietary supplement in the form of capsules and powders that are taken orally in order to reap the health benefits.

Glycine Recommended Daily Allowance

Glycine supplementation is not regulated by the FDA and for this reason, there are no established recommended daily allowances. Research16 has suggested that high doses can cause toxic effects, but further studies are needed in order to establish a recommended dose range. When taking any dietary supplement, always follow the manufacturer's recommended dosing on the package.

When adding any new supplement to your diet, it is important to consult with your healthcare provider. Your medical doctor can take into account your current health condition, age and any current medications you may be on when recommending a proper dosage for your specific health concerns.

Foods That Contain Glycine

For individuals who want to consume additional glycine from the foods in their diet, there are a variety of options for those who are carnivorous as well as those who adhere to a vegan or vegetarian diet. Foods17 that are good dietary sources of glycine include:

  • Fish
  • Meat
  • Dairy
  • Pumpkin
  • Banana
  • Kiwi
  • Cucumber

Supplements are an option for those who either aren't able to consume enough glycine through their diet or prefer dietary supplements to ensure adequate consumption.

Glycine is already naturally produced by the body and participates in a variety of pathways. Consumption either through diet or supplements offers health benefits to those who suffer from insomnia, diabetes, obesity, cancer, cardiovascular disease and more! The smallest molecules can make the biggest difference in how we feel!

Glycine Supplementation With Total Sleep and Testro-X

There are always certain instances where diet is not going to give you everything you need. There's no need to worry if your diet does not provide the necessary amount of glycine. Oral supplements are available for those who want to make sure they are consuming enough in their daily diet.

Total Sleep and Testro-X are powerful, all-natural supplements that contains clinically-proven dosages of glycine and other herbs and nutrients. Total Sleep is specially designed to help you sleep naturally. Testro-X is engineered to restore balance to your hormonal ecosystem and optimize the endocrine system for testosterone production. Learn more about Total Sleep, Testro-X and UMZU's line of natural supplements by visiting our online showroom.

With crazy, busy schedules it is easy to be tempted by fast food, processed food, and an abundance of poor eating choices. With obesity and bad eating habits on the rise, it's more important now than ever to pay attention to what you put in your body. Your health is one of the most important investments you can make. After all, you will need it for years to come! Take care to make sure you are receiving adequate amounts of both macronutrients and micronutrients, as well as engaging in healthy exercise. Begin your journey to a healthier you today!

Citations and Sources

Medline Plus. Amino Acids. Accessed May 6, 2019.
Bowery N, Smart T. GABA and glycine as neurotransmitters: a brief history. Br J Pharmacol. 2006;147 Suppl 1:S109-19.
Hall J. Glycine. JPEN J Parenter Enteral Nutr. 1998;22(6):393-398.
Adeva-Andany M, Souto-Adeva G, Ameneiros-Rodríguez E, Fernández-Fernández C, Donapetry-García C, Domínguez-Montero A. Insulin resistance and glycine metabolism in humans. Amino Acids. 2018;50(1):11-27.
Liu L, Fu T, Xu X, et al. Tracing the nitrogen metabolites of glycine using (15)N-glycine and mass spectrometry. Rapid Commun Mass Spectrom. 2015;29(7):645-653.
Wang W, Wu Z, Dai Z, Yang Y, Wang J, Wu G. Glycine metabolism in animals and humans: implications for nutrition and health. Amino Acids. 2013;45(3):463-477.
Kikuchi G, Motokawa Y, Yoshida T, Hiraga K. Glycine cleavage system: reaction mechanism, physiological significance, and hyperglycinemia. Proc Jpn Acad Ser B Phys Biol Sci. 2008;84(7):246-263.
Appaji R, Ambili M, Jala V, Subramanya H, Savithri H. Structure-function relationship in serine hydroxymethyltransferase. Biochim Biophys Acta. 2003;1647(12):24-29.
de P-L, Lupiáñez J, Meléndez-Hevia E. High glycine concentration increases collagen synthesis by articular chondrocytes in vitro: acute glycine deficiency could be an important cause of osteoarthritis. Amino Acids. 2018;50(10):1357-1365.
Vieira C, De O, Da R, Dos S, Marcondes M, Pimentel E. Glycine improves biochemical and biomechanical properties following inflammation of the achilles tendon. Anat Rec (Hoboken). 2015;298(3):538-545.
Glycine. Accessed May 6, 2019.
Multifarious Beneficial Effect of Nonessential Amino Acid, Glycine: A Review. Oxidative Medicine and Cellular Longevity. Published March 1, 2017. Accessed May 6, 2019.
Razak M, Begum P, Viswanath B, Rajagopal S. Multifarious Beneficial Effect of Nonessential Amino Acid, Glycine: A Review. Oxid Med Cell Longev. 2017;2017:1716701.
Woods S, Walsh B, Hawkins K, et al. Glycine treatment of the risk syndrome for psychosis: report of two pilot studies. Eur Neuropsychopharmacol. 2013;23(8):931-940.
Pérez-Torres I, Zuniga-Munoz A, Guarner-Lans V. Beneficial Effects of the Amino Acid Glycine. Mini Rev Med Chem. 2017;17(1):15-32.
Glycine. Accessed May 6, 2019.
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