Glycine is the simplest amino acid synthesized in the body. It is the only amino acid not optically active because it has no stereoisomers (compounds with the same molecular formula but a different structural formula). Glycine is essential for synthesizing nucleic acids, bile acids, proteins, peptides, purines, ATP, porphyrins, hemoglobin, glutathione, creatine, bile salts, glucose, glycogen, and other amino acids. The liver uses glycine to help detoxify compounds and synthesize bile acids. Glycine has a sweet taste and is used as a sweetener/taste enhancer. Glycine is an inhibitory neurotransmitter in the central nervous system (CNS), is a metal complexing agent, retards muscle degeneration, improves glycogen storage, and promotes healing.
The measurement of alanine, along with 23 other amino acids, is included in the Amino Acids in Plasma and the Amino Acids in Urine tests as well as in the Neurotransmitter Profile.
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Glycine (Gly/G) is one of the non-essential amino acids. It is used to build muscle tissue and convert glucose into energy. It is also essential to keep the central nervous system and gastrointestinal tract healthy, and it has recently been shown to protect antioxidant mechanisms against certain types of cancer.
Glycine helps prevent muscle breakdown by boosting the body's creatine levels, which helps build muscle mass. High glycine concentrations are found in muscle and skin, ligaments and tendons, and other connective tissues. Almost 1/3 of collagen, which keeps skin and connective tissue firm and flexible, comprises glycine. Without glycine, the body could not repair damaged tissues, the skin would become loose as it was damaged by UV rays, oxidation, and free radical damage, and injuries could never heal.
Glycine is a glucogenic amino acid that helps supply the body with glucose for energy production and regulates blood sugar levels. Therefore, glycine supplementation can be helpful in treating symptoms of low energy and fatigue, such as hypoglycemia, anemia, and chronic fatigue syndrome (CFS).
Glycine is essential for a healthy and functioning digestive system. It helps regulate the synthesis of bile acids used to digest fats.
Glycine is essential for the functioning of the central nervous system. Research has shown that this amino acid can help inhibit neurotransmitters that cause hyperactivity, such as seizure activity and manic (bipolar) disorder. Glycine can also be converted to another neurotransmitter, serine, when needed and may be beneficial in the management of schizophrenia. Studies have shown that glycine also helps improve memory in patients suffering from various medical conditions that affect sleep, such as schizophrenia, Parkinson's disease, Huntington's disease, jet lag, and fatigue.
Preliminary studies have shown that glycine may help prevent the development of cancerous tumors and melanoma. Glycine also appears to play a role in maintaining prostate health.
Glycine is the best dietary source from foods high in protein, such as fish, meat, beans, milk, and cheese. High amounts of glycine are also found in gelatin, a denatured collagen form. Glycine is also available in capsule and powder form and as part of many amino acid supplements. There are no toxic effects associated with glycine, although some report that taking this supplement causes stomach upset.
People with kidney or liver disease should not consume glycine without consulting their doctor. Taking any amino acid supplement can stop the citric acid cycle (Krebs cycle) and cause nitrogen or ammonia to build up in the body, which causes the liver and kidneys to work harder to remove waste. Anyone taking anti-seizure medications should consult their doctor before supplementing with glycine, as it may increase the effects of these medications.