Discover the Function, Sources and Benefits of the Health Supplement Ingredient L-Glycine, or Aminoacetic Acid
Glycine – also known as L-glycine, aminoacetic acid or aminoethanoic acid – is the smallest of the 20 amino acids in the human body. It is considered a nonessential or conditionally essential amino acid, which means that it is normally produced by the body in sufficient amounts; however, dietary supplementation may be beneficial in times of illness or stress, or for the treatment of certain diseases. L-glycine is found in some food sources as well as in health and bodybuilding supplements such as HGF-MAX, HGH 30,000 Nanograms pills and spray, and whey protein mixes.
Functions of L-Glycine
As an amino acid, glycine is involved in protein synthesis. It appears to work in concert with L-glutamine to improve brain function, and it is one of three amino acids – along with proline and hydroxyproline – that make up the triple-helical structure of collagen. Evidence also suggests that L-glycine may stimulate human growth hormone (HGH) production, acting as a natural HGH releaser.
Sources of L-Glycine
The body manufactures glycine using another amino acid called serine. Dietary sources of l-glycine include protein-rich foods such as meat, fish, dairy and legumes. L-glycine may also be consumed as an ingredient within natural dietary supplements.
L-Glycine Benefits and Uses
Therapeutic uses of L-glycine include the treatment of schizophrenia, stroke and leg ulcers. It also appears to enhance wound healing, and may help protect the liver and kidneys from the harmful effects of certain chemicals. Evidence suggests that L-glycine functions a natural HGH releaser, or HGH secretagogue; as a result, it may have a beneficial effect on athletic performance, such as helping to build muscle and increase endurance.
Side Effects of L-Glycine and Potential Interactions
L-glycine supplements are generally considered safe for adults; no serious side effects have been reported, even at doses as high as 60 grams per day. A small number of people have experienced stomach upset, nausea or vomiting, which ceased as soon as L-glycine supplementation was discontinued.
While L-glycine appears to enhance the beneficial effects of most drugs used to treat schizophrenia, it has been shown to decrease the effectiveness of one particular antipsychotic drug known as clozapine (Clozaril). Patients taking clozapine should avoid L-glycine supplementation.
More detailed safety information on L-glycine side effects and interactions can be found on the NYU Langone Medical Center website. As with any medication or health supplement, it is best to consult your physician before taking dietary supplements containing L-glycine.
L-Glycine Research and Studies
In addition to research on the use of glycine to treat medical conditions such as schizophrenia and strokes, a number of studies have explored the impact of L-glycine on HGH secretion. One such study published in Acta Endocrinologica found that intravenous glycine infusions produced a significant increase in serum HGH levels. Another study cited in Nutritional Neuroscience indicated that an oral supplement containing glycine, glutamine and niacin increased HGH secretion in healthy middle-aged and elderly subjects. In Nutrients as Ergogenic Aids for Sports and Exercise, the author conducted a research review and summarized his findings; he noted that a number of studies concur that glycine appears to stimulate HGH release and promote creatine synthesis, which can be beneficial for athletes undergoing progressive weight training.
Several other studies have examined the effects of L-glycine supplementation in relation to athletic performance and recovery. In Medicine & Science in Sports & Exercise, researchers found that an oral treatment of glycine and L-arginine salt of alpha-ketoisocaproic acid calcium (GAKIC) increased muscle torque and work sustained during intense acute anaerobic dynamic exercise, and enhanced overall muscle performance by delaying muscle fatigue during the early phases of anaerobic dynamic exercise. A recent animal study featured in Connective Tissue Research explored the effects of green tea and glycine on tendinitis, which commonly afflicts athletes, and determined that a green tea and glycine diet has beneficial effects that aid in the recovery process of the tendon after tendinitis.
For additional L-glycine research, refer to the PubMed site sponsored by the National Institutes of Health (NIH).
HGH.com Supplements With L-Glycine
Athletes, bodybuilders and fitness enthusiasts can experience the beneficial effects of L-glycine for themselves with natural HGH releasers and bodybuilding supplements from HGH.com:
HGH Pills and HGH Spray – Whether you prefer HGH pills or an oral spray, Purity Select’s 30,000 Nanogram products promote growth hormone production with a powerful combination of L-group amino acids, including L-glycine. They are designed to support muscle growth, fat-burning, increased energy and other health benefits.
HGF MAX – Scientifically formulated to naturally boost HGH production, these Purity Select capsules contain a proprietary blend of ingredients including L-glycine and other amino acids, which can help build muscle, improve muscle tone, increase stamina and boost metabolism.
Multi-Pro Chocolate Whey Protein – With over 450 milligrams of L-glycine and 24 grams of protein per serving, Multi-Pro is a complete protein supplement that is intended to help users build muscle, reduce body fat and support immune system health.
CytoSport Vanilla Whey Protein – A single serving of low-lactose, low-fat, CytoSport whey protein contains 2 grams of L-glycine and 18 grams of protein. This delicious drink mix is formulated to help athletes increase lean muscle mass and accelerate recovery from intense training.
References (Function, Sources, Benefits/Uses and Side Effects/Interactions):
NYU Langone Medical Center. “Glycine”; published under “Herbs & Supplements”; last reviewed September 2014. <http://www.med.nyu.edu/content?ChunkIID=21751>
University of Maryland Shore Regional Health. “Amino Acids”; published in the “Medical Reference Guide” section; last updated April 23, 2014. <http://umm.edu/system-hospital-sites/shore-health/health/medical/ency/articles/amino-acids>
Lodish, Harvey; Berk, Arnold; et al. “Collagen: The Fibrous Proteins of the Matrix”; Molecular Cell Biology, 4th Edition; New York: W.H. Freeman; 2000; section 22.3. <http://www.ncbi.nlm.nih.gov/books/NBK21582/>
WebMD and Natural Medicines Comprehensive Database. “Glycine”; published under “Vitamins & Supplements”; accessed November 21, 2014. <http://www.webmd.com/vitamins-supplements/ingredientmono-1072-glycine.aspx?activeingredientid=1072&activeingredientname=glycine>
Arwert, Lucia I.; Deijen, Jan Berend; and Drent, Madeleine L. “Effects of An Oral Mixture Containing Glycine, Glutamine and Niacin on Memory, GH and IGF-I Secretion in Middle-aged and Elderly Subjects”; Nutritional Neuroscience; October 1, 2003. <http://www.ncbi.nlm.nih.gov/pubmed/14609312>
Bucci, Luke R. “Micronutrient Supplementation and Ergogenesis — Amino Acids: Glycine”; Nutrients as Ergogenic Aids for Sports and Exercise; Boca Raton: CRC Press; 1993; chapter 6, section VI, pages 73-74. <http://www.crcpress.com/product/isbn/9780849342233>
Dannhardt, Gerd and Kohl, Beate K. “The Glycine Site on the NMDA Receptor: Structure-Activity Relationships and Possible Therapeutic Applications”; Current Medicinal Chemistry; August 1998. <http://www.ncbi.nlm.nih.gov/pubmed/9668194>
Kasai, K.; Suzuki, H.; et al. “Glycine Stimulated Growth Hormone Release in Man”; Acta Endocrinologica; March 1980. <http://www.ncbi.nlm.nih.gov/pubmed/7376793>
Stevens, Bruce R.; Godfrey, Michael D.; et al. “High-Intensity Dynamic Human Muscle Performance Enhanced by a Metabolic Intervention”; Medicine & Science in Sports & Exercise; December 2000. <>
Vieira, Cristiano P.; Da Ré Guerra, Flavia.; et al. “Green Tea and Glycine Aid in the Recovery of Tendinitis of the Achilles Tendon of Rats”; Connective Tissue Research; November 21, 2014. <http://www.ncbi.nlm.nih.gov/pubmed/25360832>