Discover the Function, Sources and Benefits of the Health Supplement Ingredient L-Ornithine, or (S)-2,5-Diaminopentanoic Acid
Ornithine – also known as L-ornithine, (S)-2,5-diaminopentanoic acid or (S)-alpha,delta-diaminovaleric acid – is a crystalline amino acid. Different sources refer to it as 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, injury or stress. L-ornithine is found in some food sources as well as in health and bodybuilding supplements such as HGH 30,000 Nanograms pills and HGF MAX.
Functions of L-Ornithine
Together with arginine and citrulline, ornithine is one of three amino acids that play a key role in the urea cycle. The conversion of arginine into ornithine and ornithine into citrulline increases urea production while lowering ammonia concentrations in the blood. Citrulline subsequently binds with aspartate to form arginosuccinate, which breaks down into free arginine and fumarate; through this process, ornithine is metabolized back into arginine by the liver. Because L-ornithine helps accelerate the excretion of ammonia, it is believed to promote proper liver function, prevent fatigue and enhance performance during prolonged exercise. Evidence also suggests that L-ornithine may stimulate human growth hormone (HGH) production, thereby serving as a natural HGH releaser.
Sources of L-Ornithine
The human body manufactures ornithine from the amino acid arginine as part of the urea cycle. Dietary sources of L-ornithine include protein-rich foods such as beef, chicken, pork, fish, eggs, dairy products, peanuts and soybeans. L-ornithine may also be consumed in natural dietary supplements.
L-Ornithine Benefits and Uses
Among the benefits of ornithine is its ability to detoxify ammonia levels in the bloodstream; because of this function, it can be used to treat hepatic encephalopathy (a brain complication caused by liver disease). It also appears to help reduce fatigue and mitigate the effects of alcohol consumption, improving sleep quality and decreasing negative feelings the next morning. In addition, L-ornithine may promote wound healing, contribute to immune system function, support weight management, reduce stress and improve overall mood. Some evidence suggests L-ornithine acts as a natural HGH releaser, or HGH secretagogue. Because of its ability to boost HGH production and reduce fatigue, L-ornithine supplements are often taken to improve athletic performance, enhance muscle growth and increase endurance.
Side Effects of L-Ornithine and Potential Interactions
L-ornithine supplements are generally considered safe for adults; no serious side effects or drug interactions have been reported at doses of 2 to 6 grams per day. However, excessive doses (more than 10 grams per day) may potentially cause intestinal distress or diarrhea in some users.
More detailed safety information on L-ornithine dosing, side effects and interactions can be found on Examine.com. As with any medication or health supplement, it is best to consult your physician before taking dietary supplements containing L-ornithine.
L-Ornithine Research and Studies
Various research studies have shown that L-ornithine can be used therapeutically for certain medical conditions as well as to enhance overall health, well being and athletic performance. For example, a group of Polish researchers reported that L-ornithine-L-aspartate (LOLA) supplementation has the ability to lower blood ammonia concentration, eliminate symptoms of hepatic encephalopathy associated with liver cirrhosis and stimulate tissue regeneration, while a Japanese study determined that healthy office workers who consumed a combination of caffeine and ornithine had higher mood ratings, less fatigue and better concentration than those who consumed caffeine alone. Japanese researchers also tested the effects of L-ornithine on salivary cortisol, mood and feelings of fatigue the morning after alcohol consumption, and found that L-ornithine supplements lowered cortisol levels, increased sleep length and significantly decreased feelings of fatigue, anger/hostility and confusion.
Study findings published in the Nutrition Journal and Nutrition Research revealed that L-ornithine not only has the potential to relieve stress and improve sleep quality in fatigued office workers, but also to reduce physical fatigue during exercise. Researchers stated that the decrease in physical fatigue is due to L-ornithine’s ability to modulate lipid and amino acid metabolism, thereby increasing the efficiency of energy consumption. Furthermore, a recent animal study published in the Brain Research Bulletin found that L-ornithine reduced body weight, abdominal fat and food intake in rats.
Beyond the research indicating L-ornithine’s potential to reduce fatigue and overall body weight, several studies suggest that it can improve strength and HGH levels. A study published in the Journal of Sports Medicine and Physical Fitness revealed that arginine and ornithine supplementation paired with a high-intensity strength-training program increased total strength and lean body mass in a relatively short period of time. The article also reported that the arginine and ornithine supplements aided in recovery from chronic stress by quelling tissue breakdown, as evidenced by lower urinary hydroxyproline levels. Furthermore, a double-blind study published in the Journal of Strength and Conditioning Research found that ornithine and arginine supplementation increased human growth hormone (HGH) and insulin-like growth factor-1 (IGF-1) serum levels after heavy-resistance exercise in strength-trained athletes. While further research is needed, the preliminary findings on L-ornithine supplements show significant promise for improving athletic performance, building muscle and elevating HGH levels.
For additional L-ornithine research, refer to the PubMed site sponsored by the National Institutes of Health (NIH).
HGH.com Supplements With L-Ornithine
Athletes, bodybuilders and fitness enthusiasts seeking to leverage the benefits of L-ornithine can find this amino acid among the ingredients in natural health and bodybuilding supplements from HGH.com:
HGH Pills – Purity Select’s HGH 30,000 Nanograms pills are formulated to boost growth hormone production with a powerful combination of L-group amino acids, including L-ornithine. As one of HGH.com’s best-selling products, these capsules help promote muscle growth, increased energy, fat-burning and other health benefits.
HGF MAX – Scientifically designed to increase HGH production, these Purity Select capsules contain a proprietary blend of ingredients including L-ornithine and other key amino acids. Taking HGF MAX as a dietary supplement can help build muscle, enhance muscle tone, improve stamina and increase metabolism.
References (Function, Sources, Benefits/Uses and Side Effects/Interactions):
Busch, Sandi. “Benefits of L-Arginine and L-Ornithine”; published in the “Nutrition Facts” section on Livestrong.com; July 13, 2014. <http://www.livestrong.com/article/502331-the-benefits-of-l-arginine-ornithine>
Examine.com. “Ornithine”; published under “Supplements”; accessed April 13, 2015. <http://examine.com/supplements/Ornithine>
Marie, Joanne. “What Does the Amino Acid L-Ornithine Do?”; published in the “Alternative Remedies” section on Livestrong.com; May 14, 2014. <http://www.livestrong.com/article/22017-amino-acid-l-ornithine>
National Center for Biotechnology Information, U.S. National Library of Medicine. “L-ornithine”; Compound Summary for CID 6262 in PubChem Open Chemistry Database; accessed April 13, 2015. <http://pubchem.ncbi.nlm.nih.gov/compound/L-ornithine>
Somera, Anna Lisa. “Foods With Ornithine”; published in the “Vitamins and Supplements” section on Livestrong.com; August 16, 2013. <http://www.livestrong.com/article/165604-foods-with-ornithine>
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>
WebMD and Natural Medicines Comprehensive Database. “Ornithine”; published under “Vitamins & Supplements”; accessed April 13, 2015. <http://www.webmd.com/vitamins-supplements/ingredientmono-200-ornithine.aspx?activeingredientid=200&activeingredientname=ornithine>
Demura, Shinichi; Takayoshi Yamada; et al. “The Effect of L-Ornithine Hydrochloride Ingestion on Performance During Incremental Exhaustive Ergometer Bicycle Exercise and Ammonia Metabolism During and After Exercise”; European Journal of Clinical Nutrition; October 2010. <http://www.ncbi.nlm.nih.gov/pubmed/20717126>
Elam, R.P.; D.H. Hardin; et al. “Effects of Arginine and Ornithine on Strength, Lean Body Mass and Urinary Hydroxyproline in Adult Males”; Journal of Sports Medicine and Physical Fitness; March 1989. <http://www.ncbi.nlm.nih.gov/pubmed/2770269>
Kokubo, Takeshi; Emiko Ikeshima; et al. “A Randomized, Double-Masked, Placebo-Controlled Crossover Trial on the Effects of L-Ornithine on Salivary Cortisol and Feelings of Fatigue of Flushers the Morning After Alcohol Consumption”; Biopsychosocial Medicine; February 18, 2013. <http://www.ncbi.nlm.nih.gov/pubmed/23414576>
Konishia, Yuuki; Yasutaka Koosaka; et al. “L-Ornithine Intake Affects Sympathetic Nerve Outflows and Reduces Body Weight and Food Intake in Rats”; Brain Research Bulletin; February 2015. <http://www.ncbi.nlm.nih.gov/pubmed/25526897>
Misaizu, Akane; Takeshi Kokubo; et al. “The Combined Effect of Caffeine and Ornithine on the Mood of Healthy Office Workers”; Preventative Nutrition and Food Science; December 2014. <http://www.ncbi.nlm.nih.gov/pubmed/25580405>
Miyake, Mika; Takayoshi Kirisako; et al. “Randomised Controlled Trial of the Effects of L-Ornithine on Stress Markers and Sleep Quality in Healthy Workers”; Nutrition Journal; June 3, 2014. <http://www.ncbi.nlm.nih.gov/pubmed/24889392>
Sikorska, Hanna; Janusz Cianciara; and Alicja Wiercińska-Drapało. “Physiological Functions of L-Ornithine and L-Aspartate in the Body and the Efficacy of Administration of L-Ornithine-L-Aspartate in Conditions of Relative Deficiency” (article published in Polish); Polski Merkuriusz Lekarski; June 2010. <http://www.ncbi.nlm.nih.gov/pubmed/20642112>
Sugino, Tomohiro; Tomoko Shirai; et al. “L-Ornithine Supplementation Attenuates Physical Fatigue in Healthy Volunteers by Modulating Lipid and Amino Acid Metabolism”; Nutrition Research; November 2008. <http://www.ncbi.nlm.nih.gov/pubmed/19083482>
Zajac, Adam; Stanisław Poprzęcki; et al. “Arginine and Ornithine Supplementation Increases Growth Hormone and Insulin-Like Growth Factor-1 Serum Levels After Heavy-Resistance Exercise in Strength-Trained Athletes”; Journal of Strength and Conditioning Research; April 2010. <http://www.ncbi.nlm.nih.gov/pubmed/20300016>