Glutamine - or L Glutamine - is traditionally considered a nonessential amino acid but may be conditionally essential in patients with catabolic (loss of muscle tissue due to disease) conditions. Glutamine -supplemented foods in these patients have been shown to prevent deterioration of gut permeability, protect against the development of intestinal mucosal atrophy, and improve nitrogen balance.
   Glutamine levels in plasma and skeletal muscle are decreased in those with cancer. Glutamine supplementation can attenuate loss of protein in the muscle and protect immune and gut-barrier function during radiochemotherapy in patients with advanced cancer.
     L-glutamine is the most prevalent amino acid in the blood. Human cells readily manufacture L-glutamine and under normal circumstances, dietary intake and production of L-glutamine is sufficient. However, in times of stress or increased energy output, the body's tissues need more L-glutamine than usual.

L Glutamine 1,000 mg, 90 Capsules - Club Natural

L-Glutamine has recently been the focus of much scientific interest. A growing body of evidence suggests that during certain stressful times, the body may require more glutamine than it can produce. Under these circumstances Glutamine may be considered a "conditionally essential" amino acid.  Glutamine is involved in maintaining a positive nitrogen balance (an anabolic state) and also aids rapidly growing cells (immune system lymphocytes and intestinal cell enterocytes).  In addition, Glutamine is a regulator of acid-base balance and a nitrogen transporter.

Glutamine Serving Size: 1 capsule

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Suggested Use: As a dietary supplement, take 1 glutamine capsule 1-3 times daily, preferably with meals, or as directed by your health care provider.

 

Benefit of Glutamine - Glutamine in Sports - Glutamine Research summary
Short-term ingestion of glutamine does not enhance weightlifting performance in resistance-trained men.
   Heavy exercise induces impairment of lymphocyte function. Ten male athletes participated in a randomized, placebo-controlled, double-blind crossover study. Each athlete performed bicycle exercise for 2 h at 75% of maximum O(2) consumption on 2 separate days. Glutamine or placebo supplements were given orally during and up to 2 hours post-exercise. Most lymphocyte subpopulations decreased 2 h after exercise. Glutamine supplementation abolished the post-exercise decline in plasma glutamine concentration but had no effect on lymphocyte trafficking, Natural killer cell activities, T cell proliferation, catecholamines, human growth hormone, insulin, or glucose. This study does not support the idea that glutamine plays a mechanistic role in exercise-induced immune changes.
   The combination of glutamine and creatine increases muscle mass and power.

Glutamine and HIV
Glutamine - antioxidant nutrient supplementation can increase body weight, body cell mass, and intracellular water when compared with placebo in HIV patients.
   Glutamine is helpful in those with HIV who are receiving certain types of anti-viral medicines.

L Glutamine side effects
Glutamine has few side effects except in massive doses. We are not aware of any glutamine side effects when used in low dosages. As to long term daily use of glutamine in high doses, we really don't know what potential danger, if any, it would have in the long run.

Glutamine Summary
Glutamine appears be helpful in those with cancer, HIV, or other medical conditions that lead to a catabolic state, but does not seem to play a significant role (by itself) in those who are healthy or provide any significant enhancement in athletic performance.

Glutamine Biochemistry
Glutamine and glutamate with proline, histidine, arginine and ornithine, make up 25% of the dietary amino acid intake and form the "glutamate family" of amino acids, which are disposed of through conversion to glutamate. Although glutamine has been classified as a nonessential amino acid, in major trauma, major surgery, sepsis, bone marrow transplantation, intense chemotherapy and radiotherapy, when its consumption exceeds its synthesis, it becomes a conditionally essential amino acid. In mammals glutamine is one of the most important substrate for ammoniagenesis in the gut and in the kidney due to its important role in the regulation of acid-base homeostasis. In cells, glutamine is a key link between carbon metabolism of carbohydrates and proteins and plays an important role in the growth of fibroblasts, lymphocytes and enterocytes. Deamidation of glutamine via glutaminase produces glutamate a precursor of gamma-amino butyric acid, a neurotransmission inhibitor. L-Glutamic acid is a ubiquitous amino acid present in many foods either in free form or in peptides and proteins. Animal protein may contain from 11 to 22% and plants protein as much as 40% glutamate by weight. The sodium salt of glutamic acid is added to several foods to enhance flavor. L-Glutamate is the most abundant free amino acid in brain and it is the major excitatory neurotransmitter of the vertebrate central nervous system. Most free L-glutamic acid in brain is derived from local synthesis from L-glutamine and Kreb's cycle intermediates. It clearly plays an important role in neuronal differentiation, migration and survival in the developing brain via facilitated calcium transport. Glutamate also plays a critical role in synaptic maintenance and plasticity. It contributes to learning and memory through use-dependent changes in synaptic efficacy and plays a role in the formation and function of the cytoskeleton. Glutamine via glutamate is converted to alpha-ketoglutarate, an important component of the citric acid cycle. It is a component of the antioxidant glutathione and of the polyglutamated folic acid. The cyclization of glutamate produces proline, an amino acid important for synthesis of collagen and connective tissue.

Glutamine Research Update
Oral glutamine supplementation decreases resting energy expenditure in children and adolescents with sickle cell anemia.
J Pediatr Hematol Oncol. 2004 Oct;26(10):619-25.
To determine the effects of orally administered glutamine on the resting energy expenditure (REE) and nutritional status of children and adolescents with sickle cell anemia. Twenty-seven children and adolescents (13 boys, 14 girls), 5.2 to 17.9 years old, received orally administered glutamine (600 mg/kg per day) for 24 weeks. Measures of REE and other nutritional parameters were compared at baseline and 24 weeks. RESULTS: After 24 weeks, the patients' median REE (kcal/d) decreased by 6%. Patients with less than 90% ideal body weight had even greater declines in REE after 24 weeks. Improvements in nutrition parameters and in two amino acids in the plasma were observed. CONCLUSIONS: After 24 weeks of orally administered glutamine, children and adolescents with sickle cell anemia had a decrease in REE and improvement in nutritional parameters. Those who were underweight had a greater decrease in REE than those of normal body weight. Lowering REE may be an effective way to improve the growth of these children and adolescents.

Effects of an oral mixture containing glycine, glutamine and niacin on memory, HGH and IGF-I secretion in middle-aged and elderly subjects.
Nutr Neurosci. 2003 Oct;6(5):269-75.
Aging is associated with declining activity of the growth hormone-insulin-like growth factor-I (GH-IGF-I) axis and with a decrease in cognitive function. The stimulatory effect of an orally administered nutritional supplement, mainly containing glycine, glutamine and niacin on the GH-IGF-I axis and on mood and cognition was investigated. Forty-two healthy subjects (14 men and 28 women, aged 40-76 years) were enrolled in a randomised, double blind, placebo-controlled trial. They received 5 g of a nutritional supplement or placebo, twice daily orally for a period of 3 weeks. At baseline and after 3 weeks, blood was collected for measurement of serum GH and IGF-I levels and mood and cognitive function were tested. The nutritional supplement ingestion for 3 weeks was found to increase serum GH levels with 70% relatively to placebo, whereas circulating IGF-I levels did not change. Mean GH (+/- SD) increased in this group from 3.23 (+/- 4.78) to 4.67 mU/l (+/- 5.27) (p = 0.03). GH increase was not associated with improvement in mood or memory. Correlation analyses, however, revealed that individual increases in IGF-I, but not GH, were associated with improved memory and vigour. It is concluded that an oral mixture of glycine, glutamine and niacin can enhance GH secretion in healthy middle-aged and elderly subjects.

L-glutamine supplementation improves nelfinavir-associated diarrhea in HIV-infected individuals.
HIV Clin Trials. 2003 Sep-Oct;4(5):324-9.
PURPOSE: To determine whether L-glutamine decreases the severity of nelfinavir-associated diarrhea in HIV-infected individuals. Other endpoints include the effect on quality of life, muscle-wasting syndrome, CD4 counts, and viral load. METHOD: HIV-infected patients with nelfinavir-associated diarrhea for >1 month were randomized to receive L-glutamine 30 g/day or placebo for 10 days in a prospective, double-blind, crossover study. Diarrhea was measured on a scale ranging from grade 0 (no diarrhea) to grade 4 (severe diarrhea, > 7 stools/day). Quality of life was assessed by the Medical Outcome Study (MOS) HIV questionnaire. RESULTS: Twenty-five participants completed the study. There was a significant difference between the L-glutamine and placebo arms on the mean grade of diarrhea (0.762 vs. 1.850, p <.01) when placebo was administered first. When L-glutamine was administered first, there was a significant crossover effect (p <.02), with similar mean grades of diarrhea in the two groups. There was also a significant difference between L-glutamine and placebo in the mean change in MOS scores from baseline (1.48 vs. -2.19, p <.017). There were no significant differences between treatment groups for the other endpoints. CONCLUSIONS: In this population of HIV-positive participants, L-glutamine 30 g/day significantly (p <.01) reduced the severity of nelfinavir-associated diarrhea and produced improved quality of life compared with placebo.

The effects of 8 weeks of creatine monohydrate and glutamine supplementation on body composition and performance measures.
Lehmkuhl M, Malone M. Auburn University, Auburn, AL 36849, USA.
J Strength Cond Res. 2003 Aug;17(3):425-38.
Twenty-nine (17 men, 12 women) collegiate track and field athletes were randomly divided into a creatine monohydrate (CM, n = 10) group, creatine monohydrate and glutamine (CG, n = 10) group, or placebo (P, n = 9) group. The CM group received 0.3 g creatine.kg body mass per day for 1 week, followed by 0.03 g creatine.kg body mass per day for 7 weeks. The CG group received the same creatine dosage scheme as the CM group plus 4 g glutamine /day (-1). All 3 treatment groups participated in an identical periodized strength and conditioning program during preseason training. Body composition, vertical jump, and cycle performances were tested before (T1) and after (T2) the 8-week supplementation period. Body mass and lean body mass (LBM) increased at a greater rate for the CM and Creatine-Glutamine groups, compared with the P treatment. Additionally, the CM and CG groups exhibited significantly greater improvement in initial rate of power production, compared with the placebo treatment. These results suggest CM and creatine-glutamine significantly increase body mass, LBM, and initial rate of power production during multiple cycle ergometer bouts.

Glutamine metabolism by lymphocytes, macrophages, and neutrophils: its importance in health and disease.
J Nutr Biochem. 1999 Jun;10(6):316-24.
Many aspects of the cell biology of lymphocytes, macrophages, and neutrophils have been studied extensively. Our recent work on these cells has investigated how fuel metabolism, especially glutamine metabolism, is related to the specific function of these cells in the inflammatory response. The high rate of glutamine utilization and its metabolism in such immune cells has raised the question of why glutamine is responsible for these functions. The macrophage has access to a variety of metabolic fuels both in vivo and in vitro. The quantitatively important role of glutamine in the processes of free radical and cytokine production has been established in our laboratories. Our current understanding of the rate of utilization and the pathway of metabolism of glutamine by cells of the immune system raises some intriguing questions concerning therapeutic manipulation of utilization of this amino acid, specifically the phagocytic and secretory capacities of cells of the defense system can be beneficially altered.

The influence of combined supplementation of glutamine and recombinant human growth hormone on the protein metabolism in severely burned patients
Zhonghua Shao Shang Za Zhi. 2004 Aug;20(4):220-2.
To investigate the influence of combined supplementation of glutamine and recombinant human growth hormone on the protein metabolism in severely burned patients. METHODS: Sixty severely burned patients were enrolled in the study and were randomly divided into control (C, n = 20) and glutamine with rhGH (glutamine + rhGH, n = 20) groups. The patients in C group received glycin as the placebo, while those in Gln group took Gln orally in dose of 0.5 g kg(-1) d(-1) during 1-14 postburn days (PBDs). For the patients in glutamine + rhGH group rhGH was administered subcutaneously in dose of 0.2 U kg(-1) d(-1) in addition to glutamine in same dosage beginning on the 7 PBD for 7 days. The plasma glutamine concentration in the 3 groups of patients was determined on the 1st, 7th and 14th PBD and the plasma albumin level was determined on 14th and 21st PBD. The wound healing rate of the patients within 30 PBSs and the total hospital stay days were recorded. RESULTS: The plasma glutamine concentration in glutamine + rhGH group of patients was evidently higher than that in C group after 7 PBD. The plasma albumin level in glutamine + rhGH group was obviously higher than that in C and glutamine groups on the 21st PBD. The wound healing rate in glutamine + rhGH group was evidently higher than that in glutamine and C groups on the 30th PBD (P < 0.05). The total hospital stay days in glutamine + rhGH group were obviously less than that in C and glutamine groups. CONCLUSION: Combined administration of glutamine and rhGH could be beneficial to the elevation of plasma glutamine level in severely burned patients and the systemic protein synthesis was therefore enhanced and the wound healing rate was improved.

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Sitosterol
Stinging Nettle extract

Glutamine Questions
Q. hi. very informative site. the page on glutamine states that there are no side effects of glutamine except in high doses. i learned that glutamine
converts to glutamate, the major excitatory neurotransmitter. have you heard that there could be dangers of taking glutamine because of the risk for the neurotoxicity of glutamate? i was just wondering if you have heard of such a thing and what you're thoughts on it are. personally i have found creatine to be much more effective for muscle gains and i have noticed stimulating effects when trying glutamine.
   A. Perhaps we should have clarified that there are not short term known glutamine side effects. As to long term daily use of glutamine in high doses, we really don't know what potential danger, if any, it would have.

Q. How is L-Alanyl-L-Glutamine Dipeptide different than glutamine in a practical sense? I have seen ads fof L-Alanyl-L-Glutamine Dipeptide in a muscle magazine.
   A. I have not seen any studies comparing L-Alanyl-L-Glutamine Dipeptide to glutamine itself, so not much can be said at this time.