L glutamine how does it work

Second, a wide variety of dose, time, and mode of supplementation was used. Dose of glutamine used in the studies varied up to 5-fold [ , , ], and treatment period varied from 2 days [ ] to 8 weeks [ ]. As glutamine couples with alanine and glycine, glutamine complex with alanine and glycine is less susceptible to degradation than free glutamine.

Many studies used glutamine-containing dipeptides, which might affect the discrepancy of outcomes. Third, a wide range of clinical courses of patients was used in the studies. Short-term glutamine administration during a flare-up phase could give a greater impact on outcomes than other phases.

Additionally, a relatively small sample size showed greater efficacy of glutamine supplementation in critically ill patients [ , , ] and in IBD patients [ , ]. Therefore, a well-controlled clinical trial with a sufficiently sized population would be required to determine the efficacy of glutamine supplementation in intestinal diseases. Although significant progress has been made in uncovering the functions of glutamine, most of these are based on observational studies. Therefore, future research should focus on the mechanisms underlying glutamine actions.

Additionally, current data from clinical trials do not support the use of glutamine supplementation in patients with intestinal diseases, despite in vitro and animal model studies having shown significant beneficial effects. Thus, future human studies should be more standardized to increase their power. Min-Hyun Kim performed the comprehensive literature search and wrote the paper. Hyeyoung Kim performed the initial literature search as well as revised and edited the paper.

All authors agree with the edited version. National Center for Biotechnology Information , U. Int J Mol Sci. Published online May Marica Bakovic, Academic Editor. Author information Article notes Copyright and License information Disclaimer. Received Mar 25; Accepted May This article has been cited by other articles in PMC.

Abstract Glutamine, the most abundant free amino acid in the human body, is a major substrate utilized by intestinal cells. Keywords: glutamine, intestinal function, inflammatory bowel disease, short bowel syndrome, nutritional therapy. Introduction Glutamine is the most abundant amino acid in human blood, skeletal muscle, and the free amino acid pool [ 1 ].

Roles of Glutamine in the Intestine 2. Tissue Integrity The mammalian intestinal lumen is lined with a single layer of epithelial cells [ 26 ]. Open in a separate window. Figure 1. Apoptosis and Cellular Stresses As intestinal epithelial cells have a turnover rate of four to five days, it is critical for these cells to maintain a fine balance between proliferation and apoptosis for normal function [ 76 ].

Clinical Implications for Intestinal Diseases Given the importance of glutamine in maintaining normal cellular functions, as discussed above, it is not surprising that glutamine supplementation has been considered and examined in the clinical setting, particularly in diseases implying impaired glutamine metabolism.

Author Contributions Min-Hyun Kim performed the comprehensive literature search and wrote the paper. Conflicts of Interest The authors declare no conflict of interest. References 1. Calder P. Glutamine and the immune system. Albrecht J. Roles of glutamine in neurotransmission. Glia Biol. Amores-Sanchez M. Glutamine, as a precursor of glutathione, and oxidative stress. Coster J. Glutamine: Metabolism and application in nutrition support. Asia Pac. Patience J. A review of the role of acid-base balance in amino acid nutrition.

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Author Contributions V. Funding We thank the Department of Health Science, Torrens University, and the Curtin School of Pharmacy and Biomedical Sciences for financial research support and excellent research facilities, respectively.

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Due to its role as a building block of protein, some researchers have tested whether taking glutamine as a supplement improves muscle gain or exercise performance. In one study, 31 people took either glutamine or a placebo during six weeks of weight training By the end of the study, both groups showed improved muscle mass and strength. However, there were no differences between the two groups.

Additional studies have also shown that it has no effects on muscle mass or performance 30 , However, some research has reported that glutamine supplements may decrease muscle soreness and improve recovery after intense exercise In fact, one study found that glutamine or glutamine plus carbohydrates can help reduce a blood marker of fatigue during two hours of running It has also been used to try to boost the immune function of athletes, but results vary 34 , 35 , Other research has found that it did not improve the recovery of carbohydrate stores glycogen in muscle when added to carbohydrates and certain amino acids In the end, there is no evidence that these supplements provide benefits for muscle gain or strength.

There is some limited support for other effects, but more research is needed. It has been estimated that a typical diet may contain 3 to 6 grams per day, although this amount could vary based on the types and quantities of foods consumed Studies on glutamine supplements have used a wide variety of doses, ranging from around 5 grams per day up to high doses of approximately 45 grams per day for six weeks Although no negative side effects were reported with this high dosage, blood safety markers were not specifically examined.

Other studies have reported minimal safety concerns regarding short-term supplementation of up to 14 grams per day Overall, it is believed that the short-term use of supplements is likely safe. However, some scientists have raised concerns about their sustained use Adding glutamine to a regular diet may cause a variety of changes in the way the body absorbs and processes amino acids.

Yet, the long-term effects of these changes are unknown Therefore, more information is needed concerning long-term supplementation, particularly when high doses are used. It is possible that glutamine supplements may not have the same effects if you eat an animal-based, high-protein diet, compared to a plant-based, lower-protein diet. If you follow a plant-based diet with low glutamine content, you may be able to consume supplements while still receiving a normal daily amount of it overall.

If you decide to take a glutamine supplement, it is probably best to start with a conservative dose of around 5 grams per day. L-glutamine is the important form, which is produced naturally in the body and found in many foods. It is estimated that a typical diet contains 3 to 6 grams per day. It provides fuel for immune and intestinal cells and helps keep the connections in the intestines strong.

During times when your body cannot produce optimal amounts, such as during injury or severe illness, supplementing with it may be beneficial for your immune health and recovery. Glutamine is also frequently used a sports supplement, but most research does not support its effectiveness.

Supplementing appears to be safe in the short-term, but more research is needed on its long-term effects. Before taking a glutamine supplement, consider whether the reason for taking it is supported by current evidence. There are several dietary supplements that can help increase muscle mass and strength. Here are the 6 best supplements to gain more muscle. Testosterone is crucial for many body processes, including fat loss and muscle growth. Here are 8 of the best testosterone boosting supplements.

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