What is L-Glutamine?
L-Glutamine is an amino acid produced in the human body. It makes up approximately 60 percent of the skeletal system and is found in substantial amounts in the muscles as well. It is one of the 20 amino acids that make up the standard human genetic code. Although it is not regarded as an essential amino acid, it has several medical uses and is associated with a significant number of health benefits.
On its own, L-glutamine is a dry powder at room temperature, easily dissolved in water or other liquids. This makes it easily put in capsule form for a stand-alone supplement or added to other amino acids and nutrients as part of a shake mix.
The L in L-glutamine is used to distinguish it from its rare isomer, D-glutamine, which has slightly different properties because of the variance in its structure. D-glutamine is found mostly in the cell walls of some bacterias and has no known use or function in more complex organisms.
L-Glutamine and its Role in the Human Body
L-Glutamine supports the function of neurotransmitters and speeds the removal of ammonia as waste. The human body is typically capable of producing enough L-Glutamine, but in certain cases, additional amounts may be necessary in the form of supplements. This is particularly true for individuals who are under physical or mental stress, or who are fighting serious illnesses. Small amounts of L-Glutamine can be stored in the lungs and muscles, but if a deficiency is present, these stores are quickly depleted.
History of L-Glutamine
Glutamine was first discovered in 1893 by Walter Schulze when he found the amino acid in beets and separated it from their juice. An attached ion ultimately creates the substance L-Glutamine, and this ion is signified by the letter “L” in the supplement’s name. The first synthetic L-Glutamine was created in a laboratory in 1935.
One of the first studies conducted on L-Glutamine involved intensive care patients. During the study, it was determined that more successful recoveries were enjoyed when patients were given extra L-Glutamine.
Since then, the athletic community developed an interest in L-Glutamine. The rationale was that if medical trauma and physical exercise both tax the human body in a similar way, then the benefits of L-Glutamine to athletes would be similar to those enjoyed by the aforementioned intensive care patients. To this day, L-Glutamine remains a staple of many athletes and other individuals during physical training.
L-Glutamine Medical Uses
Supports the Human Immune System
In certain clinical trials, particularly one conducted by the University of Maryland Medical Center, individuals reported becoming ill less often when taking L-Glutamine supplements. This indicates that the substance likely has a positive effect on the human immune system.
Stabilizes Glucose Levels
Glutamine plays an important role in the body’s synthesis of proteins and lipids, the latter of which are also simply referred to as fats. Additionally, it is used as a secondary energy source at the cellular level when glucose is not available. For this reason, when appropriate amounts of L-Glutamine are found in one’s body, he or she is more likely to maintain normal glucose levels.
Regulates Kidney Acid Levels
According to the Brazilian Journal of Medical and Biological Research, glutamine regulates acid balance in the kidneys. A certain amount of ammonia is always present in one’s renal system. Its role is to filter out impurities. However, once it has served this function, it must be turned into urea by part of the kidney called the glomerulus, after which it is entirely eliminated. L-Glutamine ensures that this function is completed efficiently. Therefore, it prevents excessive acid from building up in the person’s system, as would be the case if the ammonia is not quickly changed to urea. This breakdown of the ammonia also helps the renal system to synthesize purines, which is vital to kidney health as well.
May Cure Leaky Gut
Activated immune cells, such as the type found deep within the gut, also benefit from L-Glutamine. This is because the latter substance plays an important role in the constant building and rebuilding of the intestinal lining. However, the supplement must be taken orally for one to achieve this benefit, as when it is taken intravenously, it bypasses the intestinal tract.
L-Glutamine is also though to help this part of the body produce more mucus. Mucus is vital to the prevention of a common intestinal malady called “leaky gut syndrome,” during which the mucus the intestines need to fortify themselves leak into other areas of the GI tract.
Proven L-Glutamine Benefits
1. Counteracts General Physical Stress
Because physical stress requires many body systems to work together to repair acute damage, supplements called “adaptagens” have been developed over the years. Some experts are of the opinion that L-Glutamine may have adaptagen characteristics.
Because physical stress, even the good kind that comes from aerobic exercise, can increase the body’s level of ammonia. At high levels, ammonia is obviously toxic to the body and the person’s kidneys may not be able to keep up with these elevated levels without a bit of help. L-glutamine has a hand in reducing these levels in the kidneys, as previously explained. It is this same action that helps prevent leaky gut syndrome, but also aids in full system recovery.
This is true whether one is under mental or physical strain from a negative source or simply suffering from the normal fatigue associated with rigorous exercise. Because L-Glutamine helps the body to detoxify itself, it also prevents the fatigue that comes from physical exertion.
2. Builds Muscle and Prevents Injury
Because it is an amino acid, L-Glutamine specifically helps build muscle and prevents muscle wasting. Virtually everyone knows that muscle burns more calories than fat and those with substantial amounts of muscle on their body are typically healthier than those who carry excess fat and have poor muscle tone.
If L-Glutamine is lacking, muscle wasting can occur or muscles can take an excessively long time to rebuild themselves after exercise. Studies have shown that supplementing with L-Glutamine can prevent injuries by helping the body to quickly repair its muscles.
3. Improved Memory and Concentration
L-Glutamine is a precursor to certain amino acids that serve the brain and nervous system. This is likely why studies show a direct connection between the use of L-Glutamine supplements and a good memory and enhanced ability to focus.
Studies show that substantial stores of L-Glutamine and its byproducts in the body help the brain and nervous system handle stress more efficiently.
This not only enhances mental performance, but helps individuals avoid fatigue after long hours of working or studying. Additional research is still necessary to come to a definitive conclusion, but preliminary studies are positive.
4. Combats Insomnia and Encourages Restful Sleep
L-Glutamine and its precursor, Glutamine, are also essential to proper sleep. This may be because these substances reduce ammonia levels in the neural pathways and bloodstream. Studies show that falling asleep easily and getting 7 to 8 hours of restful sleep each night can improve energy levels, boost concentration and enhance memory function.
5. Counteracts Neural Degeneration Caused by Physical or Mental Stress
Research conducted at the Cleveland Clinic indicates that individuals under constant stress typically have lower L-Glutamine levels in their bloodstreams.
For this reason, additional studies are being conducted to determine L-Glutamine’s potential as a stress reducer. Preliminary studies were promising concerning L-Glutamine’s ability to counteract neural degeneration caused by mental or physical stress.
6. Diminishes Risks Associated with Radiation and Chemotherapy
A clinical trial conducted by the National Institutes of Health found that supplementing cancer patients with appropriate amount of L-Glutamine may help them experience fewer side effects of high-dose radiation and chemotherapy.
Additionally, evidence suggested that bone marrow transplant patients may benefit from the use of this supplement when administered intravenously.
7. Suppresses Sugar and Alcohol Cravings
According to a PubMed study conducted in 2011, L-Glutamine enhances the production of a specific beta endorphin and a unique peptide, GHG.
The study concluded that cravings for sugar and alcohol consumption were suppressed during the intracerebral application of this peptide through the use of L-Glutamine.
Obviously, this benefit is advantageous to both those who drink heavily and those who constantly crave sugar.
Of course, no supplement by itself can stop weight or alcohol problems, but these findings are significant regarding L-Glutamine’s supportive role in helping individuals to curb such cravings.
8. Improves Gastrointestinal Health
L-Glutamine helps the pH balance of the intestinal tract and balances the production of mucus. This leads to regular, healthy bowel movements and repair of both the large and small intestines.
Because a healthy GI tract may play a role in a properly functioning immune system, L-glutamine’s documented positive effects on the intestinal tract are significant regarding immune health.
Nutrition Facts & Calories of L-Glutamine
A gram of L-glutamine contains one gram of protein, zero fat, zero sugar and four calories. However, depending on the supplement’s manufacturer, additional ingredients may be added that slightly change the calorie count.
Recommended L-Glutamine Dosage
L-Glutamine easily dissolves in water or other liquids, and therefore is available in capsule or powder form. The typical recommended dose is two to five grams, divided into two equal doses taken approximately eight hours apart.
The recommended dosage for children under 12 years of age is no more than .7 grams per kilogram of weight, given once a day. There is no benefit to adults or children exceeding the recommended daily dose.
Possible L-Glutamine Side Effects
Even though L-Glutamine supplements are generally recognized as safe, extensive studies have not yet been done on long-term use of the substance. In addition, research is scanty concerning individuals who exceed the recommended dosage. However, the most common side effects reported by those using the supplement at the higher end of the dosage scale include the following:
Those who far exceed the recommended dose may experience the more serious side effects listed below:
• Personality changes
• Muscle and joint pain
• Panic attacks
Breast-feeding and pregnant women are discouraged from taking L-Glutamine, as there is no specific research that indicates whether or not the substance crosses the placenta and what effect, if any, it may have on an unborn baby.
L-Glutamine supplements should not be used by those with severe liver diseases, such as cirrhosis. Although L-Glutamine does play a role in proper liver function, taking extra amounts of the substance is thought to have a negative effect on those whose livers are already damaged. Individuals on dialysis or people who suffer from kidney disease should also avoid taking L-Glutamine unless under a doctor’s supervision.
Those who are sensitive to monosodium glutamate–MSG–may experience a similar reaction to L-Glutamine, as the latter is converted by the body to glutamate in its raw form.
Individuals suffering from bipolar disorder or any type of mania should not increase their glutamine levels through the use of supplements, as this may lead to seizures or increase the number of manic episodes they experience.
Ultimately, L-Glutamine is considered a mild, but highly effective supplement that may benefit those suffering from numerous deficiencies and ailments.
Fortunately, because it is a natural amino acid, rather than a steroid, it is not associated with the side effects and risks linked to steroid based formulas.
During times of intense physical activity, exacerbated stress or even periods of serious illness, supplementing with a high quality L-Glutamine blend may be highly beneficial.
Additionally, to enhance one’s athletic performance and effectively recover in a timely manner, L-Glutamine supplements appear to be a sound choice. Always speak to a licensed health care practitioner before using any new supplement or holistic formula.
1. Amino Acids Guide, “Glutamine,” http://www.aminoacidsguide.com/Gln.html, 2007-2016.
2. Heffley, Dr. James, Ph. D., “What is the Difference Between l-glutamine and glutamine, and the same for other amino acids?” http://www.austinchronicle.com/columns/2006-06-23/378574/. June 23, 2006.
3. Rudolf, Maximilian, “How l-glutamine Increases Memory and Cognitive Function,” http://ezinearticles.com/?How-L-Glutamine-Increases-Memory-And-Cognitive-Functions!&id=6671925. November 4, 2011.
4. Amino Acid Studies, “Amino acids and their significance for sleep, mood and performance,” http://www.aminoacid-studies.com/areas-of-use/sleep-mood-and-performance.html. 2016.