The Science of Glutamine Benefits: Strengthening Gut, Immunity, and Mind

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Glutamine is the most abundant amino acid in the body. Amino acids are the building blocks of protein, and a protein-rich diet is higher in aminos like glutamine. The gut, liver, and skeletal muscles influence glutamine circulation. 

Glutamine or L-glutamine is a non-essential amino acid because the body can produce it. However, due to its need to support many tissues throughout the body, an individual can develop deficiencies when the immune system is compromised or when they have gut issues, which decrease the absorption of vital nutrients. 

The Importance of Glutamine for the Body

Glutamine benefits almost every cell in the body, synthesizing antioxidants like nicotinamide adenine dinucleotide phosphate (NADPH). Roughly 70 to 80 g of glutamine is in an adult body, and the body produces about 40 to 80 g per day.

The liver and the intestinal lining are the primary glutamine-consuming tissues. The gut is a significant consumer of glutamine when the body is in a state of breakdown, such as with cancer, traumas, infections, and sepsis.

Glutamine is critical for the body when it is under compromise. When the breakdown of tissues occurs, there is a decrease in glutamine in these tissues, and low levels of glutamine can affect the whole body. 

Enhanced Immune Function

Glutamine supports immune cells by providing energy to neutrophils, macrophages, and lymphocytes. In immune cells, glutamine metabolism is critical in infections, cancer, and autoimmune disorders. Since glutamine levels decrease when the body is infected, supplementation can increase. Skeletal muscles are the primary producers of glutamine for the rest of the body.

When cells excessively consume glutamine or the body produces low amounts of glutamine, glutamine levels drop. Diet and supplementation are essential to bring up low levels. Immune cells have limited capability to multiply and can even result in cell death when glutamine levels are low.

Gut health is also responsible for immune function due to the digestive system’s healthy bacteria in the intestine, stomach acid, and other protective features. Reducing intestinal permeability allows the gut to fight off pathogens that lead to infection. 

Improved Digestive Health

Glutamine is essential for intestinal health, compared to the need for glucose for energy. GLS is an enzyme that breaks down glutamine into glutamate. Glutamate is an excitatory neurotransmitter. GLS aids in nutrient absorption and fighting off harmful bacteria. Individuals with gut issues have protein absorption issues and may absorb a smaller amount of glutamine than those without digestive issues.

In digestive disorders like inflammatory bowel disease (IBD), glutamine reduces inflammation. L-glutamine supplementation heals the intestinal lining, an issue with many inflammatory digestive disorders, including Leaky Gut. Additionally, it acts as an energy source for cells in the small intestine and stimulates cell growth. Glutamine reduces gut atrophy and improves intestinal permeability.

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Increased Muscle Growth and Recovery

Skeletal muscles store and produce a significant portion of glutamine in the body. To be more precise, the muscles contain roughly 80% of the body’s glutamine. Exhaustive exercise causes an inflammatory response and damage to the organs, including the liver, kidneys, and skeletal muscles. Additionally, it causes a build-up of lactic acid. Glutamine levels are depleted after exhaustive exercise. L-glutamine can reduce inflammation and organ damage and promote glycogen synthesis. Glycogen is a storage of glucose in the liver and skeletal muscles.

Insulin and insulin-like growth factors are two hormones that transport glutamine into cells, and glucocorticoids release glutamine. Glutamine and Alanine (another amino acid) are critical for muscle health. Sepsis causes glutamine levels to drop, and it causes more synthesis and release of glutamine, lowering the amount in the muscles.

Glutamine is responsible for muscle growth, gene expression, and tissue regulation. Glutamine also has protective effects, such as minimizing the effects of oxidative stress. Additionally, it supports the production of glutathione, an antioxidant that protects cells. 

Liver Support

The liver is responsible for blood detoxification, bile production, and managing carbohydrates, proteins, lipids, drugs, blood p, and storing glycogen (energy stores).

Dehydration caused by low intracellular glutamine levels can cause insulin-resistant conditions and cell shrinkage.

In non-alcoholic fatty liver disease (NAFLD), the liver accumulates excess fat. Glutamine helps slow NAFLD and supports the growth and repair of the liver. 

Brain and Cognitive Benefits

Glutamine is a precursor for multiple neurotransmitter amino acids, including the excitatory ones glutamate and aspartate, and the calming one GABA—additionally, the gut healing benefits of L-glutamine support positive mood by the increased production of serotonin. The gut produces 90% of serotonin, which makes you happy. Low levels of serotonin cause anxiety and depression.

A research study on mice showed that L-glutamine’s antioxidative properties increased other super antioxidants and weakened the risk of developing ischemic brain injury. Glutamine’s immune benefits protect pre-term baby brain development by fighting infections. 

Wound Healing

Stress increases the body’s need for nutrients. Surgeries, physical trauma, overworked muscles and joints, and cuts can cause additional stress. Cell proliferation and protein synthesis require increased protein consumption and specific amino acids, L-arginine and L-glutamine. L-arginine and L-glutamine increase Nitric Oxide (NO) levels, which assists in wound healing by collagen formation and wound contractions.

Glutamine supplementation and topical application increase wound healing from chemo and radiation. Topical glutamine supplementation reduces ulcerations and painful mucosal symptoms from chemotreatment. In addition, the antioxidative properties decrease wound healing time. 

Weight Management

In the individuals administering the glutamine study, 39 overweight individuals were given 30g of glutamine for 14 days. The study’s individuals took body weight, waist circumference, inflammatory markers, and hormone measurements. After 14 days, participants in the obese category had diminished waist circumferences. Additionally, in a rat study, glutamine showed benefits of improved insulin and reduced adiposity.

Another study recorded obese and overweight female biomarkers, including waist circumference and metabolic markers such as glycemia and insulinemia. Insulemia declined by 20% after four weeks, and body weight and waist circumference decreased. Glutamine is effective in supporting glucose metabolism along with increasing weight loss


Cancer patients have a decreased level of glutamine in their bodies due to tumors. Tumors create glutamine traps, contributing to the low levels of available glutamine. In a rat study, those with glutamine supplementation had higher glutathione levels. Additionally, there was an accelerated rate of intestinal healing from chemotherapy and radiation. Glutamine lowers CRP levels; overall, lower CRP levels reduce infection rates and support tumor necrosis. 

Glutamine Supplementation Benefits

High glutamine diet consumption and supplementation fight bacterial infections by strengthening immune cells. Additionally, it supports post-surgery recovery, injury healing, and even radiation treatment.

The NOW brand of L-glutamine is a highly beneficial supplement that supports immune function and acts as a nitrogen transporter. It promotes gut health and is non-GMO. It is highly recommended for those looking to enhance their overall well-being. It comes in a capsule form at a very affordable rate.

L-glutamine is often combined with branch-chain amino acids (BCAAs) for increased muscle recovery and reduced soreness. Glutamine is taken in capsule or powder form but can be consumed in higher doses at a more affordable rate through powder. The powder is typically tasteless and can be thrown in a smoothie or mixed in with juice. 

Recommended Glutamine Dose

A study showed that supplementing with 20-30g of L-glutamine showed no ill effects. About 24gs of L-glutamine were given to male athletes, and muscle soreness was significantly lower over 96 hours compared to the placebo. Post-exercise doses were given at hour zero, 24, 48, and 72 hours post-exercise. 

Overall, most research studies report that around 30g of glutamine supplementation per day, in addition to dietary consumption, provides a wide range of health benefits. Increasing protein intake can increase lean muscle, aid in weight loss and gut health, and obtain higher levels of L-glutamine. Consuming protein supplements such as whey protein can assist in securing glutamine.

The Benefits of Glutamine

Glutamine benefits mental and physical health and aids in healing the body. Absorption is from the diet and supplementation. Glutamine’s ability to support child brain development, wound healing, and liver support are a few of the incredible reasons glutamine supplementation is a vital nutrient. L-glutamine consumption promotes lean muscle and body mass. Consult your physician or a dietitian before consuming high amounts of L-glutamine supplements. To reap glutamine benefits, a diet rich in protein combined with glutamine supplementation and protein supplement consumption can decrease recovery time. 

This article originally appeared on Wealth of Geeks.

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  • Megan Santiago (Holistic Momma)

    Megan is the owner and founder of Holistic Momma. Her background is in the natural health industry, she obtained a B.S. in Psychology from Liberty University is currently a Clinical Mental Health Counseling Intern. She writes about natural ways to cope with your mental health and how moms can communicate with and take care of their children in a loving and effective manner.

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