What is Glutamine? Benefits and Uses Explained

Glutamine is the most abundant amino acid in the human body. This compound plays vital roles in protein synthesis, immune function and gut health. The body just needs more glutamine during stress, injury or illness than it can naturally produce, even though muscles make about 90% of all glutamine.

What is glutamine exactly? This conditionally essential amino acid serves as the main fuel source for immune cells, especially white blood cells. Glutamine’s benefits go beyond immune support. The compound helps create nucleotides and non-essential amino acids, which makes it crucial for cellular metabolism. Research shows that glutamine supplements can help patients recover faster after surgery, get fewer infections and leave the hospital sooner.

What is Glutamine and Why is it Important?

Glutamine is a vital building block for proteins in the human body. It helps with protein synthesis, acid-base balance regulation, and moves nitrogen between tissues. Your body uses glutamine as the preferred fuel source for cells that divide faster, like enterocytes (intestinal cells) and lymphocytes (immune cells) [1].

L-glutamine vs D-glutamine

You’ll find glutamine in two forms that have slightly different molecular arrangements: L-glutamine and D-glutamine. The “L” in L-glutamine means “levo,” which points to the left-handed orientation of the molecule [2]. These forms might look similar, but they work quite differently in your body:

• L-glutamine is the active form you’ll find in foods and supplements. Your body makes and uses this form naturally. Products like L-Glutamine Powder by Pure Encapsulations or L-Glutamine Capsules by Nutri Advanced use this biologically active form.
• D-glutamine rarely present in nature and barely works in humans. It doesn’t play any important role in human physiology [2].

Scientists and nutritionists usually mean L-glutamine when they talk about “glutamine” since it’s the form that matters for human health. This means products like L-Glutamine Powder by Lamberts or L-Glutamine Capsules by Klaire Labs give you the form your body naturally uses.

How the body produces glutamine

Your body makes glutamine through a process that uses the enzyme glutamine synthetase. This enzyme turns glutamic acid and ammonia into glutamine [2]. Here’s what you should know about glutamine production:

• A healthy 70 kg person has about 70-80 g of glutamine throughout their body [3].  
• Your body makes about 40-80 g of glutamine each day [3][3].
• Skeletal muscle, lungs, fat tissue, and sometimes the liver make most of your glutamine [4].  
• Skeletal muscles do the heavy lifting by making about 90% of your body’s glutamine.

Glutamine moves into your bloodstream and makes up about 20% of all free amino acids in plasma. Blood levels usually sit between 500-800 μmol/L after fasting for 12 hours [3]. This makes it the most common amino acid in your blood [4].

Top Benefits of Glutamine for the Body

Glutamine provides many advantages beyond being a protein building block. This versatile amino acid helps multiple bodily functions that boost your overall health and wellbeing.

Supports immune function

Glutamine works as the main fuel source for immune cells, and these cells use it as much as or more than glucose [10]. White blood cells, including lymphocytes, need glutamine to multiply and produce cytokines [10]. Scientists often call it “the fuel of the immune system” [2].

Your body’s glutamine levels can drop when you’re sick or injured because your need for glutamine becomes higher than what your body can produce [10][7].

Promotes gut and intestinal health

Your intestines make up much of your immune system, with countless immune cells and trillions of good bacteria [7]. Glutamine is a vital part of keeping your intestinal lining healthy [11].

Studies prove that glutamine strengthens your gut wall and might reduce intestinal permeability or “leaky gut” [11]. Patients who took glutamine supplements showed less intestinal permeability when measured by the lactulose/mannitol ratio [12]. The supplements also helped protect intestinal cells from toxin damage [13].

L-Glutamine Capsules by Nutri Advanced might help if you need gut support.

Helps reduce muscle soreness post-exercise

While glutamine supplements haven’t always shown muscle gain or performance benefits [7], they might help you recover after exercise. Studies show that taking glutamine can reduce muscle soreness and damage markers after intense workouts [3].

Research found that individuals who took glutamine had lower levels of creatine kinase (CK) and myoglobin compared to those who took a placebo, which means less muscle damage [3]. Athletes looking to reduce post-workout soreness might benefit from L-Glutamine  before exercise works best, as it keeps physiological levels steady during your workout [3]. The evidence about athletic performance improvement remains mixed [11].

May aid in recovery after surgery or illness

Your body needs more glutamine after surgery or serious illness. Six randomised blind trials showed that patients who took glutamine supplementation spent less time in the hospital [14]. These supplements also helped critically ill patients survive better and reduced their medical costs [7].

Glutamine supplements helped patients with blunt trauma by increasing plasma levels, reducing immunosuppression, [14].

Common Uses of Glutamine Supplements

Glutamine supplements have become popular in health circles of all types due to their many uses. Research shows that healthcare practitioners and individuals are finding new ways to use this amino acid beyond basic nutrition.

Athletic performance and recovery

Athletes have used glutamine supplements for years to help them recover better. When endurance exercise lasts more than two hours, muscle glutamine levels drop [15]. This drop can weaken immune function and slow recovery. Taking supplements helps bring these levels back up and might lower post-exercise ammonia in the blood [15].

In spite of that, research on performance benefits isn’t clear cut. A detailed meta-analysis shows that glutamine supplements don’t really affect athletic immune function or aerobic performance [16]. The research did reveal something interesting – glutamine supplements led to better weight loss [16]. They also reduced neutrophil numbers when doses were higher than 200 mg/kg body weight [16].

Support during illness or trauma

Glutamine becomes vital when someone is seriously ill, injured, or recovering from surgery. The body just needs more glutamine than it can make during these stressful times [1]. Studies show that giving glutamine to critically ill patients through IV has helped them survive better, get fewer infections, cost less to treat, and leave the hospital sooner [6].

Medical use in sickle cell disease

Glutamine is approved as a prescription treatment (Endari) for sickle cell disease patients aged 5 and older [17]. Clinical trials showed several key benefits:

• Fewer sickle cell crises (median of 3 versus 4 for placebo) [17]
• Reduced hospital visits due to sickle cell pain [17]
• Shorter total hospital stays [17]
• Lower rates of acute chest syndrome [17]

A 48-week randomised trial showed that L-glutamine therapy helped patients go longer without pain crises – 84 days compared to 54 days with placebo [18].

When glutamine becomes conditionally essential

Glutamine usually isn’t an essential amino acid, but it can become “conditionally essential” in some cases [5]. This happens when:

• Your body just needs more than it can make [1].
• You’re facing severe illness, injury, surgery, or intense exercise [6].  
• You have conditions like cancer, sepsis, infections, or trauma [3].

These stressful situations can drop your plasma glutamine from normal levels of 600-800 μmol/L down to 300-400 μmol/L [3]. Your body tries to fix this by breaking down muscle tissue to release more glutamine. Without help, this can lead to muscle wasting [2].

If you have these conditions, taking glutamine supplements like L-Glutamine Powder by New Roots Herbal might help meet your increased needs and support recovery.

Your body usually makes enough glutamine for normal function. But some conditions create a bigger need for this versatile amino acid. You might need extra from your diet or supplements.

Where is Glutamine Found in the Diet?

Getting enough glutamine in your diet means choosing foods packed with this versatile amino acid. You’ll typically get 3 to 6 grammes of glutamine daily through regular meals, though these changes based on what you eat [7]. The good news is glutamine is available in many food sources, making it easy to boost your intake naturally.

Animal-based sources

Animal proteins pack a powerful glutamine punch thanks to their high protein content. Meats like beef, chicken, and turkey are excellent sources if you want to support muscle recovery and immune function. A 100-gramme serving of beef gives you about 1.2 grammes of glutamine, which makes up 4.8% of its total protein content [7].

Seafood serves as another great glutamine source. Wild-caught fish usually has more glutamine than freshwater varieties. Fatty fish like salmon, mackerel, and tuna are rich in this amino acid. Additionally, shellfish like shrimp, crab, and lobster pack substantial glutamine amounts.

Dairy products and eggs complete the animal-based glutamine sources. Skim milk protein contains about 8.1% glutamine [7]. Greek yoghurt and cottage cheese give you both glutamine and probiotics, which helps your gut health. Each large egg provides about 0.6-0.8 grammes of glutamine [8], mostly in the whites.

Plant-based sources

In stark comparison to this, plant foods also pack significant glutamine, though usually less than animal products. Legumes shine as top plant sources, with lentils giving you about 3 grammes of glutamine per 100 grammes [8]. Kidney beans, chickpeas, and soybeans also add meaningful amounts.

Tofu and tempeh come from soybeans and provide about 0.5-0.6 grammes of glutamine per 100 grammes [8]. These options are great protein sources if you follow vegetarian or vegan diets.

Nuts and seeds are glutamine powerhouses too. To cite an instance, almonds give you roughly 2 grammes per 100- gramme serving [8]. Sunflower seeds, walnuts, and cashews help boost your glutamine intake while providing healthy fats and other nutrients.

Cabbage (especially cooked) and leafy greens like spinach stand out as surprisingly rich glutamine sources. Some grains contain glutamine too – white rice protein has about 11.1% glutamine while corn protein packs an impressive 16.2% glutamine [7].

Plant-based diet followers can try supplement like  L-Glutamine Capsules by Klaire Labs to complement their food sources.

How much glutamine is in common foods

Different foods contain varying amounts of glutamine. Research using advanced lab techniques shows glutamine makes up between 4.4% of protein in eggs to 16.2% in corn [7].

Here’s what you’ll find in common foods:

• Beef: 4.8% of protein (about 1.2g per 100g)  
• Eggs: 4.4% of protein (about 0.6g per 100g)
• Skim milk: 8.1% of protein (roughly 0.3g per 100g)  
• Tofu: 9.1% of protein (about 0.6g per 100g)
• White rice: 11.1% of protein (about 0.3g per 100g)  
• Corn: 16.2% of protein (roughly 0.4g per 100g) [7]

Some plant foods like corn and rice have higher glutamine percentages in their protein. Their lower overall protein content means you’ll get less total glutamine compared to animal sources [7].

Regular diets get glutamine from various sources: grains provide about 32%, dairy products give 16%, and fish/poultry deliver roughly 13% [9]. If you can’t meet your glutamine needs through food alone, L-Glutamine  supplements offer concentrated alternatives.

Is Glutamine Safe? Dosage and Side Effects

Understanding L-glutamine’s safety profile and proper dosages becomes crucial if you’re thinking about supplementation. Research has extensively studied glutamine, which gives us reliable information about its proper use.

Recommended daily intake

Individual circumstances and health conditions determine daily glutamine requirements. General supplementation typically needs 5-30 grammes daily [19]. Research focusing on muscle recovery has used approximately 0.1g per kg of body weight daily [20].

A typical diet naturally gives you 3-6 grammes of glutamine daily [7]. This serves as a useful baseline to think over supplementation needs. Products like  L-Glutamine Capsules by Nutri Advanced usually contain 5 grammes per serving that line up with research-backed amounts.

Medical applications such as sickle cell disease need weight-dependent dosages:  

• Children over 5 years weighing under 30kg: 5g twice daily [21]
• Those weighing 30-65kg: 10g twice daily [21]
• Individuals over 65kg: 15g twice daily [21]

Short-term vs long-term use

Short-term glutamine supplementation tolerates doses up to 40 grammes daily well [4]. Studies have used approximately 45 grammes daily for six weeks without negative side effects [7].  

Long-term supplementation needs more research. Studies note that “more information is needed concerning long-term supplementation, especially when you have high doses” [7]. Glutamine’s effects on amino acid absorption and processing during extended use lack proper documentation [7].

Who should avoid glutamine supplements

These groups should exercise caution or avoid glutamine supplements completely:

Medical contraindications:

• Individuals with liver disease (risk of brain function issues) [4][20]
• Those with kidney disease/renal impairment [20]
• Individuals with Reye syndrome [20]
• Individuals with bipolar disorder (risk of mania/hypomania) [4]
• Those with MSG sensitivity (as the body converts glutamine to glutamate) [4]
• Individuals prone to seizures [4][22]

Pregnant or breastfeeding women’s healthcare providers should approve supplementation since research remains limited in these groups [4][22].

Common side effects include bloating, nausea, dizziness, heartburn, and stomach pain [4][22]. Serious reactions like chest pain, confusion, or skin rash need immediate medical attention [9].

Conclusion

This piece explored glutamine’s remarkable versatility as the most abundant amino acid in our body. Of course, it plays vital roles in protein synthesis, immune function, and gut health that make it essential for our physiological processes. The body usually makes enough glutamine under normal conditions, but it becomes conditionally essential during stress, illness, or intense physical activity.

You can get glutamine from various food sources. Animal products like beef, poultry, and dairy pack substantial amounts. Plant-based options such as legumes, nuts, and certain vegetables work great for vegetarians and vegans. In spite of that, supplementation might help individuals who face increased physiological demands.

Glutamine’s benefits go way beyond simple nutrition. It powers immune cells and supports their growth and function. Additionally, it makes the intestinal lining stronger and might reduce problems with intestinal permeability. Research shows its value in recovery after surgery or illness – patients often leave hospitals sooner and get better results. While evidence about athletic performance remains mixed, glutamine supplements like L-Glutamine Powder by Pure Encapsulations or L-Glutamine Capsules by Nutri Advanced might help reduce muscle soreness after exercise.

Glutamine is approved as a prescription treatment (Endari) for sickle cell disease, which shows its therapeutic potential.

Most individuals tolerate glutamine supplements well at doses between 5-30 grammes daily. But individuals with liver or kidney disease, bipolar disorder, or MSG sensitivity should be careful. You should talk to healthcare providers before starting supplements.

Glutamine supplements are widely available, but you should think over your approach carefully.

Glutamine ended up showing how one amino acid can deeply affect many body systems. Whether you get it through food or supplements, this versatile compound proves its worth in maintaining daily health and treating specific medical conditions.

FAQs

References

https://link.springer.com/10.1007/978-1-4614-7836-2_141
https://www.womenshealthmag.com/uk/food/a46501304/l-glutamine-benefits/
https://pmc.ncbi.nlm.nih.gov/articles/PMC8234492/
https://www.webmd.com/vitamins/ai/ingredientmono-878/glutamine
https://www.sciencedirect.com/science/article/pii/S0022316622146006
https://pubmed.ncbi.nlm.nih.gov/23362887/
https://www.healthline.com/nutrition/glutamine
https://www.geneticnutrition.in/blogs/genetic-life/foods-rich-in-glutamine-natural-sources-to-include-in-your-diet? srsltid=AfmBOoqiehXsmyPjjt2zkN-hB1Ql3hNanyleEjL879SRmIkudf7pXsZt
https://www.drugs.com/sfx/glutamine-side-effects.html
https://pubmed.ncbi.nlm.nih.gov/30360490/
https://www.webmd.com/diet/health-benefits-glutamine
https://pmc.ncbi.nlm.nih.gov/articles/PMC8399682/
https://pmc.ncbi.nlm.nih.gov/articles/PMC5454963/
https://pubmed.ncbi.nlm.nih.gov/11533310/
https://www.scienceinsport.com/sports-nutrition/l-glutamine-explained-sis/
https://pubmed.ncbi.nlm.nih.gov/29784526/
https://pmc.ncbi.nlm.nih.gov/articles/PMC8399682/
https://www.nejm.org/doi/full/10.1056/NEJMoa1715971
https://examine.com/supplements/glutamine/? srsltid=AfmBOoo4BJ2_Hlcod6q72FZJE1P0JOOEXSeiyjeREr2tX4D8bFs1SjaI
https://www.hollandandbarrett.com/the-health-hub/vitamins-and-supplements/amino-acids/what-is-glutamine/
https://www.pediatriconcall.com/drugs/glutamine/160
https://www.verywellfit.com/l-glutamine-89469
https://my.clevelandclinic.org/health/articles/glutamine