What is glutamine? Effects and dosage

Glutamine is one of the most important amino acids in the human body, essential for the proper functioning of many systems, including the muscular, immune and digestive systems. Although often associated with the world of sport and supplementation, its role goes far beyond muscle building. In this article, you will learn what glutamine is, how it is produced, what health benefits it has and who can benefit from it.

1. Glutamine – what is it?
2. How is glutamine produced and where does it come from?
3. The effects of glutamine – what are its health benefits?
4. Who can benefit from glutamine supplementation?
5. How to dose glutamine
6. Is glutamine safe?
7. When should glutamine be used?
8. Summary – is glutamine worth taking?

Glutamine – what is it?

History and discovery

Glutamine was discovered in 1883 by Ernst Schulze. It is an endogenous amino acid, which means that the body can synthesise it on its own. Under certain conditions, such as intense physical exertion, stress, infections or injuries, the demand for glutamine may exceed the body's ability to produce it, making it a conditionally essential amino acid.

What is glutamine?

Glutamine is an amino acid belonging to the group of polar amino acids. It occurs in the body in two forms:

• L-glutamine – a biologically active form, responsible for most functions in the body.
• D-glutamine – a less common form with no biological significance.

Glutamine accounts for approximately 60% of the free amino acid pool in skeletal muscles, making it the most abundant amino acid in the human body.

How is glutamine produced and where does it come from?

Synthesis in the body

Glutamine is synthesised mainly in skeletal muscles, but also in the lungs, brain and intestines. This process involves the conversion of glutamate with the help of the enzyme glutamine synthetase and ammonia.

Sources of glutamine in the diet

Glutamine is present in many foods:

• Protein-rich foods: meat, fish, eggs, dairy products.
• Plant-based foods: legumes (soya, lentils), spinach, beetroot, cabbage, nuts.

Obtaining glutamine as a supplement

Glutamine in supplements is produced through bacterial fermentation involving lactic acid-producing bacteria or through chemical synthesis.

The effects of glutamine – what are its health benefits?

Supports muscle recovery

Glutamine is essential for muscle recovery after training. After intense physical exertion, glutamine levels in the body drop, which can lead to fatigue and reduced performance.

Effects for athletes:

• Accelerates recovery after exercise.
• Reduction of muscle damage.
• Increased muscle protein synthesis.

Supporting the immune system

Glutamine is fuel for immune system cells such as lymphocytes and macrophages. In states of physical stress (e.g. illness, physical exertion), the demand for glutamine increases rapidly.

Benefits:

• Strengthens immunity.
• Reduces the risk of infection, especially in endurance athletes.

Protects the digestive tract

Glutamine supports intestinal health by providing the main source of energy for enterocytes – cells lining the intestines. It also protects the mucous membrane of the digestive tract.

Benefits:

• Improved intestinal barrier function.
• Reduction of irritable bowel syndrome (IBS) symptoms.
• Alleviation of Crohn's disease symptoms.

4. Supporting brain health

Glutamine is a precursor to neurotransmitters such as glutamate and GABA, which regulate cognitive function and mood.

Benefits:

• Improved concentration.
• Reduced stress symptoms and improved mood.

Anti-catabolic effect

Glutamine prevents the breakdown of muscle proteins in catabolic states such as fasting, intense training or illness.

Who can benefit from glutamine supplementation?

Athletes

Glutamine is particularly recommended for physically active people, especially those who train for endurance and strength. Intense physical exertion causes a decrease in glutamine levels in the body, which can lead to weakened muscle regeneration and reduced immunity. Supplementation helps speed up regeneration, reduce the risk of infection and support physical performance.

People with intestinal problems

Glutamine is known for its positive effect on intestinal health. It can be particularly helpful for people suffering from irritable bowel syndrome (IBS) or leaky gut, as it supports the regeneration of the intestinal mucosa. It is an amino acid that acts as a source of energy for intestinal cells, helping to restore their integrity and improving the functioning of the digestive tract.

Post-operative patients

Glutamine is also recommended for people who have undergone surgery, as it supports wound healing and regeneration of the body. The use of glutamine after surgery can contribute to a faster recovery and reduce the risk of infection, which is particularly important during convalescence.

People with weakened immune systems

If the body is struggling with weakened immunity, for example during convalescence after an illness, glutamine can be helpful. It supports the functions of the immune system by increasing the production of immune cells, which helps to fight infections faster and improve the body's overall immunity.

People exposed to chronic stress

Prolonged stress can lead to a weakened immune system, concentration problems and reduced cognitive function. Glutamine helps regulate cortisol (stress hormone) levels and supports the nervous system, improving mental resilience and overall regeneration of the body in difficult conditions.

How to dose glutamine

Is glutamine safe?

Glutamine is considered one of the safest supplements available on the market. It is well tolerated by most people, even with regular use. Its natural presence in the body as a key amino acid means that glutamine supplementation does not cause adverse reactions at standard doses (up to 20 g per day). This makes glutamine a popular choice among athletes and people who care about their gut health and immunity.

When should glutamine be used?