What is L-glutamine and what does it do for your health?
L-glutamine is an amino acid that is abundant in your body, but you may not have heard much about it. In this blog, you will learn exactly what L-glutamine is, where it is found in your body, and when it might be beneficial to pay attention to your intake. We will guide you through the science, practical applications, and how you can obtain L-glutamine through diet or supplements.
What is L-glutamine?
L-glutamine is an amino acid – a building block of proteins – which your body can normally produce on its own. Therefore, it is known as a non-essential amino acid. In certain situations, such as intense physical exertion or illness, your body may temporarily use more L-glutamine than it can produce. In such cases, you can increase your L-glutamine intake through diet or supplements.
How does L-glutamine work in the body?
L-glutamine is primarily produced in your muscles, but also in your liver, adipose tissue, and brain. From there, it is transported through your blood to the areas where it is most needed at that moment.
What makes L-glutamine special? L-glutamine is an amino acid that is found in high concentrations in certain cells, such as:
- Intestinal cells (which renew every few days)
- Immune cells (such as lymphocytes and macrophages)
When your body is under pressure – for example, during physical stress such as intensive training or illness – the demand for L-glutamine can temporarily increase. You can then imagine that a deficiency might quickly arise.
What are the benefits of L-glutamine?
There are currently no health claims approved by Europe for L-glutamine. This means that we cannot make any statements about proven positive effects on your health. However, L-glutamine is the subject of scientific research in various contexts, including nutrition and exercise. But: more research is needed to draw firm conclusions. Do you have questions or are you unsure if it suits you? Get advice from our health coaches, online or in-store.
How to use L-glutamine and how much do you need?
L-glutamine is available as a powder or in capsules. A standard dosage is between 5 and 10 grams per day. During periods of intense physical exertion, this can be increased, for example, to 20-30 grams per day – always consult a specialist in such cases.
Tips for the best effect:
- Take on an empty stomach for optimal absorption
- For powder: dissolve in water or juice (tasteless)
- Combine with a protein-rich meal for extra effect
Note: every body is different. Start with a low dosage and gradually increase, so you can see what works for you.
Are there side effects of L-glutamine?
L-glutamine is generally well tolerated. In scientific studies, even at high dosages (up to 45 grams per day), few side effects have been reported.
Possible mild complaints:
- Abdominal pain
- Nausea
- Flatulence
These occur in less than 5% of users and usually resolve on their own. Do you have liver or kidney disease? Then it is wise to consult your doctor first.
Natural sources of L-glutamine versus supplements
Your body produces L-glutamine itself and you also obtain it through diet. Protein-rich foods are particularly good sources:
- Beef, chicken, fish
- Eggs and dairy
- Spinach, cabbage, beets
- Nuts and legumes
Research shows that in cases of increased demand, L-glutamine supplements can be an additional source alongside intake through diet.
Good to know
L-glutamine is a versatile amino acid that is abundant in your body and in your diet. It is being researched worldwide in various contexts, such as sports, nutrition, and recovery. Currently, there are no official health claims approved, so remain critical and well-informed. Are you unsure if L-glutamine fits into your lifestyle? Discuss it with a health coach. This way, you will always make a choice that suits you.
Sources
- Santos, T. et al. (2021). Effects of glutamine supplementation on inflammatory bowel disease. PubMed.
- Orthokennis (2020). The effect of glutamine on the gut microbiome. orthokennis.nl
- Bodystore.nl (2025). When should you take L-glutamine?
- Zhou, Y. et al. (2020). Effects of Early Enteral Glutamine Supplementation. PMC.
- Chen, X. et al. (2023). L-Glutamine is better for treatment than prevention in exhaustive exercise. PMC.
- Stichting Ortho Health Foundation (2025). L-Glutamine, sohf.nl
- Cleveland Clinic (2025). Glutamine: Benefits & Side Effects
- IVG-info (2025). Glutamine: an important amino acid for your health
