Glutamine and IBS

Glutamine and IBS

Published on Wednesday, July 27, 2022 by Emily Hamm

Have you heard of GLUTAMINE before?

Glutamine is a non-essential amino acid found in the body that is a great energy source for cells that have a rapid turnover rate (die and regenerate quickly). There has been a lot of research in respect to glutamine and its beneficial effects in the GI tract and it is widely popular in the oncology setting. However, it is gaining more traction in other areas of expertise as it may prove to be helpful with GI disorders.

Glutamine acts in the following ways:

  • Promotes new cell growth
  • Decreases intestinal permeability (leaky gut or weakened junctions between cells in the GI tract, allowing bacteria and pathogens to pass through to the bloodstream and other organs)
  • Suppresses inflammation (has antioxidant properties)

How does glutamine relate to IBS? 

It is possible that people who suffer from diarrhea-predominant IBS may have decreased glutamine synthetase (an enzyme present in the body to help break down glutamine for use by cells) levels leading to intestinal permeability which can lead to more diarrhea. Glutamine may also promote changes to the gut microbiota by changing the environment within the gut which controls the microbiota use and digestion of amino acids.

In a recent randomized, double-blind, placebo-controlled trial, it was found that supplementing with 15 grams of glutamine powder daily for 6 weeks in addition to following a low FODMAPs diet significantly reduced IBS symptoms per the IBS-symptom severity score survey. There were also other significant findings from this study; subjects also reported increased quality of life, better stool consistency and frequency of bowel movements. 

These findings suggest that oral glutamine supplementation may normalize intestinal permeability leading to improved gastrointestinal symptoms in IBS.

This was the first study conducted that assessed the use of glutamine in conjunction with a low FODMAPs diet for the management of IBS. More studies are needed to identify the optimal dosage for glutamine supplementation and long-term effects of glutamine supplementation in IBS patients.

Additionally, as mentioned in this article on post-infectious IBS (PI-IBS), in 2018 the Gut journal published a study comparing glutamine to placebo specifically in PI-IBS sufferers and found that 5 grams of glutamine (2x daily) over an 8 week period reduced IBS symptom severity. 

Should you try taking glutamine to see if it can help your IBS symptoms? 

Talk with a registered dietitian (RD) to find out. Certain people with kidney disease, liver disease or Reye’s syndrome may be at risk when taking glutamine supplements.


Rastgoo S, Ebrahimi-Daryani N, Agah S, et al. Glutamine supplementation enhances the effects of a low fodmap diet in irritable bowel syndrome management. Frontiers in Nutrition. 2021;8. doi:10.3389/fnut.2021.746703 

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