Latest Information About L-Glutamine: Product Reviews, Warnings, Recalls, & Clinical Updates from ConsumerLab.com - ConsumerLab.com (2025)

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Filters Glutamine Side Effects Glutamine for IBS? Glutamine and Exercise What Helps or Worsens Reflux?

Read our review to find the best glutamine (l-glutamine) supplements, avoid pitfalls with labels, and learn whether glutamine helps for boosting the immune system, improving exercise performance, and protecting the stomach from NSAIDS. Plus glutamine dosage, safety and side-effect information. Find out which ones passed our tests and why.

L-Glutamine Supplements Review

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News Release March 13, 2025 Best L-Glutamine Supplements According to ConsumerLab Tests White Plains, NY, March 13, 2025 — L-glutamine (glutamine) supplements are promoted to boost energy and the immune system and for other benefits, but do they really work, and if so, which glutamine products on the market are best?To identify the best products, ConsumerLab recently purchased and ... Product Review Protein Powders, Shakes, and Meal Replacements Review Find Out Which Protein Products Passed or Failed Our Tests

Clinical Update

9/30/2022

Glutamine Side Effects

A CL Member experienced dizziness, nausea, and anxiety after taking L-glutamine. Find out if these are known side effects of L-glutamine, and learn about other potential adverse effects of glutamine in the Concerns and Cautions section of our Muscle & Workout Supplements Review.

Also see our article about supplements that may cause dizziness.

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Clinical Update

9/04/2018

Glutamine for IBS?

Glutamine, an amino acid, plays a role in maintaining the digestive tract. Can taking it as a supplement help people with irritable bowel syndrome (IBS)? Find out what a recent study showed in the Glutamine section of the Muscle Enhancers Review.

Clinical Update

6/19/2021

Glutamine and Exercise

Can glutamine supplementation decrease muscle breakdown from exercise? See what a recent study showed in the What It Does section of our Muscle & Workout Supplements Review. Also see our Top Picks among muscle and workout products.

Clinical Update

1/31/2023

What Helps or Worsens Reflux?

Find out if the following improve, or worsen, symptoms of acid reflux:

Menthol (in toothpastes, mouthwashes and chewing gum)
Alanine
Glutamine
Glycine

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