Glutamine vs Glutathione - What’s The Difference & Which Is Best?
Glutamine and glutathione sound so similar, but they are oh so different! So in this short article, I’m going to show you how they differ in terms of what they're made of, how they help your health, and we'll even look at where they are both found in the body, in foods and in supplements. And it might get a little sciencey at times - but don't worry, because I'll explain it all in plain English. And hey...I might even have an Ironman analogy for you, that will help it all make sense. Let's go!

Table of Contents
Video: For the simplest explanation of how these 2 amazing ingredients work, check out our video above!
1) What are glutamine and glutathione?
Well, glutamine is an amino acid. While glutathione is actually an antioxidant. We’ll look at why this distinction is important in a minute when we look at the benefits of them both.
But first a quick fun fact: did you know glutamine and glutathione share a similar origin story? You see, Glutamine is a single amino acid, while Glutathione is actually made up of 3 amino acids?
Ok…this may not be a “FUN” fact per se. But you know, we found this interesting. So moving on!
2) How important are they for our health?
So glutamine is actually the most abundant amino acid naturally found in our bodies. While glutathione is arguably the body’s most important antioxidant. And is often referred to as its master antioxidant. Meaning they are both extremely important for our bodies, almost like joint gold medal winners!
What are the main benefits of glutamine & glutathione?
When it comes to the PRIMARY benefit of them things start to get different.
So for Glutamine its main benefit is that it fuels the cells lining our intestinal wall and supports the integrity of the gut barrier. Meaning it helps fight leaky gut, helps with bloating and supports the digestive system. In fact, here’s a quick extract from a previous article we wrote explaining how glutamine helps with leaky gut.
This 2011 meta analysis of 86 different studies on glutamine and gut permeability, found: “A significant body of evidence indicates that glutamine preserves the gut barrier function." And just as importantly the researchers found “Glutamine is considered the most important nutrient for healing of ‘leaky gut syndrome’ because it is the preferred fuel for enterocytes and colonocytes”
By contrast, Glutathione’s main function is to kill free radicals and inflammatory compounds called Reactive Oxygen Species. Meaning it helps fight inflammation, aging & toxins, while also supporting our energy levels.
And I know this reads like geek speak and may have you feeling like you ARE back in senior year chem class, so let me explain it with an Iron Man analogy.
Iron Man analogy
Photo: Glutamine is like the ARC reactor of Ironman, while glutathione is more like the weapons he fights with.
So you know how Iron Man is powered by his ARC reactor, the glowing circle on his chest. This is his energy source and it gives him the strength to fly around and do all kinds of crazy things. Well, that is kinda like Glutamine.
Now you know how Iron Man fights bad guys and kills them using his arsenal of fangle dangle weapons? Well, that is kinda like Glutathione.
In other words, glutamine is like a fuel for our body and glutathione is like a fighter for it.
Anyways, enough Iron Man chatter, after all here at Essential Stacks we are all about researching the best ways to improve your gut health. So the next big question is...
Which is better for gut health - glutamine or glutathione?
Well, for glutamine it is clearly helpful for gut health. In fact, it is the number one reason people are so interested in this little amino acid these days. And as we just looked at, it helps with the integrity of the intestinal lining and thus fights leaky gut.
But what about glutathione?
Well, it turns out that glutathione indirectly helps gut health by reducing intestinal inflammation, fighting oxidative damage and supporting healthy detoxification pathways.
Some animal research have even suggested that glutathione may strengthen the gut barrier by reducing intestinal cell death. In other words, they both help gut health…but of course, glutamine helps more and does so in a more direct way.
3) Sources of glutamine and glutathione
a) Glutamine & glutathione in the body
While both are naturally produced and found in the body - interestingly, both can be depleted due to things like stress, injury, aging and poor lifestyle, among other reasons. And in these situations, it may be helpful to go full Indiana Jones and seek external treasures…I mean sources of glutamine and glutathione. Which brings us to the next question...
b) Glutamine & glutathione foods
Meaning can we get more through our diet?
For glutamine the answer is yes and you’ll find it in most protein-rich foods, like meat, seafood and eggs. And if you want to see a complete list of foods high in glutamine, check out our best glutamine foods article. This will show you the highest glutamine foods you can eat, including how much glutamine you’ll get per serve.
Photo: glutamine rich foods would include pretty much any that are high in protein, eg meat, seafood, eggs etc.
Now for glutathione, you will also find this in some foods, especially antioxidant rich foods like avocados and spinach. But here’s the thing…once ingested glutathione breaks down rapidly. Which means inside your gut it breaks apart into the 3 amino acids it is made of. This means that it can be hard to increase glutathione levels in your body by eating glutathione-rich foods.
And this has led researchers to conclude that “dietary glutathione is NOT a major determinant of circulating glutathione”.
With that said, you can potentially eat foods rich in compounds that can encourage glutathione production. We call them precursor foods. And a great example would be sulfur rich foods like meat and cruciferous vegetables.
c) Glutamine & glutathione supplements
Well, glutamine is easy to find in supplement form. And you’ll usually find it in capsule or powder form (for example, this is the pure L-Glutamine powder we make).
If your main goal for taking glutamine is to support your gut health, then powder form is best.
And that’s because most experts agree 5-10 grams of glutamine per day is best for leaky gut and bloating. In other words, l-glutamine powder is much easier to take compared to swallowing 10 capsules.
And if you want to learn why experts believe 5-10 grams is ideal, check out our article on L-glutamine dosage.
Photo: If you want to try the L-Glutamine powder pictured above, you can buy it on Amazon or direct from us
As for glutathione, you can find this in supplement form as well. Usually it comes in capsule or liposomal form. But like with glutathione-rich foods, there are serious doubts about whether supplemental glutathione can actually make its way into the cells intact.
And if we go back to the previous study we looked at, we can see researchers found “it is NOT possible to increase circulating glutathione to a clinically beneficial extent by the oral administration of glutathione.”
As such, from what we’ve seen from all the research - as of today glutathione supplements may not be worth buying.
4) Our conclusion
So now you know the differences between glutamine and glutathione and hopefully you can see just how important they both are for our health.
While glutamine is mainly about gut health, glutathione is more to do with inflammation, aging and energy. And as you saw, we make both of them naturally in our body, and you can also find them in foods and supplements…but of course…these external sources of glutamine and glutathione differ in terms of how helpful they may be.
And now we want to hear from you…
- Have you tried glutamine or glutathione?
- And what benefits did you find taking them?
Let everyone know by leaving a comment below.
Photo: If you want to try the L-Glutamine, you can buy it on Amazon or direct from us.
5) Comparison table of Glutamine vs Glutathione
Glutamine |
Glutathione |
|
What it is |
Amino acid
|
Antioxidant Made up of 3 amino acids
|
How important it is |
Most abundant amino acid in body |
Body’s most important antioxidant |
Primary benefit |
Fuels & supports integrity of intestinal lining → fights leaky gut & supports digestive system |
Kills free radicals & inflammatory compounds → fights inflammation, aging, toxins etc & supports energy |
Helps gut health |
Directly - per above |
Indirectly via inflammation & detoxification |
Found in body |
Produced naturally in body, but can deplete with stress, injury, aging, poor lifestyle etc |
Same |
Found in foods |
Protein-rich foods like meat, seafood, eggs etc |
Antioxidant-rich foods like avocados, spinach etc NB: cooking & digestive system break down glutathione |
Found in supplements |
L-Glutamine
|
L-Glutathione
|
Evidence Based
An evidence hierarchy is followed to ensure conclusions are formed off of the most up-to-date and well-designed studies available. We aim to reference studies conducted within the past five years when possible.
- Systematic review or meta-analysis of randomized controlled trials
- Randomized controlled trials
- Controlled trials without randomization
- Case-control (retrospective) and cohort (prospective) studies
- A systematic review of descriptive, qualitative, or mixed-method studies
- A single descriptive, qualitative, or mixed-method study
- Studies without controls, case reports, and case series
- Animal research
- In vitro research
References
- Richie JP Jr, Nichenametla S, Neidig W, Calcagnotto A, Haley JS, Schell TD, Muscat JE. Randomized controlled trial of oral glutathione supplementation on body stores of glutathione. Eur J Nutr. 2015 Mar;54(2):251-63. doi: 10.1007/s00394-014-0706-z. Epub 2014 May 5. PMID: 24791752.
- Rao R, Samak G. Role of Glutamine in Protection of Intestinal Epithelial Tight Junctions. J Epithel Biol Pharmacol. 2012 Jan;5(Suppl 1-M7):47-54. doi: 10.2174/1875044301205010047. PMID: 25810794; PMCID: PMC4369670.
- Labow BI, Souba WW. Glutamine. World J Surg. 2000 Dec;24(12):1503-13. doi: 10.1007/s002680010269. PMID: 11193715.
- Lenders CM, Liu S, Wilmore DW, Sampson L, Dougherty LW, Spiegelman D, Willett WC. Evaluation of a novel food composition database that includes glutamine and other amino acids derived from gene sequencing data. Eur J Clin Nutr. 2009 Dec;63(12):1433-9. doi: 10.1038/ejcn.2009.110. Epub 2009 Sep 16. PMID: 19756030; PMCID: PMC3249386.
- Lacey JM, Wilmore DW. Is glutamine a conditionally essential amino acid? Nutr Rev. 1990 Aug;48(8):297-309. doi: 10.1111/j.1753-4887.1990.tb02967.x. PMID: 2080048.