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Why is glutamine not recommended by some practitioners? Glutamine, often prescribed by doctors to help heal leaky gut, may not be as safe as many believe. What are the long term side effects of taking L-glutamine?
What is L-glutamine
Many articles recommend using glutamine (also labeled L-glutamine) as a supplement to help heal leaky gut. Glutamine provides energy to the small intestine and when converted to glutamate can accelerate healing.
Tangentially, glutamine is also recommended by some to abate sugar cravings, or among body builders and athletes for performance and recovery.
Certainly many doctors prescribe glutamine for their patients with leaky gut.
Glutamine concentrations decrease during periods of disease or stress, thus one motivation for supplementation.
And the body’s ability to expel glutamine means that many doctors see glutamine as benign, with no side effects even at high doses.
Its depletion causes compromises in gut function … so why not supplement?
Short term benefits
One of the biggest problems with conventional “leaky gut” protocols is their heavy reliance on glutamine. For years, people have been told to take 10, 20 or even more grams of glutamine daily to repair the gut lining.
Yet many people report little lasting benefit, and it’s difficult to find examples of someone who permanently resolved gut issues simply by taking glutamine. At best, glutamine often appears to function as a temporary band-aid rather than a true solution.
Glutamine becomes glutamate
The reason may be that much of glutamine’s value comes from what it eventually becomes: glutamate. Glutamate is a primary fuel source for the cells that line the intestinal tract.
In fact, the vast majority of dietary glutamate is consumed directly by the gut cells before it ever reaches the rest of the body. These are the very cells responsible for maintaining healthy tight junctions and forming the protective barrier that people hope to restore when addressing “leaky gut.”
Instead of indirectly supplying these cells through glutamine, glutamate provides them with the fuel they use immediately.
Glutamine = glutamate + ammonia
The key distinction is that glutamine is essentially glutamate with an ammonia group attached. When the body converts glutamine into glutamate, it must remove that ammonia. As a result, glutamine supplementation can increase the body’s ammonia burden.
Glutamate, on the other hand, can bind ammonia to form glutamine, potentially reducing the amount of free ammonia circulating in the body. From this perspective, glutamine doesn’t simply provide glutamate — it also introduces additional ammonia that the body must process and eliminate.
Glutamine’s ammonia load
This may help explain why high-dose glutamine protocols often lose effectiveness over time. Initially, some individuals may experience benefits because glutamine is being converted into glutamate.
However, as supplementation continues, the increasing ammonia load may become a limiting factor. Some people even report symptoms such as agitation, overstimulation or insomnia when taking glutamine, suggesting that not everyone tolerates large amounts well.
Glutamine fuels …
There are additional reasons to question the widespread practice of supplementing glutamine in gram quantities. Glutamine is not only a fuel source for human cells; it can also serve as a nutrient source for rapidly growing cells and microorganisms.
Research has shown that many cancer cells are highly dependent on glutamine metabolism for growth and survival. In fact, glutamine is so important to certain tumors that researchers often describe them as “glutamine addicted.” This does not mean glutamine causes cancer on its own, but it does raise questions about whether indiscriminately increasing glutamine intake is dangerous.
Similarly, microorganisms can utilize glutamine and related compounds as nutrients.
Studies have demonstrated that various bacteria can use amino acids, including glutamine, to support growth and metabolic activity. This raises the possibility that excessive glutamine supplementation harms the host by providing resources to unwanted microbes.
Glutamine’s higher mortality rates
Perhaps most surprising is that glutamine supplementation has not consistently produced positive outcomes in clinical trials.
In a large study of critically ill patients, those receiving intensive glutamine supplementation experienced higher mortality rates than patients who did not receive glutamine.
While these findings occurred in a hospital setting and cannot automatically be applied to healthy individuals, they demonstrate that glutamine is not the universally harmless nutrient it is often portrayed to be.
The body prioritizes glutamate
The body’s physiology also suggests that glutamate itself is highly valued.
Glutamate is the most abundant neurotransmitter in the nervous system and one of the most important amino acids in cellular metabolism. The body has numerous pathways to manufacture glutamate from other amino acids, including glutamine, histidine, proline, arginine, asparagine and several others.
Multiple liver enzymes are dedicated to producing glutamate, indicating that the body prioritizes maintaining adequate glutamate availability.
Glutamate in breast milk
Another interesting clue comes from human milk. Among the free amino acids present in breast milk, glutamate is by far the most abundant, accounting for more than half of the total free amino acid content during lactation.
This suggests that glutamate plays an especially important role during periods of rapid growth and development.
Glutamate high doses safe
Research also indicates that dietary glutamate is extensively metabolized within the digestive tract and does not significantly raise brain glutamate levels under normal dietary conditions. Human studies have found dietary glutamate to be safe even at very high intakes, largely because the gut uses so much of it before it can enter systemic circulation.
Glutamate more logical
Taken together, these observations suggest that many of the benefits traditionally attributed to glutamine may actually stem from its conversion into glutamate.
If the goal is to support gut cells directly, glutamate is the more logical choice because it provides immediate fuel for the intestinal lining while avoiding the additional ammonia burden that accompanies large doses of glutamine.
This perspective may help explain why glutamine supplementation often produces inconsistent results, while direct glutamate intake appears more aligned with the body’s natural physiology.
The body maintains its own glutamine
Finally, glutamine is considered a “conditionally essential” amino acid precisely because the body can manufacture large amounts of it on its own. That makes the common recommendation to consume 10 to 30 grams per day supplemental glutamine seem less intuitive, especially when the body already maintains some of the highest circulating levels of glutamine and glutamate of any amino acids.
Side benefits to glutamate supplementation
Glutamate’s benefits don’t stop with the gut.
Adequate levels of glutamate are required for healthy cellular function throughout the body. Research also shows that glutamate can help protect against GI injury associated with H. pylori. Interestingly, H. pylori survives by producing ammonia and literally requires nickel to live, which is one reason I believe nickel toxicity is often at the root of chronic gut issues.
Beyond gut health, glutamate is known for helping reduce sugar and alcohol cravings, improve energy, support wound healing and promote healthy brain function. Pure MSG is simply glutamic acid (glutamate), and many people are surprised to learn that this misunderstood nutrient may offer benefits that extend far beyond digestion.
Other ways to resolve leaky gut
- Read about the Vitamin A Detox Diet that is also low copper. (This is a new and revolutionary detox diet that I’ve used myself to reach my health goals.) Includes free food lists and printable grocery list.
- Learn more about the Low Nickel Diet.
- Consider removing lectins from your diet. Here’s a Low Histamine and Lectin-free Combined Food List with printable if you’re sensitive to both histamines and lectins.
- Reduce histamines and oxalates, article with printable here. Or, just the Low Oxalate Food List here.
- Discover your food intolerances here.
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Note: This article was fully rewritten and updated in June 2026. Some comments below may no longer be relevant, as they were written in response to the original version of the article. I also removed a few comments that were completely unrelated to the updated information.
Renee Kohley says
No WAY. Thank you for this information – I had not heard of this side of the story and have definitely been prescribed LGlutamine to take in the past. I appreciate this! Thank you!
Megan Stevens says
You’re welcome, Renee. Thank you for commenting. 🙂
Kristine says
Hi- I have read all the comments below and find them all fascinating. Here’s the thing- it just depends on the person. I used to be able to take L-Glutamine in supplement form and it helped me tremendously. I would heal from it. But after 3-5 years of a stress-diet high in sugar and antibiotics for illnesses, I developed a BBB and major leaky gut issue. Now I can’t tolerate L-Glutamine at all. I’ve gone back over this past year and retried it several times. My intolerance got so bad I couldn’t even drink bone broth- I’ve learned ‘everything in moderation ‘ even when you are healing your gut. I can’t tolerate VP collagen/gelatin at all- it made my extremely sick and killed my gut. I agree with L-Glutamine potentially feeding pathogenic bacteria, as well as in relation to increasing heavy metals. Especially if you can’t digest it due to the new mucous layer protecting your damaged small intestine lining and it ferments in your gut. This also applies to things like DGL and other mucilaginous herbs- which I also cannot tolerate now. A whole foods diet doesn’t work when you have major food malabsorption problems either… in the end, you just need to figure out what works for you as an individual and go with that- what I have learned, is to always listen to my gut! What I also know- blame the true ‘bad guys’- antibiotics and refined sugar that our healthcare and capitalistic society keeps shoving down our throats.
Amy says
Yes yes and yes!
Emily @ Recipes to Nourish says
I had no idea about this! Thank you for sharing. I have never taken it, but I’m glad to know about this now. I’ll stick with gelatin 🙂
Megan Stevens says
Thanks for sharing your thoughts, Emily.
Herman Rutner says
Make sure the gelatin is from grass fed cows, not BSE or mad cow disease bearing cows fed cattle cadavers and bones. Beef Collagen may be safer choice.
linda spiker says
Always an education. I have known many people who have treated leaky gut with glutamine. Good to know.
Megan Stevens says
I hope more research will continue to clarify the complexity and dangers of this supplement.
Ed says
I’ve taken L- Glutamine powder without having any issues ..Besides I do feel it’s helping me with my stomach issues along side taking aloe vera juice as well….So it might not work for others but I feel it works for me and I’m staying with it..
Lisa says
Same here. I learned about l glutamine from a doctor a number of years ago. He told me about all the studies on it showing it to be very effective in helping stomach and gut issues. I remember the first time I took it. Within around 30 minutes the inflammatory pain in my gut was much better.
I don’t take it continuously. I’ve never had anything but good effects from it. If it was converting to glutamate to the point of being problematic that would be evident in mood and neurological symptoms. I feel calmer and better from glutamine.
I like Paul Jaminet a lot but he is a little on the paranoid side about supplements. The truth is that they are by and large very safe and low toxicity. The adverse events data indicate that there is like 1 death per decade or some ridiculously low number like that attributed to vitamin, mineral, herbal, amino acid supplementation. And that is ATTRIBUTED not a proven cause of death in that 1 person typically.
Food is great but sometimes it alone just doesn’t cut it for the fastest symptom relief and healing. I’m reminded of Sally Fallon and her claim that people with pellagra healed on a diet with unpolished brown rice but not with supplemental b vitamins. I was skeptical so I researched it. In outbreaks of pellagra people recovered much faster with b vitamin supplementation than with food alone.
The reason these folks get duped is because they fall into the evolutionary notion that nature is perfect and food is natural so it contains everything needed in the proper balance with all synergistic constituents. No it isn’t and no it doesn’t. Especially in industrial countries. Even if you eat the best you can get in terms of organic or pastured. And the truth is it never did. Nature is screwed up. That’s the reason we die and it’s the reason ancient people had higher mortality that moderns.
Ken says
Totally agree, has healed my ulceration from colitis as the anti inflammatory pills weren’t clearing that up. After 3 weeks of concentrated powder doses of l-glutamine tests showed an all clean intestine. Doctor still won’t believe it. And this article to me is someone picking a topic to sell themselves and ultimately sell product. I apologize in advance but I don’t trust contrary posts like this.
Megan says
Hi Ken, happy for you, and thanks for sharing your experience with glutamine. Actually, I think it’s really important to present both sides of supplements so all of us understand the dangers for some people. It sheds light on others’ experience with this supplement, so they understand why they reacted, even if it wasn’t your experience.
Cheryl says
I appreciate this article so much!
I’ve been on a gut healing journey and have tried glutamine twice both times I get severely agitated, angry and frustrated. I was shaky and very hyper. (I did love the energy I got tho!) I also ended up with severe insomnia for two nights after taking it. This was only 5 g of micronized L-Glutamine in water.
Unfortunately this product is not for me. I truly wish it was as I bought a big container of the stuff!
It’s definitely not a one size fits all with glutamine.
I will try alternatives.
Thank you !!
Megan says
Thanks for sharing, Cheryl, and I’m so glad it was helpful. 🙂
Melissa says
I’m sorry you mention in your post that tests revealed a all clean intestines? Could you please elaborate on the tests, what type of tests you had run to establish a clean intestine? Are you referring to some type of functional medicine blood test or endoscopy perhaps? Thank you for your help. I’m extremely interested in this subject as thus far the doctors have not established a protocols in testing in regards to intestinal health besides maybe a endoscopy and certain other markers on blood tests that are not typically used within “normal medicine.”
Robin Jones says
Agree!!! This articulate does seem paranoid. I like the added knowledge but also in my case I’ve had a NUTREVAL test (organic acid test) and both my glutamine and glutaric acid are low.
I’m sticking with glutamine
Jessica from SimplyHealthyHome says
Good post. I didn’t know this. I will be sharing as I see this recommended so often.
Megan Stevens says
Thanks, Jessica.
Sandrine Love says
I tend to trust whole foods over supplements in most cases!
Megan Stevens says
Thanks for sharing, Sandrine.
Andrea Wyckoff says
So interesting! You brought up a lot of good points. Years ago I was told to take Glutamine, but I never took it for very long, especially since I have just never been much of a supplement taker, preferring whole food sources for nutrients and vitamins. Mother Nature knows best! Thanks for the great info!!
Megan Stevens says
Thank you, Andrea!
Zen Jen says
There are a lot of enthusiastic reviews of Knox gelatin at Amazon. Seemingly it oonfers the same benefits as the more high-end products. Sometimes I wonder how much difference there really is between all the various brands.
Nick says
And what are the benefits in regards to animal cruelty?
Angela says
From personal experience I used L-Glutamine to heal my 7 yr olds leaky gut. So I know this absolutely not to be true.
Niya Ray says
Angela, when I go to test for food sensitivities using electro-dermal biofeedback technology, it always shows extreme sensitivity to Gluten, some other grains, L-Glutamine, gelatin, most protein (except some fish), most fats and anything with Dairy, some veggies and many fruits also. And I do have IBS, a leaky gut, hypothyroidism and anxiety also. So this article is ABSOLUTELY TRUE!!
Noelle says
I was wondering if the great lakes collagen is good to use?
Anya | Prepare & Nourish says
This is such an eye-opening article for me. I have been prescribed by an integrative doctor to take this supplement but always wondered why if I can take a whole-food collagen/gelatin instead. I did consume L-glutamine sporadically but not consistently and not in dosages my doctor wanted me to take. I think I knew intuitively that it was not the best for my gut or my health.
Megan Stevens says
I love that intuition plays a role in our healing. Thanks for sharing.
Small Footprint Family says
I am on a leaky gut protocol that prescribes supplemental l-glutamine, but you know, my gut instinct (haha) keeps telling me not to take it. Now I know why. I bought a case of Great Lakes collagen hydrolysate instead, and add it to my morning coffee and evening water. I’m not certain if it’s helping my gut, but my nails are growing so fast!
Lisa Truitt says
I have to respectfully disagree. I have achieved healing of my gut to a far greater degree using glutamine supplementation than with just WAPF whole food principles. I have spent a lot of time over the years doing the bone broths and gelatin etc, the whole program and never healed to the level that adding a glutamine healing regimen has done.
Here is my theory on that: there is simply such a constant barrage of insults in the form of naturally occurring food toxins and chemicals from pesticides and antibiotics and numerous other chemicals from manufacturing and modern technology combined with poor food quality even if a person gets the best food available and compromised digestive functioning so that not as much of what is in food is digested and absorbed that many people especially with health problems can’t get enough of this and other amino acids to support the fueling and repair of their intestinal lining as well as for other functions. Even doing every Wapf thing that is possible to do. Especially people who have serious health issues.
As far as these “stories” of harm whether they be theoretical in studies or anecdotal I am definitely going to be following up to see if this is true. I highly doubt it. And it won’t be the first time that I’ve caught Weston price purists in untruths. For example Sally Fallon’s claim that manufactured so called synthetic b vitamin supplements don’t cure b vitamin deficiency diseases such as beri beri and pellagra that only whole food sourced vitamins do. I researched that and every single medical record I could find of the treatment of beri beri and pellagra outbreaks in various parts of the world indicates that it was found that people were cured much more quickly with b vitamin supplementation than with food sources of b vitamins alone. And it was plain old cheap lab manufactured b vitamins that were used.
The Weston Price people have this romantic idea that nature is perfect and if we can just all live naturally enough no man made interventions are necessary and not only are the not necessary they are harmful. I believe this is a false paradigm. I think the reason they fall for this false paradigm is because they have an atheistic evelotionart worldview. I don’t hold this or believe it’s correct but instead hold to a worldview that the world was created with the level of perfect that the WAPFers think exists in nature but that that got ruined and we are in a process of break down and are devolving not evolving in the sense of gaining greater order and perfection. Thus as a result the proper man made interventions can do a lot to counter act and make up for this.
I have experienced nothing but healing and benefit from periods of glutamine use and I’ve read and heard the same stories from many many other people and rarely heard a negative story and never one of any kind of serious harm. Just that it didn’t work for them and it’s likely that in these cases the person simply wasn’t taking enough. I’ve heard one or two stories of nausea or some like thing but these can be herx symptoms which I experienced a bit as well but they are temporary. Some people just don’t know this and immediately give up thinking its harming them.
As far as glutathione goes deficiency as a far bigger problem for the vast majority particularly for ill people who also often have detoxification defects. More glutathione means better detox and is why substances that improve glutathione levels improve energy and stamina and overall health in people who are ill and chronically fatigued.
As far as studies on nutrients it’s important to understand there are a lot of methodologically flawed studies out there that are done to purposely make nutritional interventions look useless or even harmful. There is a lot of incentive by various entities to make nutrition and alternative health care options look bad because they are competition to the mainstream. It is important to look at the source of the studies.
With studies that show the benefits of nutritional supplementation many well conducted studies are done by independent researchers and while research being fudged by supplement makers is not non existent there is a lot less of it than the negative studies many of which are done by entities that have serious conflicts of interest and have loads of money to conduct these expensive studies and stand to gains billions by flawed studies that discredit the competition.
This just isn’t the case with the positive studios most of the time. Especially when your talking about some totally unpatentable substance that no one can make massive money off of or make enough money from to afford to have expensive double blinded studies conducted.
Mainstream research is full of positive studies on glutamine. I just read info from the blog of a holistic gastroenterologist Gerard Mullin that the consensus of meta analysis of peer reviewed research is showing that glutamine heals leaky gut and shifts the microbiome from an obesogenic dysbiotic one to a normal lean person microbiome. I think that is pretty exciting!
If you go look at reviews say on Amazon for instance of various brands of glutamine you will see almost nothing but rave reviews. It is a tiny number that have any negative comment and those are minor. Many say this stuff is a one item tool kit and helped my health in so many ways. It healed me of ibs or ulcerative colitis.
Also this generally only takes a short course of high dose glutamine and then either a small maintence dose or many discontinue it. Some just occasionally do a round of it. Maybe once every few months.
Andrew Saul of doctoryourself.com asks the question: if supplements are so dangerous where is the evidence? Where are the reports and the bodies? If you look at the data the government keeps on adverse events reporting deaths by supplements are like 1 or 2 per decade and minor adverse events of ill health effects of some kind are higher but very low in the tens up to hundreds out of millions of people.
I think you are taking the knee jerk “this is not a whole food” so it must be bad WAPF position and that this is flawed and does an injustice to the people you are influencing that might have their health revolutionized by taking advantage of it.
Ryan Michael Ballow says
What’s interesting is that you took all of that time to propose mostly theory, based on things you’ve read, where obviously you’re discounting all of other other quirky factors that pretty routinely underlie normal human physiology.
You “disagree” with the notion Glutamine might not be beneficial for particular people, which is asinine, because you are not those particular people. You are you, and you benefited from Glutamine supplementation. Perhaps you didn’t have a particularly nefarious pathogenic bacteria infection in your gut.
I did. And Glutamine, quantifiably, irrefutably made things CONSIDERABLY WORSE. Right away. Without question. I tested it thoroughly, several times. — The author is 100% right as it relates to Glutamine facilitating pathogenic bacteria in the gut that might be overgrown, and manifest in reflux, bloating, or other symptoms similar to SIBO.
TLDR: You are interpreting the advice as it relates to you, and making an overall, overarching determination of the advice. — This is a logical fallacy.
You don’t have to go further to disprove your notion that Glutamine is universally beneficial than me (and many many many many many other similar examples you’ll have to hunt for around the web, that do exist), someone with a bacterial overgrowth, that Glutamine directly negatively affects.
TLDRX2: You’re being short sighted, and thinking everyone’s gut is similar to yours. — I couldn’t even believe I was reading what you wrote. You’re one of those people that truly believes you know what you’re talking about, and that it’s universally applicable. — You folks are literally the worst ;).
Calogero Fiore says
You are so right!!!
ive suffered with leaky gut (Sneeze my brains out if I eat any gluten and have phlegm from hell if I eat any dairy) Ive, through trial and error doing high fat low carb, low fat high carb, keto, paleo, meditarranean an found finally GAPs, SCD that Bone Broths instead of healing gives me a terrible symptoms not sureif its the autoimmune disease called Relapsing Polychondritis where my LEFT EAR burns like hell and goes totally RED fpr HOURS or the rest of the day, I stopped and after a while took the advise of a ‘nutrionist’ at wholefoods nd purchased Collagen and L-Glutamine, EVERY time I take Collagen BANG!! my ear goes red, so I stopped after a bout a week I thought let me try Glutamine powder, BANG!! My ear throbs and is red again, this stuff is the same or probably made from ground up bones and animal tissue, I have no problem with eggs, chicken in small amounts but those three Bone broth/L-Glutamine/Collagen powder gives me serious gut reactions, I believe the red ear is an autoimmune reaction in my gut to this crap forgive me words but for me this stuff has hurt me and only did this cause i always hear, leaky gut? The eat/drink bone broths, take Glutamine powder, for me it didnt work, infact it hurt me.
I didnt understand or know of any bacterial connection, but I did know from experience something is happening and my gut is going nuts when I take those powders, now I will give them away, you can get glutamine from cabbage anyway, in my opinion its not the glutamine but the source of that glutamine that gave me problems, i.e. probably some animal bones or carcasses
Sam Wise says
All the above people are or were experiencing increased mercury/lead (and other metals) elimination symptoms resulting from inadvertent heavy metal chelation, this was produced by increased Glutathione levels resulting from supplemental Glutamine.
Solution is to keep taking, but at much lower dose, and with addition of Glycine. Use ratio of 2:1 Glutamine to Glycine. Start at low dose, e.g. 300mg Glutamine with 150mg of Glycine, lower if you can find it. Split pills if you can. You won’t need Cysteine, your body will make it and/or you’re already getting plenty eating healthy food OR junk food. When combined these are the ingredients needed to produce glutathione inside our cells. Why not just take glutathione? Because it won’t go into cells like it can when made inside cells with cysteine, glycine, and glutamine. Also, glutathione in pill form doesn’t survive digestion assimilation well enough to have much impact. Instead it does opposite, a higher thiol content leading to heavy metals being mobilized resulting in symptoms and complaints described by those comments above.
Always start closer to zero for all supplements, both for vitamins, and medicines not prescribed, then work up slowly each day until discomfort or symptoms arise, then back down to previous level, maintain for some period, your choice, then try increasing again till symptoms trouble you again, reduce, repeat.
Detoxification of metals should be done slowly, with breaks for recovery and elimination. Typical schedule is 3 days of treatment, followed by 4 days recovery, elimination, and focused supplementation with healthy minerals which were also removed or lost in detoxification process. Repeat for 1-5 years, depending on your load, and continued toxins exposure.
Calogero Fiore says
For some reason Glutamine and Collagen and bone broth gives me red burning ear (left) for hrs and the only disease I found was relapsing polychondritis which is affected by ones diet, one lady said she recovered from this nasty disease by avoiding meat and going on the Mcdougal diet of starches like potato etc diet, not only would I get burning left ear but night sweats, one guy who is a paleo nutritionist laughed and said those are just meat sweats, i said I dont care I dont want to get them and today started a low fat starch diet, I believe it can work and isnt as dangerous as many seem to think, in my case with fatty liver and gallbladder polyps I have to be careful as with no fat the GB will work less and may become even more sluggish than it is, but having a leaky gut or damaged gut then CKK enzyme system which tells the GB to release once fat hits the gut isnt going to be working cause this system is interfered with cause of the damage, also one guy who was overweight went on a potato ONLY fast or diet for months and high bloods were better than when he started, the problem is the fuel that we choose, by combining the two FAT+CARB as in cake,biscuits, chocolate, cheesecake, lasagna etc etc … all the tasty food that we find hard to resist, our biology makes them hard to resist cause we are constantly expecting famine and so the system wants you to pile away in the storehouses (adipose, Liver, Vicera) we are geared to store fat whether it comes from fat or carb, the only problem in my case is that protein+fat route is more hazardous for the problems I have.
Sugarboo says
I’ll write more as soon as I can Calogero Fiore
Calogero Fiore says
I’ll keep a look out on my email, Im happy I found one person in the world that has the same ear problem maybe not the red burning ear but very close, it seems to me that the part in the gut that corresponds to the ear is being affected? Inflamed? In case we lose contact here is my email Calogerofiore(at)yahoo.com , wish you well till next time.
Sugarboo says
I believe it’s the gelatin or bone broth because maybe they are from non- organic and non grass fed becomes and pigs.,the animals have high inflammation from eating the grains and then we eat it and it throws our own omega 3-6-9’s off and causes high inflammation for us, and then we get intense pain from the inflammation. At least that is what I think is happening.
Sara Hana Sternberg says
Hi Sam, I’m appreciating your input here. So you are saying, that for people who may react negatively to L-Glutamine, to keep taking it with in smaller doses with addition of Glycine? I was just reading that L-Glutamine can increase the ammonia levels and for this reason Trans Alyanyl Glutamine is a better and more absorbable option. What do you think of this? I know ammonia is a real issue for me. I tried some L-Glutamine this morning and found it very painful for my gut. About 2.5 grams worth. I may also have excess Glutamates. I have tested high for lead. Where does all of this fit into you perspective (the variations of Glutamine and the ammonia issues)?
Light Worker says
I’m interested in knowing if maybe the people who experienced a proliferation in pathogenic bacteria had an unbalanced bacterial population prior to glutamine supplementation. If that is the case I think it would be sensible to just add a disclaimer that an important precondition to taking glutamine is supplementing with a broad spectrum, high strength probiotic for 2 months to correct the imbalance.
Hip777 says
Quoting Ryan: “You are interpreting the advice as it relates to you, and making an overall, overarching determination of the advice. — This is a logical fallacy.”
But that is exactly what the original article is also doing, with its headline “GLUTAMINE: NOT Recommended for Leaky Gut”. It may be that some people don’t tolerant glutamine, but many others do, so for the article to make an overall, overarching conclusion of “GLUTAMINE: NOT Recommended” is not correct.
Roy Edwards says
You are confusing MSG with Glutamine and therefore you are a liar and a fraud. You are confusing people by spreading lies. Glutamate and Glutamine are NOT the same fucking thing. You fucking loser moron.
Cheryl H. says
I used L-Glutamine for leaky gut and had a HORRIBLE reaction!! I agree that it affects the brain negatively as I had disturbances in my vision and could actually feel my brain “mis-firing” for lack of a better description. I felt “drugged” when supplementing with this. I have even reacted to the Glutamine in a vegetable protein powder I purchased. Will never use that supplement again!
My leaky gut is severe and have food intolerances as a result.
Elliott Kaye says
I had a horrible reaction to glutamine as well. Side effects included increased fatigue, muscle spasms, heart palpitations and increase anxiety. Definitely didn’t agree with my body and I have begun to have reactions to some foods.
Robin says
I think the main reason L-glutamine doesn’t work for everyone is probably because some people with leaky gut also have a leaky BBB (blood brain barrier). I am one of those unlucky people it seems. L-glutamine gives me migraines (as do any excitatory amino acids and foods/supplements that are stimulatory). Here are a few links that discuss “leaky brain”:
http://www.drperlmutter.com/leaky-brain/
https://www.sciencedaily.com/releases/2014/06/140602104749.htm
http://www.ei-resource.org/easyblog/entry/treatments-to-protect-and-heal-the-blood-brain-barrier/
Anwar says
Hi i am also in leaky gut protocol last 3 years.l cannot take l glutamine even 500mg, i feel horrible headaches and chest spasms. Now i am using colostrum and digestive enzymes and i feel much better
MassiveQuantitiesofPie says
Glutamine easily crosses the BBB in everyone. It can cause serious anxiety, panic, headaches, and heart palpitations, among other symptoms. It doesn’t happen for everyone obviously, but if you’re prone to anxiety, panic, headaches, or heart palps, it can.
Anna Burns says
I have leaky gut and systemic candida, or at least I did. I have been on high dose probiotics, digestive enzymes, as well as 20 mg per day of glutamine. I have not had any trouble with the glutamine. I have no idea if it is healing my gut or not, but have been religiously taking it. I just tried Vital Proteins collagen peptides last night for the first time and had an adverse reaction to it. It gave me a headache and it really bothered my stomach. I did not take a full dose. So, I don’t know what to think. I don’t understand why I had such a bad reaction to the collagen peptides. I know in my case, my ‘gut’ has been resistant to the collagen for a long, but my health care professional convinced me to try it. Everyone is so different. I’m open to input. I just want to heal my body, in the fastest way without conventional medicine if possible.
c.difficile says
Hi Megan, for Hashimoto’s people who have low antibodies (paleo autoimmune is working) but zonuline elevated and head symptoms (migraines etc. not hystamine caused) what do you think about OKG or OKG+glutamine for leaky gut? I guess glutamine only could give some sides (probably microglia issues) but OKG stimulates immune system too.
BTW low calproctine and no indican/scatol disbyosis suggest to approach directly leaky gut, isn’t it?
m cook says
Glutamine worked great for me for a few months. Unfortunately over Xmas I became Glutamine intolerant. I can handle 1gm max a day now. If I have over 10gm I gut full blown D and ill for a couple of days (bloating, the runs the lot). There’s a presentation by Kasia Kines that discusses clients she’s seen that have become intolerant.
So it was good but it always gave me headaches and nausea when I took it.
Megan Stevens says
It’s always helpful to hear testimonies. Thank you for sharing.
Vina Keaveney says
Thanks for this great post. I have the MTHFR genetic defect and as a consequence very poor gut function with neurological issues. Everything I looked at, all the “healing diets” recommended glutamine. I had read Dr. Natasha Campbell’s book “Gut and Psychology Syndrome” and for some of the reasons you mentioned she advises caution before adding bone broth because of the glutamine content. I can’t tolerate bone broth at all and had gotten so bad I started reacting to the glutamine in foods. It certainly shouldn’t be taken in supplemental form for a lot of people. You really have to consider the benefits and side effects of amino acids. They have the potential to hinder progress and even aggravate present symptoms. But it is so hard to find someone who even mentions potential negative reactions. I for one learned the hard way with this supplement. Thanks again.
Calogero Fiore says
Hi Vina,
I suffered taking Glutamine and collagen and bone broths but my symptoms dont seem neurological, my symptoms mimic relapsing polychondritis which is inflamation of cartilage in the body and a serious disease, my left ear but not the lobe become red as hell and burns for hrs, I get this with a fair amount of sugar too, with muscle meat or eggs no problem though just those bone broths, I wondered whether its the heavy metals in the bones that does it, one lady who said she cured herself of this disease said she went vegan and was healed so I tend to limit animal products, dairy and gluten.
Vina Keaveney says
Hi Calogero,
That’s interesting. I do believe it is the high concentration of amino acids that is the problem. Glycine, also found in high concentration in bone broth, breaks down to oxalic acid and I know i have major issues with that chemical. Thankfully, I resolved this issue by fasting and now that I have incorporated bone broths back into my diet, it has certainly aided my healing process. Going vegan would never be an option for me. Meat heals! Plants ‘cleanse’! I need nutrients in their most bio-available form, without all the anti-nutrients in plant foods. It is a myth bone broth is high is heavy metals. The heavy metal content of foods is largely unknown but kale, for instance is much higher in lead than bone broth! I believe it is essential to not only be gluten free, but grain free. Far too inflammatory and irritating to the gut. All the best with it.
Anwar says
Plz tell me how to heal leaky gut and leaky bbb without l glutamine and bone broth
Megan Stevens says
Hi Anwar, update (2026) follow the links at the bottom of the article to learn more about a diet low in vitamin A, copper and nickel, and what binders to take during the detox process. As you liver heals, so does your gut and brain.
Heather says
Thank you so much for this article! I have been doing GAPS now for 6 months for my ASD 15 year old son. He has had remarkable progress on the diet alone, but have been recommended over and over to try him on glutamine. I am always very hesitant to add or change his protocol, since we are seeing such positive results already. That being said, if there is more that can be done to help him, of course i want to do whatever i can. Yours was the only “con” article i could find in reference to glutamine, but also made the most sense. He already consumes bone broth at least 3 times daily, plus a lot of the other foods suggested. So with the exception of possibly adding more gelatin or collagen, i think we’ll just keep on with what we’re doing 😉 Again, thank you for helping me make an informed decision for my child. By the way, your whole website has been a Godsend through this GAPS journey.
Megan Stevens says
Great, Heather. Thank you for sharing! So glad the site is helpful. And Yay You! You’re doing great! 🙂 I hope healing keeps going great!!
Heather says
What are your thoughts on digestive enzymes in conjunction with GAPS? I searched your site, but didn’t find anything pertaining to them. I know they GREATLY help my 17 year old daughter with her IBS-D, but was wondering if it would help my son absorb more of the nutrients he’s ingesting. Also, thank you so much for your comment! So encouraging 🙂
Megan Stevens says
Hi Heather, I’m a fan of using digestive bitters, when needed. I like the one by HerbPharm the best; but there are a few good ones. Second to that, I like HCl with Pepsin, one with every meal that contains protein. They can be a necessary aid during the GAPS process and after. I prefer them to digestive enzymes, because they’re adjusting the pH of the stomach, but also positively affecting the liver, gall bladder, small intestine, pathogen issues etc. As far as your son not digesting all of his nutrients, we have had that issue as well, especially with my youngest. Cheers and blessings! (Or, here‘s how to make your own bitters.)
Mike Rioux says
Have you looked into turpentine? Their have been great results with autism.
MassiveQuantitiesofPie says
Are you recommending this person poison their child with turpentine because he’s on the spectrum?
Benni says
Bone broth and gelatin are byproducts of a very, very cruel and sick industry. Please know there are conscious, vegetable based alternatives! So many foods are pre and probiotic and gut healing… there is no need for this madness.
Jo Bean says
Seems somewhat irresponsible to be drawing widespread conclusions from a few things you’ve read, especially when pushing products. For example, the study you reference that indicates glutamine can help cancer cells proliferate was taken from a study on patients who already had cancer. Yes, it’s always wise to consider the other side of things and not assume any one supplement is a panacea, but to outright say that glutamine is NOT recommended is way out of your range of expertise, sorry.
MassiveQuantitiesofPie says
How else would you test a substance’s effect on cancer cells than to give it to people who already had cancer?
Glutamine has serious effects inside the body and the brain. That’s a fact. It might work out fine for many but it’s a very bad idea for anyone with a mental illness to take it.
pesh says
This is one of the worst articles about gut health i have ever read.
First – people that have problems with glutamin – it is not the gut – their problem is elsewhere
Glutamin is much better than collagen or gelatin because it is absorbed while gelatin or collagen if not digested will feed bad bacteria – putrefaction.
There are many people who eat broths and gelatin but never heal unlike people taking glutamine.
And to tell that glutamine is bad is like blaming peanuts for your peanut allergy. You just have to check reviews under glutamine on any site that sells it.
You can not heal using whole foods for many reasons – like low HCL – and for this reason – low HCL – when you eat meat it will putrefy and feed bad bacteria.
Ryan Michael Ballow – please show some evidence that glutamine feeds bad bacteria even if you have sibo – this can happen if you dont absorb it – but if you cant absorb amino acids then how are you live at all?
hamid says
I was suffering from brain fog for about 1 year. conventional medical approaches did not work. then i decided to heal my leaky gut. i used l-glutamine to heal my leaky gut but it is increasing brain fog.then i stop taking glutamine.
FC says
Green tea and other GABA inducers attenues glutamate toxicity, that’s why you drink green tea with your soya souse sushi.
Niya Ray says
When I go to test for food sensitivities using electro-dermal biofeedback technology, it always shows extreme sensitivity to Gluten, some other grains, MSG, L-Glutamine, gelatin, most protein (except some fish), most fats and anything with Dairy, some veggies and many fruits also. And I do have IBS and a leaky gut, anxiety and hypothyroidism also.
Chris Shelley says
Megan Stevens – Thank-you! thank-you! I can’t thank you enough for this post. I got online this morning looking for help since I couldn’t figure out why I am feeling so awful after trying out Glutamine. Last night I read to make sure to take it on an empty stomach – so I did,and couldn’t go to sleep, then finally with a lot of help from passionflower etc and just exhaustion fell asleep, but woke up feeling worse at 3 AM: nerves on fire, stomach/heart/head feeling like it was flying, headache, body aches, just feeling horrible.
I’d read so much good about Glutamine for the gut – I hadn’t seen anything negative.
Thank-you for being brave enough to post this most helpful information, against the popular stuff out there. Popular isn’t always truth! and everyone doesn’t always react the same!! (I’ve thrown out the bottle of glutamine)
Megan Stevens says
Hi Chris, I’m so glad this article was helpful! Thanks for your kind words. Blessings in finding better alternatives that help you in your wellness process! 🙂
Dominus Sylvestris says
I’m somewhat in agreement here. Too much glutamine spikes my anxiety and it’s very uncomfortable and counterproductive to healing. However, now I’ve incorporated lysine, citrulline, agmatine… and the anxiety can be reduced taking GABA, ashwagandha, etc. too.
MK says
I cannot take gelatin for religious reasons ( as the source can be Pork)
Any other solutions to heal leaky gut ?
Holly says
I was prescribed 10grams of L glutamine per day for leaky gut. I started slow at 3 grams. Within a week my fatigue was off the chart and I had a terrible eye twitch. I’ve been off it now for little over a day and haven’t fully rebounded. But getting better. There is no doubt it was the glutamine. My body has confirmed that this stuff isn’t good for everyone!
Megan says
Thanks for sharing your experience, Holly.
Heather Tasker says
I took l-glutamine for a few days last summer and it felt like I went back to eating gluten. My guts were upset and my joints very painful. Not a good supplement for me!
Megan says
Hi Heather, thanks for sharing.
Heather Tasker says
Thank you!
Cody Adams says
Thank you so much for posting this. I took l-glutamine in the advice that it can help heal my leaky gut/Crohn’s. But after an hour of battling it I had extreme anxiety. I thought I was losing my mind. Nice to know I’m not crazy lol.
Maya says
Thank you so much for the article!
Alex deJong says
Hello, great article. I recently went to a Naturopath and she told me to take 5gr three times a day of L-Glutamine but now I find my skin is more itchy. My gut does seem to feel better but I’d rather use an alternative.
Kristen says
Well I learned the hard way not to have glutamine with leaky gut. Two pound weight gain in two days when using it along with bone broth. On top of a steadily increasing weight thanks to all my food intolerances. I wish they would stop promoting this damn “supplement”.
Ch says
Here brief comment on part of the artical.
Glutamine is an neurotransmitter and can cause anxiety as the artical says. However there active pumps in the brain that remove unwanted proteins including glutamine so that a balance in maintained. The amount glutamine in the blood and in the brain is very different. Glutamine levels in the brain is controlled within a narrow range.
If someone has a hangover or eats to much sugar glutamine levels increase in the brain. Supplementing with glutamine has been shown to reduce sugar and alchohol craving. Most likely the brain can easily adjust over time to excess glutamine in the blood.
If you take glutamine while drinking it may reduced the hangover that you will get afterwards.
Bob says
You mean glutamate not glutamine. Glutamate is am excitatory neurotransmitter and glutamine is the amino acid precursor.
Chris M says
Several of the dangers of long-term use of glutathione could be true, but at the same time, long-term use of glutathione causes a zinc deficiency. Lack of zinc = probably all of those dangers of glutathione. Zinc is a very tricky mineral to absorb, considering it’s blocked by calcium; and many people don’t know about mineral interactions, supplement interactions, low stomach acid, phytates, etc.
What do you all think?
Petrus says
Supplementing with L-Glutamine… No thanks, no way — NOT if you are an “A” Blood Type. A good deal of the leaky gut problem (and many other health issues) rests in not eating the right diet based on your blood type. And Type A does best avoiding meat and animal by-products. Chicken and turkey are about the only (somewhat) safe meats for this type.
So, believe me — the blood type factor in dietary do’s and don’ts is the one thing that isn’t on the radar enough, and don’t believe those who say the “research isn’t in” or that’s it’s inconclusive. Look into the information for yourself and modify your diet. Some supplements can help, but even those may be subject to your blood type as well.
Brandon says
I came here searching about L-Glutamine BAD side effects .. an idiot doc prescribed to me a neurotransmitters complex supplement for anxiety and depression .. included Lglutamine .. taking in total 15 pills in 20+ days span and I had my worst year ever .. for sure caused of EXCITOTOXICITY .. and possibly by Phenylalanine and other EXCITATORY neurotransmitters. That idiot “doc” should had prescribed inhibitory neurotransmitters for anxiety . Please EVERYONE search the bad side effects of everything, prescribed Drug/Medication, Supplements , cause a great part of “doctors” are ignorants actually !!
Lynn says
Thanks for the information on your page. I’ve been searching for information on glutamine, as a recent hair analysis came back as having high levels of glutamine. While my glutamic acid and glutathione levels results were normal. I don’t take any regular prescriptions but I do take a probiotic and on occasion calcium supplement chews. I’m not sure why my glutamine levels are high. Diet? Underlying medical issue or problem? I’m also not sure if I need to be concerned about it? Any advice?
Lisa says
Have a look at Vitamin K2. I have read that calcium supplements can increase heart disease because the calcium ends up in the arteries. Vitamin K2 helps to shift the calcium into the bones and teeth, and should be taken with light from the sun (or vitamin D lamp). Worthwhile doing some research on this.
Beverley says
Interesting! I have SIBO and L Glutamine worked for a time but taken lately
it threw my stomach out of sink big time. This makes sense to me now,
Grateful for your input.
I guess we need to read ALL the info out there. Good and bad.
Bayliner says
L Glutamine is found in all foods..After intestinal surgery it was found to help in healing…at 1000mg per day…After a period of 30 days most patients are advised to reduce the dose until you then stop taking it all together. So just like taking any medicine you take it for a reason. Lets understand that . Boosting your intake for a short period of time after lower GI insults has shown to help many people..But does that mean you can then go on a Alcohol, Sugar or Junk food binge! A lot of factors here to consider before we throw L Glutamine under the Internet bus..
Chris M says
And to add to that, I have recently read that if combined with glycine, glutamine becomes stable.
yahoo finanza cambio says
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Heather W. says
Maybe someone can correct me if I’m wrong, but I believe this, as an isolated supplement was a topic in the video series The Truth About Cancer. A doctor discussed the isolated supplement as something very scary to fool around with due to the neuro effects.
Phill says
Nice article. Can I mix glutamine with collagen and lemon juice?
Pedro says
Thanks for the article!
A question.
I have some kind of histamine intolerance that makes me to have symptoms when taking veeery small dosage of glutamine. The same when taken commercial collagen.
How glutamine and collagen are relared to have that coincide ce?
Thanks
Sam says
I have healed my gut and taking 20g l-glutamine everyday…people follow dosage lable 5g/day …and it’s never work and someone like you spreading lie about supplements which is test on people with gut issues and success stories is much more on internet then your false claim..
Bob says
Everybody reacts differently. She is just pointing out that some people cannot tolerate it, I am one of them. Glutamine is a good supp for some as is NAC but some cannot tolerate them.
Jess says
Hi, Thank you for this article. I was prescribed by my naturopath to take this in powder form by Klaire Labs when my GI Map results indicated leaky gut. What I’m finding is it is making me feel nauseous, but not all the time. I am generally very sensitive – to drugs, coffee, alcohol, smells, etc. Have you heard of this side affect?
Thank you!
Jess says
Thank you!
Valerie Sotiropoulos says
Love glutamine it has helped me so much for years. I suffer from loads of pain and whenever I stopped taking it the pains return especially sciatica with a vengeance I am 63 and I swapped it for collagen and wow the pain came back worse than ever before!!! So went back to glutamine and pain is gradually going it also helps the lining of my stomach as have leaky gut and hiatus hernia due to a bodged operation. Also have to take at least 10g a day or does not work so well I have also noticed taking it with a little collagen helps as they compliment each other but collagen alone did nothing to help me and the pain and stomach issues were so bad even pain killers did not help so for me glutamine is a blessing sent from God.
Dumb people says
You guys are retarded
Started taking glutamine and it takes all the pain away if I get the dosage right
Especially paired with nac does wonders
Dorothy says
I’m wondering about L Theanine, an ingredient in a supplement we were considering, and it says it’s derived from a plant source of L glutamine. Would it be better not to supplement with this derivative?
Megan says
Hi Dorothy, probably fine in my book. L-Theanine is an amino acid known as the sunshine supplement. It promotes relaxation and happy feelings, often derived from the tea plant.
Dorothy says
Thank you, Megan.
Megan says
You’re welcome, Dorothy! 🙂
Amber says
Thank you for this information. I started on L-Glutamine five days ago, and have been having heart palpitations, chest constriction, shortness of breath, body aches and major anxiety. These symptoms are not normal for me. I’m so grateful to have found this article so that I understand what is going on and possibly why. I will discontinue taking it and re-evaluate how I feel. It’s hard to find info about these kind of symptoms related to this supplement. It’s the only thing in my health care regime that’s changed, so I suspected it may be connected. Thank you again!
Megan says
Thanks for sharing, Amber, and I’m so glad the article is helpful.
HealthAdvocate says
Dear Megan,
I have two questions regarding two of the bulleted points from your article, copied below:
“One study on oral hygiene and disease (1) shows that glutathione produces bacterial growth, proving it can become food for invasive pathogens.”
Should this say GLUTAMINE rather than GLUTATHIONE as producing bacterial overgrowth?
“Glutathione has also been linked to the thinning of gut lining when used long term.”
Again, was this an error – should it have stated that GLUTAMINE has been linked to thinning of the gut lining or is it factual that glutathione has been linked to thinning of the gut lining?
I just need to clarify as I has glutathione deficiency and often take supplemental glutathione.
Thanks
Megan says
Hi there, no, those are not errors. Glutamine is a precursor for glutathione and can be problematic for some people. That doesn’t mean that it will, but to proceed with awareness, caution, or to follow Paul Jaminet’s recommendation and avoid. So yes, he is saying that glutathione, taken directly or from glutamine, can also be problematic. What he recommends for glutathione is to take: “1 g taurine taken in the morning and 1 g glycine taken in the evening”. Happy to help and to clarify.
Marion Morgan says
I am in my first week of taking L-glutamine, a teaspoon 1/2 hr prior to a meal, X2 daily. Here is my experience:-
Various issues resulted in a Coeliac test, maybe a decade ago. I consumed more wheat products for this test (at enormous cost to my well being). I was declared negative! Much later, prolonged bouts of long lasting flu, thick mucus and night coughs – I stopped all gluten related food, more in desperation, not knowledge. A number of physical issues I had considered my ‘normal’ disappeared like magic, along with these battles. I never get a cold now. I still have sensitivities and may get phlegmy or perceive inflammation; no colds though for many years. Allergenic responses can be to natural food, as well as modern farming/g.m./preservatives etc, not to forget degradation of product, make this all complex and bewildering, for many. Periods of unexplained weight loss have occurred for me. Being of a keep-fit mindset, it seemed a good thing, Having had a sweet tooth in childhood, now curved, but to stopped, my current weight loss is severe. I am not diabetic. My general muscle mass has become changeable.
Seemingly impossible, one week into taking L-glutamine and my glutes are firming up; I walk a lot and had strong, buttock/calf/thigh-muscle mass, which disappeared around 2 yrs ago. I seek balance, not supplement addiction, but identifying nutrient needs and meeting them is intelligent. The contents here are noted. I must comment that the trials relied upon are by no means convincing. Different individuals have their own need, so this information about glutamine is of course important.
Thankx, eatbeautiful.net. Glutathione, I’d heard of, glutamine is new to me, but a health-food practitioner, suggested it to ‘plug’ leaky gut. My investigations aren’t over, but, it appears a good step, for me.
Debbie Walters says
I have taken l-glutamine in the past many times successfully. But I now have histamine intolerance and oxalate overload and can’t take l-glutamine any longer.
Megan says
Thank you for sharing, Debbie, and I’m sorry for those recent health developments. I hope you’ll find my articles on how I recovered from those same health issues.
Bob says
Wow you described me exactly. Glutamine wounds me up and so does any sulfur supplement like NAC. I do take Molybdenum which does help me clear the sulfur buildup. I do take a pro-GAD supp that helps with the Glutamate to GABA conversion. I also started taking Inositol and it’s really helped with any anxiety. Great article. Thank you.