Leah:
Hello and welcome to the Ideal Nutrition Podcast. I’m Leah Higl and I’m here with my co-host Aidan Muir and today’s episode is all about L -glutamine supplementation but particularly in the context of gut health. So giving a little bit of context for glutamine and what it is. So glutamine is the most abundant amino acid in the body. It is also the primary fuel source for the cells lining the intestinal wall which is why it’s often brought up in the gut health space.
So theoretically, this does help things like regenerating gut cells and tightening openings along the intestinal wall, which can also be referred to as the tight junctions. So for example, reducing overall intestinal permeability is something that is linked to glutamine and glutamine supplementation in this particular space. And that can also be referred to as quote on quote, leaky gut but just kind of preferencing there that this is not a medically used term, but it’s something that you will likely see in the gut health space if it’s something that you are looking into.
So there are quite a lot of conditions that are linked to some form of increased intestinal permeability. Whether this is a chicken or an egg scenario is like a whole other conversation, but things like inflammatory bowel disease, IBS and a variety of other conditions that are gastrointestinal related have been linked to, like I said, increase in intestinal permeability. And it’s because of this that there is some potential for glutamine supplementation in that context, as well as things like potentially reducing inflammatory processes as well.
Aidan:
So since we’re talking about glutamine for gut health and whether or not it is either helpful or it works, I guess one good starting point would be defining what would we consider working to mean. And the easiest way for us to measure that is measuring symptoms. Does it help improve symptoms of some of those conditions like irritable bowel syndrome or inflammatory bowel disease? There’s other stuff that is obviously relevant, but it’s harder to measure is whether it’s improving some aspects like tight junctions, which could then potentially play a role in things like improved immune function. Like you could see how it could turn into kind of an endless list of stuff. But keeping it simple, think for the sake of this, we’re going to start by just largely focusing more on the symptoms side of things because that’s really easy to measure.
Leah:
So going through the research in this space. So we’re to talk about three studies that were pretty easy to find. There’s not a whole lot of research in this space, but I think going through these briefly does kind of set the picture a little bit. So the first study was eight weeks of glutamine supplementation in those with post-infectious IBS. And this had over 100 participants involved. And there were actually significant improvements in symptoms and intestinal permeability in just under 80% of participants supplementing glutamine versus just shy of 6% of those in the placebo group.
So some pretty big discrepancies there that would show that potentially glutamine supplementation was a positive thing in this particular context. The second study added glutamine or a placebo on top of a low FODMAP diet. So 88% of the people in the glutamine group experienced significant improvements versus 60% in the placebo group. So overall, we know like the low FODMAP diet does generally do a pretty good job at addressing IBS in most people so we would expect that the results either way would have been pretty decent but there was that slightly larger improvement of the glutamine supplementation group in combination with the low FODMAP diet which can also be seen as quite interesting.
The last study looked at glutamine versus whey protein for IBS symptoms. Now in this particular study glutamine did outperform the whey supplement for improvements in overall symptoms. Although we wouldn’t really expect whey protein to be doing much. It doesn’t really make sense for that to be making any overwhelming improvements from an IBS perspective. But it does get us past any of the, guess, pushback of can’t we just eat more protein? If we’re looking for this specific amino acid, what happens if we just increase protein intake and therefore we have an abundance of amino acids?
So it does like debunk that logic a little bit. So figured that was worth putting in here as well. Now, the final thing I’m going to touch on from a research perspective is particularly looking at IBD or inflammatory bowel disease and glutamine supplementation. So we found a systematic review from 2021, which included seven relevant studies. The researchers found some positive stuff. So like one study found a reduction in intestinal permeability, but that specific one didn’t actually measure kind of outcomes and symptoms. Two studies had slight reductions in oxidative stress and inflammation, which is interesting, but the overall average findings were that there was no difference in disease activity or progression with glutamine supplementation.
Aidan:
Can I just let you go there and just cover research.
Yeah, I figured it was just easy to cover all that in one big chunk.
Aidan:
That was good. I’ll give my interpretations and any extra thoughts on this. So the first thing I’ll start with is if somebody was listening to this and like, I do want to take this myself. The standard dosage is 15 grams per day split over three dosages throughout the day. So five grams three times per day. That is a little bit more difficult than a lot of other supplements. A lot of other supplements you can just have once per day. So that’s just a tiny barrier there. But if somebody wants to take it and it kind of makes sense. It’s not too hard to do that. So that’s how you would take it.
My general interpretation of that research and also my own thoughts are the mechanisms make sense and I can see potential for it. The IBS stuff in particular looks very promising based on limited research. This is one of those areas that I find interesting being like, if no one else is around and I just saw this research by myself and I never heard anyone else’s opinion and then tried to make my own interpretation, would I be like, this makes sense. Everyone who has IBS should have a crack at trying glutamine. I don’t know, but I don’t see many other people in the evidence-based space kind of pushing it super hard. And the other question that I’ve kind of got is why is the research so limited still if it’s this effective? Like, why do we only have three or maybe four studies on this topic when it’s 2024 and research started a long time ago? So I’m still a little bit skeptical based on a bunch of those reasons. So it’s not my go-to recommendation, although I do see promise in it.
The inflammatory bowel disease stuff doesn’t look as promising, but I’m also quite open to there being individual variation. Like if somebody had inflammatory bowel disease, they tried it, they swear by it. I’m like, probably continue taking it. Like I do see the logic there as well. And there could also be heaps of those more broad gut health benefits. For example, like what I talked about earlier about being like if it helped with these tight junctions and stuff like that, theoretically that should carry over to getting upper respiratory tracts less freak tract infections less frequently, like just getting sick less frequently in general. There could be a bunch of potential benefits if a lot of this stuff does carry over as well.
Leah:
This has been episode 167 of the Ideal Nutrition podcast. If you haven’t yet left a rating or review, it would be super greatly appreciated for you to do so, but otherwise, thanks for tuning in.