S. Boulardii is especially a gem if you've a Histamine intolerance like me and can't take any fermented foods and/or most probiotics.

This isn't a species that is talked about much on the forums.

S. Boulardii is a transient yeast that is not a normal constituent of the microbiota. It gets flushed out within days of discontinued use. Although, it is known to stimulate Secretory IgA.

Lactobacillus Reuteri on the other hand is one of the few and only natural inhabitants and permanent colonizers of the GI system of humans among all the known probiotic organisms. The gut is reuteri's natural habitat, so it's well suited to compete and thrive in that environment. What's interesting about L. Reuteri is that it produces reuterin the broad-spectrum antimicrobial substance that kills other competing microbes. It colonizes the ileum and duodenum primarily (lower and upper gut, respectively).

Reuterin is thought to act as an antimicrobial by modifying thiol groups and inducing oxidative stress (free radical damage) in the target cells of competing organisms, killing them.

Among the lactobacilli, reuteri appears to be an organism that stands out among them due to various properties of the species it's more potent than others. And the fact that it colonizes humans naturally suggests a valued use or need for it. Not everyone carries it though.

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Side note: things like this are one of the reasons why we will probably never identify some standard microflora for humans. It depends on too many variables. It's composition changes with diet, method of birth, whether breast fed or not, and geographic region among others. Even though there may not be some standard by which all people can be measured, it's probably possible to identify dysfunction within the microbiota and uproot those aspects to optimize health.

But since our understanding of the microbiota is so new and very incomplete it seems we're still a loooong way away. In a lot of studies, the authors even admit that most microbial inhabitants aren't even identified or there is great difficulty in culturing or isolating them due to their anaerobic nature. So not only do we not know everything that's in there, we also don't know what role they serve whether immune related, metabolic or otherwise.

And aside from the bacterial side of things, there's also the gut "mycome" or the yeast and fungal aspects to the microflora. And it's hard to come by research on those as most things seem to focus on bacteria - typically the lactobacilli and bifidus.
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Among humans and birds its been identified as one of, if not the only, near universal inhabitants or symbionts.

It's thought that the symbiotic relationship between humans and the lactobacilli largely revolved around this relationship with reuteri. Reuterin kills other microbes but allows other lactobacilli to live. Other LAB seem to have a tolerance to it to some degree, but it's possible for the species to secrete enough reuterin to eventually kill reuteri itself.

That said, I've used both. S. boulardii caused some particularly nasty cysts.

Just don't expect miracles from either of them in terms of acne. Also, if you're looking for reuteri, it almost never occurs in any supplements you can buy you won't find it in yogurt, kefir, etc. You would think that such a cornerstone species in the development of the immune system would be more readily available but it's not. BioGaia does make a liquid for infants but other than that, it's not very common. Their strain/species has also had genes removed, as reuteri normally has genes encoding for resistance to vancomycin.

18 hours ago, FvckAcne said:

This isn't a species that is talked about much on the forums.

S. Boulardii is a transient yeast that is not a normal constituent of the microbiota. It gets flushed out within days of discontinued use. Although, it is known to stimulate Secretory IgA.

Lactobacillus Reuteri on the other hand is one of the few and only natural inhabitants and permanent colonizers of the GI system of humans among all the known probiotic organisms. The gut is reuteri's natural habitat, so it's well suited to compete and thrive in that environment. What's interesting about L. Reuteri is that it produces reuterin the broad-spectrum antimicrobial substance that kills other competing microbes. It colonizes the ileum and duodenum primarily (lower and upper gut, respectively).

Reuterin is thought to act as an antimicrobial by modifying thiol groups and inducing oxidative stress (free radical damage) in the target cells of competing organisms, killing them.

Among the lactobacilli, reuteri appears to be an organism that stands out among them due to various properties of the species it's more potent than others. And the fact that it colonizes humans naturally suggests a valued use or need for it. Not everyone carries it though.

---

Side note: things like this are one of the reasons why we will probably never identify some standard microflora for humans. It depends on too many variables. It's composition changes with diet, method of birth, whether breast fed or not, and geographic region among others. Even though there may not be some standard by which all people can be measured, it's probably possible to identify dysfunction within the microbiota and uproot those aspects to optimize health.

But since our understanding of the microbiota is so new and very incomplete it seems we're still a loooong way away. In a lot of studies, the authors even admit that most microbial inhabitants aren't even identified or there is great difficulty in culturing or isolating them due to their anaerobic nature. So not only do we not know everything that's in there, we also don't know what role they serve whether immune related, metabolic or otherwise.

And aside from the bacterial side of things, there's also the gut "mycome" or the yeast and fungal aspects to the microflora. And it's hard to come by research on those as most things seem to focus on bacteria - typically the lactobacilli and bifidus.
---

Among humans and birds its been identified as one of, if not the only, near universal inhabitants or symbionts.

It's thought that the symbiotic relationship between humans and the lactobacilli largely revolved around this relationship with reuteri. Reuterin kills other microbes but allows other lactobacilli to live. Other LAB seem to have a tolerance to it to some degree, but it's possible for the species to secrete enough reuterin to eventually kill reuteri itself.

That said, I've used both. S. boulardii caused some particularly nasty cysts.

Just don't expect miracles from either of them in terms of acne. Also, if you're looking for reuteri, it almost never occurs in any supplements you can buy you won't find it in yogurt, kefir, etc. You would think that such a cornerstone species in the development of the immune system would be more readily available but it's not. BioGaia does make a liquid for infants but other than that, it's not very common. Their strain/species has also had genes removed, as reuteri normally has genes encoding for resistance to vancomycin.

There are a few opportunities to contribute to the Human Microbiome Project's expanding research database. American Gut and British Gut, off the top of my head. They are always posting more on the Quantified Self blog too.

http://humanfoodproject.com/americangut/

I'm aware of the various projects out there studying the microflora.

Maybe I've already posted this, but I was going to suggest that a thread be created on the topic of microbiota sequencing where something like 100-200 people shell out the 80 bucks or whatever and have their gut sequenced so that the results can be posted here. Those other projects are useful, but they offer no insight into acne specifically. Since it's probably safe to assume that anyone on these boards is dealing with acne, which is what we're interested in, at least that would give us a better idea of what sort of organisms we're harbouring and in what sort of ratios. I'd be especially interested to see some graphs and results from those with severe acne.

That would probably be more useful than another thread devoted to bitching about Accutane or something similar.

There's always gonna be that one dude with nothing but candida in the gut, but eh it's worth a shot. Don't worry bro, we'll never see your face.

I completely agree. But to be honest, from what I've read online, a lot the results that American Gut have returned have been fishy--sort of like when it comes to testing for food sensitivity, where results differ wildly from lab to lab. For that reason, I've wanted to get a thread going about imperative gut tests for skin issues like acne, eczema, etc. Everything from the best methods for stool analysis to SIBO breath testing, to organic acid profiles, and how to determine if any other panels are necessary (like a DUTCH hormone). Ideally, how to get the best gut labs for your buck when you're on a budget. And maybe resources for learning how to analyze your own labs when you can't afford a functional practitioner for diagnostics, and how to put together basic treatment protocols for different gut disorders.

...a lot the results that American Gut have returned have been fishy--sort of like when it comes to testing for food sensitivity, where results differ wildly from lab to lab...

I don't doubt it. The point is to get some idea of what your flora looks like. Otherwise there's no knowing a lot of stuff, like whether you're harboring pathogens, whether you're skewed in favor of Firmicutes rather than Bacteroides, etc. I'm fully aware that you can't go searching for a needle in a haystack with an array of such results without having some trail of thought as to where the problem lies.

You also have to remember that flora changes in response to diet. It's possible the results from different labs were the result of a change in dietary habits among the participants. There's no way of knowing really, unless the sample for both labs was taken at the same time. Different species use different substrates to fuel their growth.

Also, the problem with stool tests is that they are unlikely to reveal too much in that what it reflects is likely what is found in the lumen of the intestine and not necessarily what is attached to the gut wall. I suppose it's possible that what remains "higher up" in the gut may not always show up. But if it turns out you've got some 12-foot suckers livin' large in there, maybe that's what you're hoping for heh.

Overall though, inaccurate results is a very real possibility. This area of science is very new when you consider the grand scheme of things and there's just not too much that is really known. But already, it seems we've championed how to destroy it quickly though.

More to say but I'll cut this post here.

It really depends on the kind of stool analysis you run. Culture-based methods are the most accurate and comprehensive, imo. While I don't agree with Chris Kresser on everything, he has one of the keenest minds for functional diagnostics in his field. I tracked down a podcast of his where he provides a detailed overview of his choice gut tests, and since I don't think I could describe it any better, I'll just share the transcription from that portion of the interview:

"There are a lot of different ways to test the gut, but the three things that I consider to be important are a stool test, a breath test for SIBO, and then a urine organic acids profile that looks at certain organic acids that are by-products of bacterial and fungal metabolism, so they can indicate bacterial or fungal overgrowth in the GI tract.
In terms of stool tests now, Im currentlythis changes as I learn more and as new information comes to light. I used to run the Metametrix stool panel, but Ive lost confidence in that after I read a study that didnt mention Metametrix by name, but I think it was pretty clearly about Metametrix. After reading the study, which assessed the accuracy of the DNA PCR method that they were using, I lost confidence in it. Then Metametrix was purchased by Genova. A whole bunch of stuff happened there. So Im currently using the Doctors Data Comprehensive Stool Analysis with three samples. Its a combination of stool culture, really advanced stool culture method, and something called the MALDI-TOF method, which stands for matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Its a proteomic method of identifying bacteria and yeast. It works by measuring the unique ribosomal protein fingerprints of microorganisms. Then they compare the spectra with a reference database for verification and identification. Its a lot more sensitive than many other technologies. They can identify over 1,200 species of bacteria and yeast. Its used by NASA, I believe, to detect microorganisms in launch vehicles. It was ranked 3rdlast year in the Cleveland ClinicsTop 10 Medical Innovationslist, which is a list of medical innovations that will improve patient care. I like it because it also has other helpful markers. Its a stool analysis; its not just looking for parasites, yeast, and bacteria. It has some inflammatory markers like lysozyme and lactoferrin. It measures stool pH; secretory IgA (SIgA), which is a marker of gut mucosal barrier integrity; short-chain fatty acids like butyrate; beneficial bacteria; and some other interesting stuff. We also sometimes use BioHealth #401H, which is another culture-based stool method, and sometimes well run them together side-by-side.
For organic acids, we tend to use either the Genovaor former MetametrixOrganix Comprehensive Profile, or the Organic Acids Test from Great Plains Laboratory. This is probably, if I had to choose one of my top three tests, I would say urine organic acids is up there. Thats because you can learn so much not just about the gut, but organic acids are also by-products of cellular metabolism. There are all these cycles in the body. Things tend to kind of go around in a cycle. Getting from one step of the cycle to the next step requires an enzyme, to convert one metabolite to the next metabolite in the cycle. Each of those enzymes requires certain nutrients to function properly. So if a nutrient is deficient, that cycle will not complete and youll get a buildup of the metabolite or organic acid thats at the previous step of the cycle. That spills over into the urine and you can see it show up in the urine. Then that can give you some information about where these cycles are broken and whats happening in terms of metabolism, cellular energy production, fatty acid metabolism, carbohydrate metabolism, neurotransmitter breakdown metabolism, detoxification, methylation. One of the most sensitive markers for vitamin B12 deficiency is methylmalonic acid. Thats an organic acid thats on this test. Formiminoglutamic acid (FIGLU) is probably the most sensitive marker for folate deficiency, for tetrahydrofolate deficiency. Thats on this test. So you can learn a ton of stuff on these organic acids panels. Unfortunately, theyre not very easy to interpret for patients. Its definitely something you need training and education about, and its something that your doctor or practitioner can help you interpret, but not something thats too easy to figure out on your own.
Then theres the SIBO breath test. We use the one from Genova. Weve used also one from Commonwealth Labs as well, but we prefer the one from Genova because I think its more accurate in reporting methane, which we talked about on a previous show. And this is one of the ways to test for bacterial overgrowth in the small intestine. Its a good test overall. There is potential for false positive and false negative, so you cant rely on SIBO breath test results alone. But when its combined with the organic acids and the stool test, I think thats a really great combination for assessing gut health."

Just want to add, I don't know if this was a slip-up on Chris' part or if he just knows something I don't on the matter, but it was actually my understanding that while there are sometimes false negatives on SIBO breath tests (which is why if the symptomology is there you still want to implement a treatment protocol to be safe) , there aren't a great many false positives.So I'm not sure what he means by that bit at the end there...