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Dr. Logan on H2S, Fiber the Right Probiotics and Much More: Part I


Phoenix Rising Founder
Check out this very interesting interview with Dr. Logan as he comes out with some surprising recommendations on probiotics and the role fiber may play in ME/CFS

Dr. Logan is a board certified naturopathic physician who graduated magna cum laude from the State University of New York. An invited faculty member at the Harvard School of Continuing Medical Education and published researcher he is the author of “The Brain Diet” and the co-author with Dr. Alison Bested of a recently updated book on chronic fatigue syndrome (ME/CFS) - “Hope and Help for Chronic Fatigue Syndrome.”

He was willing to follow up a substantial comment he made to the “H2S Creator Speaks” blog with this full interview.


A good number of chronic fatigue syndrome patients do experience gut pain but gut pain has never been considered the main or even a main symptom of the disease. It’s easy to see how something like there irritable bowel syndrome could emanate from the gut but given the sometimes enormous debility found in this disease shouldn’t we be in a lot more gut pain than we are if this disease is indeed centered in the gut? The gut is after all a very sensitive area is it not - it doesn’t take much to make gut problems very obvious to the person suffering from them.

Indeed gut pain is not chief among the constellation of CFS symptoms. Yet the vast majority of CFS patients do experience some degree of gut related symptoms and indeed there are many other gastrointestinal (GI) signs and symptoms in CFS that are not pain-specific. For example, alternating constipation, diarrhea, bloating and so-called functional dyspepsia (upper GI discomfort soon after meals) may not involve significant pain per se, however they indicate that not all is right in the GI tract.

It is also true that there may be issues with certain gut bacteria that, while producing no overt gut symptoms, they are still capable of provoking a body-wide immune response and intestinal permeability. From animal studies, we know that even a tiny amount of undesirable bacteria in the gut, at levels not even high enough to cause an overt immune response, can activate brain areas involved in emotions and ultimately influence behavior itself. While we are a long way from confirming that CFS is centered in the gut, early suggestions indicate that gut microbes may be the tail wagging the dog.

On another very basic note - if we are all producing enough hydrogen sulfide gas this disease shouldn’t we all be belching and otherwise releasing enormous amounts of rotten egg smelling gas?

No, not necessarily. It would only take miniscule amounts of H2S gaining access through the gut wall to cause fatigue and a host of other brain and body-wide symptoms. Small amounts of H2S can cause cognitive difficulties, and of particular interest to CFS symptoms, problems with tuning out unwanted environmental stimuli…the sort of “tired but wired” symptoms of CFS. Normally we can clear H2S quite efficiently, breaking it down with enzymatic activity and releasing it through the lungs. Yet there are many unknowns about H2S, including the amount of gut H2S the normal person can tolerate. In addition to the emerging work from Dr K DeMeirleir indicating that there are elevated H2S-producing gut flora in CFS, it may also be the case that in CFS there is a deficit in H2S disposal.

A common remedy for bacterial overgrowth in the gastrointestinal system involves antibiotics. Yet antibiotics, paradoxically, are sometimes blamed for setting the stage for bacterial overgrowth in the first place. Many people are not surprisingly skeptical about taking antibiotics because of this. How do you go about ensuring that you’re not just making the problem worse?

Indeed, there have been studies showing that antibiotics have reduced small intestinal bacterial overgrowth (SIBO) and improves a variety of symptoms (including brain-related symptoms) in CFS and fibromyalgia. Yet, these are very small studies of small duration. What happens when the antibiotics are stopped and the patients are followed in the long term? We do not know. Given that antibiotics and overuse of acid-blocking medications set the stage for SIBO, I would be inclined to worry about using antibiotics as a means of clearing SIBO. I would be more inclined to use probiotics and enteric-coated peppermint oil.

There are quite a few different kinds of probiotics on the market that feature different kinds of bacteria. Are there certain kinds of bacteria that may be more helpful for the kinds of gastrointestinal issues that chronic fatigue syndrome (ME/CFS) patients face?

Yes, the benefits appear to be strain-specific. If it is for symptoms that resemble that of irritable bowel syndrome (IBS) then I would suggest 2 strains of bacteria that have been shown to be helpful for gut-related symptoms – Align (Bifidobacteria infantis 35624) and LactoFlamX (Lactobacillus plantarum 299V). In our University of Toronto study, we used a probiotic made by the Japanese company Yakult. The strain, Lactobacillus casei Shirota had been found previously to improve mental outlook in healthy volunteers who had the lowest baseline mood scores. It also lowers propionate production in the gut.

Recently propionate has been the focus of research in autism; once it gains entry to the brain, it can alter behavior. It is too early to tell, however I feel that bifidobacteria strains such as Align will become the probiotic of choice for CFS. Align has been shown to reduce inflammation systemically, beyond the gut. It also does not contribute to the lactate load in the gut. What was not really emphasized in the reporting of Dr K DeMeirleir’s research is that his team also found elevated lactate producing bacteria and certain Lactobacilli are major manufacturers of D and L lactate.

If I understand you correctly its possible that strains of Lactobaccilus bacteria that are frequently found in probiotic preparations could exacerbate lactic acid production. Apparently Lactobaccillus acidophilus turns sugars into lactic acid.

Yes, but not all Lactobacillus strains produce the undesirable D-Lactate (for example, the well-researched Lactobacillus GG does not produce D-Lactate, but most strains of Lactobacillus have not been investigated for D-Lactate production. Its time to map that out properly).

It’s generally true that L.acidophilus does turn sugars into lactic acid, but not all Lactobacillus strains produce the D-Lactate; the L-Lactate can be cleared with a fair amount of ease by most.

Do you recommend staying away from the traditional formulations (L acidophilus)?

Most probiotics marketed under the umbrella term “acidophilus” have not been researched for health outcomes (let alone stability!) and we have no idea of their D-Lactate potential. It is known from studies in short bowel syndrome that unspecified strains of L. acidophilus can be major promoters of D-Lactate.

Kefir has a different bacterial makeup than yogurt. I did read that kefir grains make it deeper into the gut. What about kefir?

Great question! There have been two studies that have looked at D-Lactate production in fermented milk, commercial yogurts and kefir. Interestingly the kefir did not form D-Lactate, yogurt had high concentrations of D-Lactate (over 40%).

When you get to the store shelf there are probiotics that don’t need refrigeration, that do need refrigeration, that have X million or even billion bacteria ‘at the time of bottling’, that are in liquid or capsule form, etc. Dr. De Meirleir some years ago stated he was simply looking for a probiotics that was strong enough to fit ME/CFS patients needs. I noticed that Prohealth recently advertised a product that has over 50 billion bifidobacteria organisms in one capsule (at over a dollar a capsule). Do you have any advice to offer on specific types of probiotics for chronic fatigue syndrome (ME/CFS) patients?

Until the research shows otherwise I would choose Align for the reasons cited above. There are very good clinical studies to support the product in IBS.


Senior Member
I read part 2 of this earlier, not realizing I'd missed part 1. :)

Man, this guy is interesting, but speaks simply and clearly enough for someone like me who does not have a strong science / medical leaning.

His direction sounds promising to me. Really promising.


Phoenix Rising Founder
Dr. Logan Replies to Comments on His Interview

Dr. Logan just posted a substantive reply to some of the comments from his interview on 'Bringing the Heat'

Fructose and Powerfoods - Yes, the powerfoods section listed on my website is directed at brain health for the general population and is definitely not a CFS-oriented list. I would concur that too much fructose can cause problems. Dr Max Ledochowski has authored 4 or 5 studies on what happens when fructose escapes absorption from the small intestine and gets dumped into the colondepressive symptoms, brain fog and much lower blood tryptophan levels. Correcting this via a low-fructose diet has been shown to improve mood etc. Interestingly, only about 1/2 of those with fructose malabsorption present with the overt gut symptoms.

Diet and Fruits - My only concern with removal of all fruits is that we also take away much needed dietary antioxidants from the deeply colored berries. Blueberry and bilberry actually have anti-microbial properties that may be to the advanatge of CFS patients and cherries have significant anti-inflammatory activityCFS patients are under increased oxidative stress, have lower levels of antioxidants due to the high demand, and in most studies, dietary antioxidants win vs. those from supplements. Consideration of some very small servings of berries is still warranted in my opinion.

The other concern with nuts, yes, absolutely no doubt they can be a source of sensitivity.

Candida and yeast cant be ruled out of this emerging equation of gut flora. Over the years the Candida story has been, in my opinion, over-played. Still, there was a study in the journal Family Practice in 2001 which showed that in adults with unexplained medical conditions (symptoms typically over-lapped with CFS) Nystatin was helpful. There were significant improvements in anxiety, cognition, depressive symptoms and insomnia. Recently Dr Evengards team in Sweden found that Candida levels are much higher in stool during the early stages of CFS and are lower when patients are in remission. Since we know that stress and antibiotics can increase Candida in the gut, it possible that once established, it becomes a secondary contributing factor.

- The dose used in the Sullivan probiotic study was 10 to the 8th power CFU twice dailythis was not a particularly high dose. The VSL#3 mentioned has a massive 450 billion CFU per sachetand it is the kitchen sink of a variety of different strains. It may help some, however I know of cases where anxiety increased after taking the product, it may be a D-lactate connection.

Gut Ph and D-Lactate - As Cort knows, we had this interview before the full text of the Dr K D paper on D-Lactate bacteria and CFS was released. Within the paper they note that alkaline therapy might be a future Rx in CFS. It would seem to make sensewe have high levels of acid-producing bacteria so it would appear rational to increase the pH and make it more alkaline.

However, the gut is a complex environment and a study by Jiang in Digestive Diseases and Sciences (1997) showed that raising the gut pH in the alkaline direction increases D-lactate production. In the same study they also showed that if you really want to lower D-Lactate production, add Bifidobacteria to the mix. Bottom line, we have much to learn about gut pH.

It has been shown since the 1920s that oral alkaline solutions can encourage small intestinal bacterial overgrowth and subsequent intestinal permeability (Arnold. Am J Hygiene 1928). Since CFS patients have both SIBO and intestinal permability, it is highly doubtful that alkaline solutions will be the answer.

No financial ties
- I should have said that I have no financial ties to Align or any other probiotic company.