If you do take probiotics are there any supplements that can help boost probiotics effects? In recent years so-called prebiotics have been touted for boosting levels of Lactobacillus and Bifidobacteria in the gut. It is quite clear that prebiotics (inulin, chicory root, fructo-olligosaccharides) can increase both Lactobacillus and Bifidobacteria, however it remains unknown if they are also promoting undesirable bacteria as well. There have been hints that they can. There are now two causes of concern for CFS patients and prebiotics – i. prebiotics have been shown to promote intestinal permeability, irritate the gut lining (this is a massive problem, especially when considering the new studies from Dr Michael Maes who documnented intestinal permeability in CFS) ii. prebiotics can increase the amount of lactate produced in the gut (now that we know there is already excess lactate production and/or inadequate lactate clearance, this is an obvious caveat). On a personal level your conjecture that fiber induced fermentation in the gut could be associated with increased anxiety and aggression was intriguing since I’ve always felt that ’edginess’ is a key factor in my version of ME/CFS. But how do fiber induced problems in the gut translate into central nervous system problems? A study by Dr. Shungu has suggested increased lactate production in the brain may be occurring in ME/CFS patients; could this have anything to do with lactate production in the gut? When too much fermentable fiber shows up in the large intestine there is a massive uptick in the production of D-lactate. Since, in CFS, we now know there is already over-production of D-lactate the blanket statements to eat more fiber may not be well suited to CFS. For example, animal studies show that excessive D-lactate production, due to excess fermentable carbohydrates showing up in the distant portion s of the gut, can increase aggressive an anxious behavior. It completely throws them off. The same phenomenon has been written up numerous times in cases of short bowel syndrome. These are individuals who have had a portion of the small intestine removed, they are more prone to the over-fermentation of fiber-rich carbohydrates in the large intestine and an excess amount of D-lactate is produced. They can experience brain fog, lowered mood state, hypothamic dysfunction and anxiety when transient elevations in D-lactate occur. Since we know that CFS patients have both bacterial overgrowth and excess D-lactate production (and/or lack of D-lactate clearance) a similar situation may be occurring. Ultimately, excess prebiotics and even excess Lactobacillus strains may worsen the situation in short bowel syndrome, and perhaps CFS as well. I was very interested in Dr Shungu’s work as well. It certainly suggests that if excess lactate is making it to the brain (and we already know that systemic lactate can cause anxiety in adults with no history of anxiety) it can have multiple implications. Obviously, we have just begun to scratch the surface of this research, however in moving forward we should be very selective of the stains we use for CFS clinical trials. Your statement that ‘fiber restricted’ diets can be helpful in this disease is a little jarring to hear given all the emphasis these days on high-fiber diets. You also noted that a fiber restricted diet cut the production of hydrogen and methane gas by more than half in one study. What is a restricted fiber diet look like? Are certain types of fiber worse than others? Yes, while most adults and children in developed nations may need more fiber, those of us with CFS may actually be adding fuel to the fire. An elemental (liquid food) diet has been shown to help eradicate small intestinal bacterial overgrowth and gut excess H2S production. At this point we need more concrete studies although the soluble fiber in oats, barley, rye and root vegetables will be more likely to fuel fermentation and increase lactate production. You noted that excessive fermentation in the large intestine can lead to the overproduction of lactic acid yet fermented lactic acid producing vegetable products such as sauerkraut, pickles and miso (as well as yogurt) are also sometimes recommended for gut issues. Do you recommend against using those products? No, generally these would be good choices if not in excess. There is a difference between foods that have been fermented, and foods that are awaiting fermentation by our own bacteria. Still, excessive dairy sugars arriving in the lower gut may be an issue and dairy has been associated with problems in short bowel syndrome with excess D-lactate production. If someone goes on a fiber-restricted diet how soon should they know if it is working for them? Within a few weeks What tests can patients take to assess the status of their small intestine with regards to bacterial overgrowth, hydrogen sulfide gas production, leaky gut and fiber problems? In addition to Dr K DeM’s exciting new H2S urine test, there is also a test for small intestinal bacterial overgrowth…it is called the lactulose-hydrogen breath test. Similar tests are available for assessment of intestinal permeability. In North America, Genova Diagnostics does the small intestinal bacterial overgrowth and intestinal permeability tests. There are blood tests for D-lactate; however, by the time a CFS patient sets up the testing the lactate may return to normal. That test is unique in that it is all about timing. Hopefully we will see some clinical investigations in CFS with patients consuming prebiotics and/or decent portions of fermentable carbohydrates and then evaluating both blood and urine lactate in the hours that follow. A study by Dr. Burnett several years ago suggested that chronic fatigue syndrome patients often suffer from ‘reduced gastric emptying’ it seems to refer to food products remaining in the gastrointestinal system for longer than normal. Would this contribute to fermentation and bacterial overgrowth problems ? It would certainly contribute to the upper gut symptoms after a meal. It also hints that there are electrical problems on GI tract in general. If there are any problems along the line, it can lead to stasis. We need more work in this area. What may be happening is similar to the folks with short bowel syndrome (although CFS patients may have a structurally intact small intestine, the SIBO may make it a functionally poor portion of the organ) where food material may be passing through the small intestine and then literally get “dumped” into the large intestine. When this happens with fructose, for those who do not absorb fructose well and it speeds through the upper gut, there is massive fermentation and mood related symptoms! One of the beneficial aspects of enteric-coated peppermint oil is that it helps regulate peristalsis. This is almost certainly why most of the dozen plus trials of ECPO (alone or combined with caraway seed oil) in IBS and functional dyspepsia have shown good results. Can one to some extent assess one’s bowel health simply by noting the consistency and quality of one’s bowel movements? That is could you say that someone who has one regular well formed bowel movement a day which was not accompanied by gas probably did not have problems with fermentation/hydrogen sulfide gas production? A regular, well-formed bowel movement will not exclude a potential problem with gut flora alterations. I would be much more inclined to work with the tests available. While these breath test and intestinal permeability tests are imperfect (and the new H2S test requires outside validation), they would tell us much more than bowel movements when it comes to the internal consequences of undesirable bacteria. I’ve always noticed that abstaining from food is helpful for me for short periods. On the converse many ME/CFS patients experience a considerable letdown 10 minutes or so after they eat. It seems that food does make a difference but this is occurring long before, one would think, food reaches the gut. Do you have any idea what’s going on here? A period of fasting may be lessening the load of lactate, propionate and H2S…but is not going to be the Rx here. I am not sure about the quick exacerbation of symptoms. I have heard from a number of patients that symptoms are worsened within an hour, and this may be indicative of the small intestinal bacteria having a feast in the upper gut. The ensuing increased intestinal permeability allows unwanted material to pass through the gut wall and fire up the flames of low-grade inflammation. For more on this topic I would urge visitors to your blog to further investigate the work of Dr Michael Maes and colleagues who have been doing great work in CFS, gut flora and intestinal permeability. Are there any books you recommend on irritable bowel syndrome or the gastrointestinal system for ME/CFS patients? I have yet to find one that is specifically suited to the needs and complexities of CFS. The problem is that CFS patients don’t have IBS per se, and the approaches don’t always apply. The findings in the CFS-GI connection (Drs K DeM, Maes in Europe, Dr Bested in Canada) are so new that a well-rounded gut-specific resource is still some distance away - hopefully soon, but we really need clinical trials to validate specific avenues of approach. As exciting as these gut findings have been, it is important to underscore that we are still on the bridge between hypotheses and true clinical guidance in CFS. Thanks Cort for your dedication and hard work to the amazing, resilient community of medical underdogs, the CFS patients.