As the Undoctored experience with both small intestinal bacterial overgrowth, SIBO, and our Lactobacillus reuteri yogurt grow, we are learning new lessons about the interaction between the two.
Recall that SIBO is a peculiar but exceptionally common situation in which unhealthy bacterial species such as E. coli, Shigella, Campylobacter, and Pseudomonas have proliferated, then ascended from the colon up the 24-feet of ileum, jejunum, duodenum, and stomach. Exposure to excessive quantities of sugar, glyphosate in wheat and grain products, drugs like Prilosec and naproxen, and antibiotics reduce the number of beneficial microbial species that allows unhealthy species to proliferate, adding up to trillions more bacteria that live and die in the 30-feet of your gastrointestinal (GI) tract.
It means that, if you underwent upper endoscopy and a sample of intestinal contents was obtained from the duodenum, it would be teeming with microbes, a place that should have few bacteria.
Enter L. reuteri, a unique microbial species carried by hunter-gatherers and most humans up until around 1960. Modern lifestyles have eradicated L. reuteri from the microbiome of most twenty-first century people, as only 4% of people continue to carry this species. You were supposed to obtain L. reuteri via breastfeeding as an infant and/or passage through your mom’s birth canal. You may have, if your mother harbored the species, but modern life has eradicated it.
L. reuteri has characteristics that make it important in our SIBO management efforts:
- L. reuteri is unique among probiotic species in that it “prefers” to colonize the upper gastrointestinal tract, i.e., the stomach, duodenum, jejunum, and ileum, rather than the colon as most other probiotic species do.
- L. reuteri is a vigorous producer of bacteriocins, natural antibiotics such as 3-hydroxypropionaldehyde that are effective against the bacterial species of SIBO.
- L. reuteri is probably a “keystone” species, i.e., a bacterial strain that supports the proliferation of other desirable bacterial strains. Just as mangrove trees along the ocean protect the coastline from erosion and provide a safe habitat for many species of fish and other animals, and loss of these trees would be catastrophic, so L. reuteri supports the proliferation of other healthy species. Without it and you have lost more than just L. reuteri.
But there’s an added twist that was proposed by one of our Undoctored Inner Circle Members, Ashraf, who, annoyed by blowing scores of 10 on his AIRE device despite three courses of herbal antibiotics, finally asked whether the upper GI-tract colonizing habits of L. reuteri could be responsible for yielding hydrogen gas. L. reuteri does indeed convert prebiotic fibers to hydrogen. Of course, hydrogen production per se is not harmful, but the timing of hydrogen gas release after consuming prebiotic fiber acts as a “radar” for locating where in the GI tract hydrogen-producing microbes are dwelling. Ashraf and some others experiencing the same dilemma stopped the L. reuteri yogurt for two weeks and re-tested: lo and behold, negative H2 gas readings.
Could the loss of L. reuteri from modern guts be at least part of the reason for the explosion in SIBO? Could it also be responsible for the surge in (pre-pandemic) social isolation, suicides, and divorce? I believe that we have tapped into concepts that hold enormous potential to change our health and life.