The Mayo Clinic published findings in August 2018 that showed a high correlation between the bacteria Phascolarctobacterium and weight loss success, while the bacteria Dialister was associated with weight loss failure (https://newsnetwork.mayoclinic.org/discussion/makeup-of-an-individuals-gut-bacteria-may-play-role-in-weight-loss-mayo-study-suggests/).
Mayo is substantially behind the times in this area of research, since Scientific American covered multiple studies indicating something similar with regard to a suspected balance between the phyla Bacteroidetes and Firmicutes as far back as at least 2014 (https://www.scientificamerican.com/article/how-gut-bacteria-help-make-us-fat-and-thin/). And I’ve been writing about this since 2012 (https://www.elev8wellness.com/wellblog_best_nutrition_training_coaching_experts/your-gut-is-why-you-think-that-way).
In fact, we’re currently awaiting results from a human trial on FMT transplant at the Massachusetts General Hospital (https://clinicaltrials.gov/ct2/show/NCT02530385) specifically regarding if you can just put “lean-producing” bacteria in an otherwise fat-gain-propensity person and influence body composition.
I’ve been thinking about this for a long time. Interestingly, the Journal of Nutrition published a paper in 2009 by researchers who hypothesized fiber would make specific alterations in bacterial communities within our digestive tracts (https://academic.oup.com/jn/article/139/9/1685/4670531). If you pay close attention, you’ll find they sequenced the same Phascolarctobacterium which Mayo thinks may make us lean. Phascolarctobacterium (or P.faecium for short) is actually part of the Firmicutes phylum.
Efforts to term one strain or one group or one phylum of microbes as beneficial have fallen flat. At one point, it appeared Firmicutes may make us fat. At another, it looked like Bacteroidetes had higher associations with metabolic disease. Probably, we need very complex ratios which the human brain won’t likely sift. We’ll need something on the order of weather modeling super computers.
That said, there is ample evidence that fiber does indeed bring about changes in microbes which at this time appear mostly beneficial. The National Academies, AMA, World Health Organization, CDC and others have so far been unable to narrow down to an exact recommendation. Everyone agrees that we need fiber. We need enough to continue feeding beneficial microbes. We need enough to support the balance of symbionts which direct our health. In a deep dive on the literature, there’s evidence 25+ grams per day helps. it appears we’ll be trending toward a grams per kilos of body weight recommendation. I think it’s safe to surmise that since average American intake is 5-15 grams at best, and we’re unhealthy on average, the 25+ number is well-founded.
Somewhere around 1989 I read a few books which sparked an idea in me which was science fiction at the time, an idea that other life forms could be used to direct human health. I wondered if we could use microbes in a way to support ourselves the same way we had domesticated larger animals to the progress of mankind. In one of the books, I read about the infamous 1950 experiment of Miller and Urey, wherein they tried to lend experimental support for the possibility that the primordial soup theory was viable. Though they failed completely and no one has made any progress in the 7 decades since (austere chemistry with our guidance can’t produce a proto-self-replicating RNA or protein, let alone life; and the prevailing belief about early Earth atmosphere is set on a different group of gases than Miler and Urey used), the author was musing about the complex intertwined chemical and biological relationships which must’ve existed on the Earth then up to now. That is, everything influences everything else. What gases were present would’ve dictated what chemical reactions were possible. What reactions occurred would dictate what lifeforms were possible. The kingdoms would’ve and still do affect each other, leading to phyla interactions, and so on.
There’s this idea that the atmosphere and/or the oceans have a massive solution which can concurrently conduct trillions of “experiments”. This isn’t only a pathetic equivocating apologetics effort on the part of people who can’t let go of the abiogenesis fiction. It’s a reality that there are endless interactions and reactions which produce all of this stuff around us that we call life.
In human disease models, primates make for terrible test subjects. Rodents give us actionable information about drugs and disease because they have been living with us and sharing similar microbes. This fact alone shows us that genetics or DNA similarity is an inferior explanatory model when stacked against microorganisms and their impact. In theory, we are the descendants of the humans who made it, the mice are the descendants of the mice who made it, and our symbionts are the descendants of the microbes who made it. Since we all made it, there must be balances which work together, and on the opposite side, imbalances which work against each other. Everyone has to get along for everyone to get along. Some researchers believe that even parasitic infection has a BENEFICIAL role in the maturation of the human immune development (which, by the way, is likely why allergies are on rapid rise, but only in the parts of the world where we sterilize every surface all the time).
This former science fiction idea of mine is now a growing scientific reality. As such, I’ve had several clients get fecal microbiota transplants at international clinics (since the US is so unbelievably behind the curve). So far, the treatments cured anxiety and autoimmune disease without any accompanying drugs. However, this step is not just literally foreign to our archaic American medicine, it is metaphorically foreign to our archaic American minds. Until the large pharmaceutical interests can figure out how to make it ineffective and perpetually profitable (like they repeatedly do with all treatments), we won’t likely see an FMT clinic around the corner.
In the meantime, you can pay a little closer attention to fiber intake, aiming to gradually increase above the 30 gram mark. As you do, beneficial symbiotic relationships can be engendered. Some day, just maybe, even the extreme laggards like the Mayo Clinic will join modernity and recommend the same. At that point, we can hopefully stop bacteria from making us fat.