Although the blog Mr. Heisenbug (“Respect the microbiota”) is quite new, I have learned a lot from it, especially about the importance of fiber. I interviewed the blogger:
HEISENBUG My name is Shant Mesrobian. My professional/academic background has no relation to the content of the blog. My background is in tech/politics/publishing. The blog is just a side hobby and is produced from independent research. (I’m a “non-expert” as you might call it.)
SETH When did you start your blog? What led you to start it? Have you blogged before?
HEISENBUG I started the blog about a month ago. I have not blogged before. I started it because the topic interests and excites me a lot. I anticipated a surge in microbiome experimentation and “hacking” and felt I could help direct that conversation in a productive direction. In digging through the research, there seemed to be a lot of dots that needed connecting.
SETH What do you mean, “dots that needed connecting”?
HEISENBUG Certain clusters of bacteria, and certain mechanisms (butyrate production, endotoxemia) kept surfacing in the studies I came across. For instance in the smoking post, it was sort of staring at you in the face that smoking clearly reduces levels of bacterial groups that are implicated in health and disease. Yet the study didn’t seem to find that interesting, so there was a gap that needed to be filled. But the pattern could only be detected by someone who reads a bunch of disparate studies. Same with the obesity/transplant study — many people are trying to help themselves because they vaguely know that potato starch can elevate butyrate (perhaps not even that much) — so here is a study showing directly that a different microbiota can achieve that, and it is particularly by elevating levels of bacteria that I had previously implicated as being prime starch degraders + butyrate producers. It’s been a series of eerie coincidences that has kept me posting material.
In general, I think there is a bit of an information gap about how to alter gut biota — there isn’t a real understanding of what “fiber” is.
SETH What do people fail to understand about fiber?
HEISENBUG First, that fiber is an overly broad and useless term. The only definition you can assign to the term is “a food that, when consumed, is not digested and is transported directly to the large intestine.” But what happens to the fiber when it gets there is completely dependent on what type of fiber it is. The type of fiber most people are familiar with is the mechanical kind that is just a bulking agent. Insoluble. No fermentation or microbial impact. Comes out the other end. The fibers we’re interested in are the bioactive type that are not only fermentable by gut bacteria, but preferentially fermented by good, commensal bacteria. But this isn’t what people think of when they hear “fiber.”
The other thing that’s not understood is that fiber can make a significant impact on the microbiome. People are just very primed by the germ theory aspect of bacteria — that they’re “bugs” you have to “catch.” So while people have begun to accept the idea that there are good bacteria that you want, the understanding is still very stuck in the “you have to eat the bacteria to get good bacteria.” I’m a big fan of fermented foods (making & eating), but I don’t believe it’s the primary way to tend to one’s microbiome.
SETH How have your ideas/beliefs about fiber changed over the years?
HEISENBUG I currently consume a paleo/ancestral type of diet. Before then, I regarded fiber as most people do: a necessary, functional component of food that you need in order to “stay regular”. I sought it out mostly from whole grain foods. I did not realize there were different types of fiber, or that they had anything to do with gut flora.
Then, when I went paleo, I adopted the general paleo attitude toward fiber: fiber comes from grains and grains are bad, that fiber is an unnecessary bandage that covers up for a bad diet, and that good digestive health can be had by simply eating nutritionally dense, non-toxic foods that people are evolved to eat. Fermented/probiotic food being a helpful addition.
Then I came to my current position once I learned more about the microbiome. What I’ve realized is that while paleo/ancestral eating goes a long way toward correcting the modern standard American diet, it still retains one common feature with it (at least in the way most people seem to practice it), which is that it focuses primarily on feeding the upper GI, while starving the lower GI (ie, your large intestinal microbiota).
And the ironic twist is that by dropping wheat, paleo may in fact have LESS fermentable fiber than the standard American diet. That’s because, while it contains mostly insoluble fiber, wheat does contain a small amount of fermentable fiber, which means that wheat constitutes the primary source of fermentable prebiotic fiber for the average American. So drop wheat, and you probably just lost your predominant source of fermentable fiber for your gut flora.
SETH The most interesting idea I’ve seen on your blog is that smoking is associated with heart disease (and other diseases) because it reduces microbial diversity. Because of this idea, I’ve become a lot more interested in fiber. Is this your idea? As you say, because smoking is such a big risk factor, it is a good place to start to understand heart disease (and other diseases). What are other explanations of why smoking is such a big risk factor?
HEISENBUG I’ve never seen anyone else make the connection between smoking -> microbial diversity -> heart disease. Smoking’s high (#1) correlation has always intrigued me, especially since there have never been solid explanations for it. Separately, I’ve been reading about endotoxemia-induced inflammation and its effect on chronic metabolic disease. So when I came upon this study, it was sort of a smoking gun.
As I said, the explanations for smoking being a big risk factor, if you really read them, aren’t saying anything. They are generalities. “Smoking contributes to heart disease because it contributes to atherosclerosis.” Well of course. Atherosclerosis IS heart disease. The question is how? Smoking raises LDL cholesterol. Ok, but how?
The inflammatory cascade that results from loss of microbial diversity, a bloom in “bad” bacteria, and a decrease in “good” bacteria, is an explanation for all of those.
SETH Could the importance of fiber explain that famous failed beta-carotene trial? There had been plenty of correlations between beta-carotene and better health. Yet in an experiment, people taking beta-carotene if anything did worse than the control group. Maybe beta-carotene consumption was a marker for fiber (e.g., people who ate more beta-carotene ate more carrots).
HEISENBUG If the epidemiology that inspired the trial was based on high carrot consumption, then I think that’s definitely a possibility — carrots are fairly high in pectin, a type of fiber with decent prebiotic activity. But since the trial subjects did even worse than placebo, I find another explanation convincing — that unusually high doses of beta-carotene, which is a precursor to vitamin A, blocks actual Vitamin A.
SETH Has your better understanding of fiber improved your own health?
HEISENBUG My health is already pretty good, and I think I’m probably too young for metabolic and chronic disease symptoms to make themselves evident, so I “unfortunately” can’t report on those types of markers. So for me this is all preventative at the moment. And I have yet to experiment with some more potent, high-dose prebiotic sources. I plan to soon. But I have noticed a significant improvement in sleep and a next-day feeling of well-being, relaxation, and clarity after a day when my fiber intake is higher and I consume yogurt cultured with lactobacillus and bifidobacteria, and I suspect it has something specifically to do with the bifidobacteria. That’s just a hypothesis now and something I’m currently exploring on the blog. Figuring out the ideal sourcing, combination, and amount of fiber is really still a work in progress as far as I’m concerned. There’s no real handbook, and people are just starting to figure all of this out. Lots of people experimenting with resistant starch (in the form of potato starch) are reporting dramatic stabilization in blood sugar and weight, digestive improvements, and greatly improved sleep. I’m hoping that a lot of personal experimentation and self reporting, combined with gut sequencing services like American Gut and uBiome, will get us closer to figuring it out.