Buzz is out that Dave Asprey didn't like his RS via PS experiment. (I would have been surprised if he had, because if beneficial, LC is an ass and he's been wrong for a long time—which I love to be, but he's not demonstrated, yet.) Moreover, if he actually took the months I and others have taken to be able to down bolus doses of PS, chased with beans and have no bloating or gas, then it would necessarily mean that he or his protocols are not all that "Bulletproof."...If he couldn't manage to go where so many other men and women have managed to go, in the hundreds, worldwide? Bulletproof?
Or, does Bulletproof mean Tender Flower, at the end of the day?
The irrational assumption is that when everything doesn't come up roses, that there's something wrong in eating a natural, easily obtainable fraction of a potato that doesn't even get digested by you (hunter-gatherers can make potato starch). From what I got 2nd hand from the podcast, Dave is concerned with feeding bad bacteria. But I thought we're in a Bulletproof context? Bad bacteria? Enough to make a difference, and with all that daily intake of butyrate and MCTs?
PS feeds a variety of bacteria, and some feed only off the by-products of others that eat RS. The general idea is that with 100 trillion gut bugs, you're pissing up a rope tied to a string you're pushing upwind to try to figure this out. You need to trust evolution.
So, most simply, the idea is that resistant starch is a very proven substrate that feeds good bacteria and some bad. It's they who are your antibiotic chemical plants against each other. And guess what? This war is 3 billion years old, so evolution probably has something to do with why the normal human state is for lots of good bugs, with bad ones who piss in the pool, kept in check. They can evolve antibiotics that work far faster than all the drug companies and FDA combined, and are species targeted. Of course, this is evolution we're working with, and not even the good guys care about a human life; so man-made antibiotics definitely have their place. I'll take a fucked up gut any day if I get to live another day, should I have a raging infection and the good guys have been overcome.
...But please understand: I like Dave, and quite a lot. He cracks me up, and I've sat across the table a couple of times (who puts a pat of butter on his sushi? Dave, that's who.). He knows this—si il n'existait pas il faudrait l'inventer—and I'm just a different sort of self experimenter, not to mention a different kind of blogger and promoter.
...A commenter, DuckDodgers, took the time to embed a bunch of links in text for a comment, and I figured that nice work needed a bigger audience. It began with something someone else had written.
Besides it’s not as if gut bacteria is optional – you need to have it anyway, thus feed it anyway, it’s just a decision how much food they get.
Here's why Asprey's fear mongering is weak. Just look at the evidence (hat tip to Jeff Leach, of the American Gut Project).
Jeff Leach wrote: When it comes to the health and well being of your gut microbes, nothing matters more than fermentable substrates (You can read about here, here, here, here, here, here, here, here, here – you get the idea). As the rules/tenants of basic microbial ecology go, a reduction in fermentable substrates derived from carbohydrates means less energy sources for the microbes – who depend on host-derived substrates as well, as in the case of mucin-degraders like Akkermansia. As fermentation drops, so to does the byproducts of fermentation which include short chain fatty acids (primarily acetate, butyrate, propionate), organic acids, and gases like hydrogen. All of this can and will dramatically shift the pH of the colonic environment. As it stands in a healthy or normal gut, the pH of the colon changes from proximal to distal end, being more acidic in the proximal (front) end than the tail end – mainly as a function of more rapid fermentation as food items empty from the small intestine. As the pH shifts to being more alkaline from less fermentation, a number of shoes begin to drop (or can). A less acidic environment means acid sensitive groups of bacteria, like those in the Phylum Proteobacteria, which includes a who’s who of bad guys like strains of E. Coli, Salmonella, Vibrio, Helicobacter, might bloom – not a good thing. You see the same blooms following antibiotic treatment. In addition, as pH shifts away from acidic, the genus Bacteroides can also bloom as well, gaining an ecological niche in this less acidic environment courtesy of a low carb diet. For those of you keeping score, many talk about the American gut in general being dominated by Bacteroides as a function of our high fat, high sugar diet. The reality is, it might have to do with what we are not eating – dietary fiber (of all kinds). The all-important butyrate producers Roseburia spp. and Eubacterium also drop in abundance as pH shifts away from acidic as well. A drop in fecal butyrate and butyrate producing bacteria was demonstrated in an elegant study comparing diets of varying amounts of carbs. Given the importance of butyrate in colonic health, any dietary strategy that potentially shifts pH away from acidity as a function of reduced fermentation, might contribute to various forms of IBD. So, low carb equals a less acidic colonic environment due to the drop in fermentation (and I presume harder, and less frequent stools as a function of reduced biomass from bacteria – or maybe not). As pH shifts, prospects for opportunistic pathogens increase, as does opportunities for gram-negative bacteria like Bacteroides and Enterobacter. When you add this up – and a lot of more shifts in the microbial ecology of the low carb gut – you most certainly have a classic case of microbial dysbiosis – as the name implies, an imbalance. This dysbiosis can lead to issues associated with IBD, autoimmune disease, metabolic disorders and so on. But again, a large cohort of low, low carb dieters has never been looked at using 16S rRNA methods. So the jury is still out – but will be fascinating to see. [end quoted text]
Click on those studies that Leach references — particularly the ones about pathogens disappearing when the pH shifts from alkaline from to acidic.
Now, consider that pathogens, like Candida, become benign in acidic environments and pathogenic in alkaline environments, and you begin to see the big picture.
People who worry about RS feeding the bad microbes seem to be oblivious to the fact that it very likely doesn't matter since the "good guys" bloom in an acidic digestive tract and the bad guys get crowded out and inactivated by those same acids.
Ball. Court. Dave.