Phil, our natural colon flora are 100 to 1 anaerobic. Strictly anaerobic microbes among them, apparently.
Exactly, it's not the presence of any anaerobes or even obligate anaerobes that's the problem, it's apparently an imbalance tilted even farther than that--too far toward anaerobic dominance, as the evidence you presented suggests. Whether the imbalance is the cause of cancer, as some scientists have posited, or merely the result of oxygen-depleted pockets in a human host, or a mix of cause or exacerbant and effect, is unclear. My best guess would be a mix of all three, cause, exacerbant and effect, possibly mostly effect, because these bacteria are not normally a problem when in proper balance in healthy hosts.
In the research that you and I cited, overgrowths of the obligate and facultative anaerobic bacteria Firmicutes, Clostridium, Bacteroides vulgatus, Bacteroides stercoris, and Bacteroides fragilis were reported as correlated with certain risks. Here is some more I found:
B. fragilis group is the most commonly isolated bacteriodaceae in anaerobic infections especially those that originate from the gastrointestinal flora. http://en.wikipedia.org/wiki/Bacteroides_fragilis
Enterotoxigenic Bacteroides fragilis (ETBF)-mediated colitis in Min (Apc+/−) mice
A human commensal-based murine model of colon carcinogenesis
They have different species in healthy vs. diseased, but they are usually anaerobes. Bifidobacterium are obligate anaerobes which are healthy in human gut flora according to some studies of colon cancer.
Right, and you indicated that Bacteroides, another obligate anaerobe normally in the gut of meat eaters, is associated with increased risk of colon cancer.
FYI just to clarify--bifidobacterium are aerotolerant
obligate anaerobes (see Development of the gastrointestinal tract, Volume 1, By Ian R. Sanderson, W. Allan Walker). It's an important distinction because super baddies like Clostridium botulinum and Clostridium tetani are not aerotolerant.
So given that obligate anaerobes are normally in the guts of healthy people but some of them are also associated with higher risks of cancer and other problems, it appears that gut health is about flora balance. Your sources suggest what may happen when the balance is disrupted. Perhaps what was once benign or even beneficial can become destructive when unrestrained?
Much about that in some of these links. While I think there is tremendous benefit in eating aerobic ferments like natto, moldy cheese and the like which make vitamin k2 and other vitamins among other things, the environment in the colon is anaerobic.
Maybe not completely anaerobic, as it is a hollow tube that sometimes opens at both ends? Where the completely anaerobic conditions appear to occur is when the mucosal barrier is broken and the anaerobes gain access to human cells and when the anaerobes can coat themselves in protective layers, sealing off the oxygen, allowing them to go about their dirty work of growth, further penetration, and destruction.
It just isn't exposed to much oxygen any way you look at it.
Sure, and in a healthy human perhaps there is just enough oxygen, competing bacteria and immune system soldiers to keep the anaerobes in check?
The aerobe microbes probably won't survive there (but some obviously do.) That is why eating the lacto-fermented foods can make a beneficial difference.
Yes, that's what I said I suspect--they may help to keep the more truly obligate anaerobes in check by competing with them. I don't understand why one would focus only on the lactobacilli and ignore or downplay the role of the others, especially in nondairy meat eaters like the Inuit, who as I think you pointed out, didn't have as much access to lactobacilli-rich foods. For meat eaters like the Inuit, "zero carbers," and some dirty carnivores who are not into sauerkraut, raw fermented honey or dairy products, the fermented meats, fish and sea oils seem to be especially important. It might be even better to include both types of probiotic foods in the diet. Many people know about lacto-ferments like sauerkraut and yogurt, but few know about non-lacto meat and seafood ferments.
Lex Rooker has hypothesized that animal-sourced bacteria from his intake of raw and mildly fermented meats may be part of the reason for his avoidance of the problems that cooked-meat zero carbers and VLCers have run into after a certain point, such as Mel's folic acid deficiency and Danny Roddy's very similar symptoms. This could be a crucial piece of the puzzle that some are missing, in part because of the wall of American social taboo, in which cracks have recently begun to form.
So if we can encourage the growth of the good, it is worth it. And that's what natives did. They ate both lacto and aerobic ferments of various sorts.
Exactly, and that is my point. As far as I can see, none of the people who failed on zero carb or VLC were consuming plenty of either.
And we see Anderson and Stef killing off between 15-50% of their gut flora eating meat and no ferments, and changing the types of species present over time. Their gut flora went back to normal after resuming a mixed diet. So I am inclined to follow native wisdom here. More ferments. Anaerobic, acid loving ferments of the right sort. And more wine too.
And all I'm doing is adding the aerobic ferments, not subtracting anything. As you know, I consume raw fermented honey and sauerkraut myself. I think it may be improving my tolerance a bit for certain carby foods.
Thanks for more links. I am learning a ton right now and am so glad I have elicited the mad scientist in you. Pretty fascinating about honey producing H2O2. I was aware of its use in wound care, but not the reason why it might be helpful.
You're welcome, there are other posited reasons too, such as the beneficial microbes in raw and raw fermented honey and the natural plant antibiotics that the bees obtain from plant nectar, especially from wild plants that haven't been weakened by domestication. I'd love to try wild
raw fermented honey some day, particularly a good tasting one. Presumably it would be the most beneficial of all types of honeys.