Gut health is a complicated topic and the current science we have isn't very far in understanding it well.
The price for full gut flora sequencing is 159$ these days. If you have money to spend, actually measuring what going on with your gut flora and then measuring again after an intervention will make you less dependent on theory about interventions being right.
You have 100-200 species of bacteria which are together in a sort of Nash equilibrium. If you add new bacteria via oral probiotics, in many cases that won't change the Nash equilibrium and thus the effect of the oral probiotics is temporary. There will be other cases where the Nash equilibrium changes.
If you change your diet than there are different nutrients available in your gut that shifts the Nash equilibrium automatically for as long as the change in diet lasts. In some cases, you would go back to the same Nash equilibrium if you change your diet back to your old diet and in other cases a new Nash equilibrium will be found.
It makes some sense that a fecal transplant that adds 100-200 different species in a mix that's a working Nash equilibrium in a healthy person is more likely to help the patient to move to a new Nash equilibrium than adding three species of via a probiotic but it's still a process with a lot of moving parts.
That makes a lot of sense- this is definitely the sort of thing I was looking for, thanks so much!
I also read a concerning article by a professor that seemed to indicate that bacteria from probiotic foods doesn’t stick around in the intestine
Beneficial practices that have been around a long time accumulate simplistic explanations for why they work. I wouldn't lose interest in fermented foods just because this particular simplistic explanation has been refuted.
oral probiotics in general might just all be temporary.
The solution to concerns about it being temporary is to take them daily. I take Seed Daily Synbiotic. My gut is probably better as a result, but I don't have evidence that is at all rigorous.
Usually I do not recommend publications by outfits that sell products (e.g., Life Extension magazine is awful IMHO -- very mercenary) but I make an exception for publications by Microbiome Labs, like this next one:
One of my friends has been helped significantly by Microbiome Labs's protocols.
Is your friend still on the protocol?
What I'm really looking for is fixing the microbiome in a way which means I won't be having to take a pill to get the benefits forever.
Plant Chompers by Chris MacAskil has some good videos on this topic. The descriptions for these video have more links to other videos and articles on the same topic.
The Poop Whisperer: Dr Johan Van Den Bogaerde on Gut Health - Plant Chompers
I've been on a gut health kick, reading Brain Maker, adding more kale for the insoluble fiber, and cutting seed oils and sugar.
The author recommends probiotic enemas and fecal transplant, but I've seen mixed information on effectiveness of such treatments, and I also read a concerning article by a professor that seemed to indicate that bacteria from probiotic foods doesn't stick around in the intestine, which makes it seem like oral probiotics in general might just all be temporary.
Where can I find more detailed information about this? What can I do besides diet that actually works to improve your gut health/microbiota diversity?