It's amazing how much of our digestive system isn't known.

Having had a bad flu years ago, it had a life altering impact on my own system, where I now have to be very particular about what I eat, because I lost so much of that good bacteria.

This in turn has an impact on my SO, since she eats mostly what I eat. My son has a bit more diet diversity, since I worry he'll end up in a similar condition.

My SO had a similar experience -- she had a bad flu a couple years ago and ever since has had a really rough time with certain foods. She's had tests for H. Pylori and all the other usual suspects (all negative). She's tried going gluten-free and FODMAP diet and hasn't been able to identify any consistent pattern.

A friend in similar circumstances had a lot of improvement from a poop transplant, might be worth a try.

Wow. Internet is beautiful. I never knew this was a thing.

I recommend trying cabbage juice, my fathers credits it as nearly curing his ulcers (unfortunately I don't know if his are caused by H. Pylori).

I wish her a lot of luck. It took me years to get things bearable. And there's a long way to go.

There's others, but garlic and onion are two of my triggers, and it's amazing how much food uses one or both.

I've also found that there's a sort of buildup effect with me. If I have certain foods two days in a row, or more than x times a week it can cause issues.

All that means it's quite hard to pin it down.

I stopped eating dairy for a few days and had a glass of milk with a severe reaction, used to drink a glass a night. Wonder if it is because all the bacteria that would process that lowered?

Perhaps a naive question but have you tried a good probiotic to rebuild your gut bacteria?

Probiotics take over your gut flora, probably best to talk to a good nutritionist or health practitioner to come up with a plan

Maybe try meat-only? Some people seem to have benefited from that.

I have heard promising things about fecal matter transplants for situations such as this, hopefully one of those procedures can heal you soon.

FWIW The evidence we have (not much I can find) seems to suggest that Native Americans today may not have very different biota. Maybe not surprising since their diets are more Western than not, now.

Biol Lett. 2014 Feb 12;10(2):20131037. doi: 10.1098/rsbl.2013.1037. Print 2014 Feb. Geographical variation of human gut microbial composition Taichi A Suzuki 1 , Michael Worobey

    PMID: 24522631 PMCID: PMC3949373 DOI: 10.1098/rsbl.2013.1037 

We found a positive correlation between Firmicutes and latitude and a negative correlation between Bacteroidetes and latitude. The overall pattern appears robust to sex, age and bacterial detection methods. Comparisons between African Americans and native Africans and between European Americans and native Europeans suggest no evidence of host genotype explaining the observed patterns.

https://pubmed.ncbi.nlm.nih.gov/24522631/

Gut Microbes. 2020;11(2):191-204. doi: 10.1080/19490976.2019.1634416. Epub 2019 Jul 16. Gut microbiota composition explains more variance in the host cardiometabolic risk than genetic ancestry Sandra J Guzmán-Castañeda et al

https://pubmed.ncbi.nlm.nih.gov/31311405/

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7053924/

The ethics scandal of paleofeces studies:

Because feces aren't considered human remains under U.S. law, Warinner says, there was little discussion early on about the ethics of the research. But when the group reached out to several dozen tribes in the Southwest, some said the samples were a link to their ancestors and were upset they hadn't been consulted earlier. The study now includes an ethics statement, a first for a paleofeces paper.

I don't understand what the scandal is?

I guess that the poop was owned in a sense

Really, who gives a shit?