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Modern city dwellers have lost about half their gut microbes

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Re: Modern city dwellers have lost about half their gut microbes

#81
post #45

Pretty much every culture around the world 100 years ago had some staple fermented food. Nowadays, a lot of people in western culture at least outright refuse yogurt or other fermented foods like saurkraut or pickled cabbage that used to be staples in these people's ancestor's diets a few generations ago. People are becoming even lactose intolerant. You have to fertilize your microbes so to speak and eat these sorts…

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Re: Modern city dwellers have lost about half their gut microbes

#82
post #45

Pretty much every culture around the world 100 years ago had some staple fermented food. Nowadays, a lot of people in western culture at least outright refuse yogurt or other fermented foods like saurkraut or pickled cabbage that used to be staples in these people's ancestor's diets a few generations ago. People are becoming even lactose intolerant. You have to fertilize your microbes so to speak and eat these sorts…

Eating yogurt or sauerkraut will not render you (once again) lactose tolerant.

Lactase (the enzyme that breaks down lactose) production is regulated by a human gene; how would a probiotic like yogurt alter a gene?

https://biologydictionary.net/lactase/

Re: Modern city dwellers have lost about half their gut microbes

#83

It's the iron fortified flour and then the people are like OMG I have celiac and what not. There's a reason breast milk and milk in general contains lactoferrin; guess what, they also remove it from most milk that is in supermarkets.

The burden of proof for a coeliac disease diagnosis is quite high: a biopsy from an endoscopy that shows classic signs of damaged villi (from autoimmune mechanisms), or a blood test with extremely high tTG levels and a family history of the disease.

https://www.bsg.org.uk/covid-19-advice/covid-19-specific-non...

Re: Modern city dwellers have lost about half their gut microbes

#84

Earlier quoted context omitted.

How does one analyze the gut biome? I imagine it involves running poop through a machine - what kind of machine? I would love to learn more about the technical process.

The paper uses 16S rDNA sequencing, which is a bit old fashioned now but it was a good method when the paper was published. The steps basically involve: 1. Extract all DNA from poop, normally using a kit that basically makes DNA stick to tiny plastic beads. You wash the beads in a bunch of different chemical solutions to isolate DNA from the original sample and purify it. There are a lot of different methods to do th…

Great summary! Although I would argue that 16S is still a perfectly good (and cost-effective) method, especially with DADA2. There are also neat sequencing techniques that like CCS which give you really high resolution of a target region (amplicon) without sequencing a lot of redundant/uninformative DNA.

Re: Modern city dwellers have lost about half their gut microbes

#85
post #45

Pretty much every culture around the world 100 years ago had some staple fermented food. Nowadays, a lot of people in western culture at least outright refuse yogurt or other fermented foods like saurkraut or pickled cabbage that used to be staples in these people's ancestor's diets a few generations ago. People are becoming even lactose intolerant. You have to fertilize your microbes so to speak and eat these sorts…

Eating yogurt or sauerkraut will not render you (once again) lactose tolerant. Lactase (the enzyme that breaks down lactose) production is regulated by a human gene; how would a probiotic like yogurt alter a gene? https://biologydictionary.net/lactase/

You could always ingest other bacteria that can digest and break down lactose and rely on probiotics to digest the lactose for you instead of having a gene.

That's what ruminents do anyways, you need a steady colony of these helpful bacteria or you lose the tolerance. While that seems troublesome, for many animals that's how metabolism works for their entire life.

Re: Modern city dwellers have lost about half their gut microbes

#86
post #5

>people in U.S. cities...people in less developed parts of the world What about people in the US who are not in cities? That's the more interesting comparison to me. Why would that be left out?

> What about people in the US who are not in cities? That's the more interesting comparison to me. Why would that be left out? At least in the US, my lay-intuition is that you wouldn't see much of a difference between average Americans between urban, suburban, and rural settings. That's perhaps worth testing, but I think the much more interesting test would be between wealth and class groups. (Again, wild speculation…

> but definitely do care about $14 free-range, organic eggs

Can you elaborate on why you think this is the case? Intuitively to me, most folks’ diets are going to be mostly cooked eggs which would reduce any effect on bacteria in the gut.

Re: Modern city dwellers have lost about half their gut microbes

#88
post #45

Pretty much every culture around the world 100 years ago had some staple fermented food. Nowadays, a lot of people in western culture at least outright refuse yogurt or other fermented foods like saurkraut or pickled cabbage that used to be staples in these people's ancestor's diets a few generations ago. People are becoming even lactose intolerant. You have to fertilize your microbes so to speak and eat these sorts…

Eating yogurt or sauerkraut will not render you (once again) lactose tolerant. Lactase (the enzyme that breaks down lactose) production is regulated by a human gene; how would a probiotic like yogurt alter a gene? https://biologydictionary.net/lactase/

Epigenetic reversal of some inhibitory histone marks at the promoter region of the enzyme? Driven by some yet-to-be-discovered signaling cascade induced by reintroduction of lactose and proliferation of lactose loving microbes?

Just spitballing, this is pure speculation, but is plausible.

Re: Modern city dwellers have lost about half their gut microbes

#89

It's the diet. City dwellers tend to eat a lot more unhealthy foods. They also eat a lot less vegetables, fruit and nuts than their rural country(wo)men. You want more microbes in your gut? Eat more plant-based food.

Based on the way my body responds and reviewing lab results after trying different diets, I am of the opinion that it has more to do with processed foods versus minimally/unprocessed foods. I don’t think whether it is plant or meat/dairy based really matters that much nutritionally. Enriched flour, is plant based but by no means do I believe that to be healthy. Same goes for sausage and bacon, too processed. N of 1 but since I stopped consuming processed food and stopped worrying about cholesterol while restricting calories, eating plenty of fruit & veggies, and exercising, I have actually lowered my ldl cholesterol by 40 points. Triglycerides were fine. Dr was thrilled, didn’t have the heart to tell her I didn’t follow her advice.

Re: Modern city dwellers have lost about half their gut microbes

#90
post #49

It's the diet. City dwellers tend to eat a lot more unhealthy foods. They also eat a lot less vegetables, fruit and nuts than their rural country(wo)men. You want more microbes in your gut? Eat more plant-based food.

Having lived both in the city and fairly rural, I can say that access to a healthy and varied diet is much much easier in the city. Both when it came to restaurants and buying and cooking food.

Small town / suburban areas can be the best with large supermarkets or dedicated markets, as long as you have a car.

That said bushland in Australia has natives that you can’t buy in the supermarket. So there is that.

But the average person probably doesn’t forage.

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