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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

#91

Post by msbarnett »

asdff wrote: 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…

> People are becoming even lactose intolerant.

This isn't new, and certainly isn't some crisis of the last 100 years. Historically only a minority of the planet has ever been lactase persistent into adulthood. It's a well-understood genetic trait, not some product of gut microbes.

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

#92

Post by cheese_goddess »

rr888 wrote: post #20

Does anyone know of probiotics with a variety of bacteria? Currently they (and yoghurts) seem to be just a single type, which doesn't make a lot of sense to me. If there are unusual bacteria out there where do they come from and how can we get them? I've done a bunch of anti-biotics in the last few years so what to get back to what I was.

If you want variety of bacteria, then the highest is probably in milk kefir, and the second highest in aged, hard cheese.

Kefir, we don't even know how many or what bacteria it hosts, but we know it's a lot. Different studies have reported wildly different communities, but all of them with upwards of a dozen species. For example:

> Sequencing-Based Analysis of the Bacterial and Fungal Composition of Kefir Grains and Milks from Multiple Sources

https://journals.plos.org/plosone/article?id=10.1371/journal...

Aged hard cheese, unless made with raw milk, is usually inocculated with a couple of strains of lactic acid bacteria, but during aging a varied flora develops, of "adventitious bacteria" and yeasts from the environment.

To be honest though, I made kefir for a couple of years and I've been making cheese for about four now and I make the occasional yogurt now and then, but I'm still not convinced about the health claims of "probiotics". And I'm not the only one to be skeptical:

> A growing probiotics market has led to the need for stricter requirements for scientific substantiation of putative benefits conferred by microorganisms claimed to be probiotic.[7] Although numerous claimed benefits are marketed towards using consumer probiotic products, such as reducing gastrointestinal discomfort, improving immune health,[8] relieving constipation, or avoiding the common cold, such claims are not supported by scientific evidence,[7][9][10] and are prohibited as deceptive advertising in the United States by the Federal Trade Commission.[11] As of 2019, numerous applications for approval of health claims by European manufacturers of probiotic dietary supplements have been rejected by the European Food Safety Authority for insufficient evidence of beneficial mechanism or efficacy.[8][12]

https://en.wikipedia.org/wiki/Probiotic

Btw, you know what elese has plenty of lactic acid bacteria, therefore probiotics? Sourdough. Alhtough if you make kefir, you can use it instead of sourdough as a bread starter.

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

#93

Post by woodruffw »

mathgeek wrote: post #86
woodruffw wrote: post #69

Earlier quoted context omitted.

> 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.

Sorry, I meant that as a proxy for “families that have the purchasing power to buy premium goods.” My intuition is that there’s a weak inverse relationship between food processing and food price, with less processing corresponding to healthier gut biota. But you’re right that the $14 eggs themselves probably don’t matter.

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

#94

Post by dannyperson »

zdragnar wrote: post #18
haklport wrote: post #8

"Moeller and others also suggest identifying the missing microbes may be the first step toward bringing them back. “If we determine that these groups were providing important functions to keep humans healthy,” Maccaro says, “perhaps we can restore them with probiotics.” Oh really? Nice submarine for Actimel, Yakult etc.

Well, it's either a pill, or moving out of the city, or a fecal transplant (assuming that the urban / rural divide is relevant, and not just a proxy for diet). I don't live in the city, but if I were told that I would be healthier with more of these microbes that my environment doesn't support, I'd opt for the pill.

The study compares humans (who happen to live in cities) to primates (who definitely don't live in cities). It doesn't compare between human populations.

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

#95

Post by etiam »

giardini wrote: post #82
asdff wrote: 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/

Well, as you probably know, genes are regulated more or less according to environmental cues all the time, including being very much subject to presence and behavior of commensals/parasites/symbionts.

I don't know any specific data whatsoever about inducing lactase, but it seems perfectly plausible that microorganisms such as lactic acid bacteria could interact with the system.

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

#96

Post by fosk »

wheelerof4te wrote: post #71
lnxg33k1 wrote: post #59

Earlier quoted context omitted.

Well of course it’s obvious that we’re not carnivorous our ancestors didn’t eat meat and always used to go to the pharmacy to get their iron and B vitamin supplements

Plenty of both iron and vitamin B in plant-based food. You really believe we hunted big game so much? With what? Sticks and stones? How did we catch them with our weak legs? How the hell did we skin them or eat their raw flesh? Cooking wasn't a thing for a long time. And why don't we eat the animal meat raw? Don't you love it when you see the dead, rotting carcas all open and blody? I sure don't. And neither would yo…

Humans used to exhaust their prey. Once the prey is exhausted - in the absence of better tools - pick a rock and hit the head of the animal until it dies.

There are videos of animals (like deers) so exhausted they just sit there while a lion eats them alive: they are not moving, they are not standing up, they are just sitting there watching another animal eating their guts alive. Just like that.

You can eat meat raw as long as it’s fresh (just killed), likewise we eat raw fish as long as it’s fresh. Carpaccio is raw meat, for example, and very popular too.

We were eating less meat - for sure - since cutting and digesting raw meat takes longer. But I guess we were also eating less of everything to begin with.

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

#97

Post by lnxg33k1 »

wheelerof4te wrote: post #80
lnxg33k1 wrote: post #74

Earlier quoted context omitted.

I don’t know I meet a lot of people that say that there is a lot of iron and B in plants but all the vegan I met working were always taking supplements, maybe if you tell me what are the plants with B12 and iron I can pass over the info next time I see one of them

There is abundance of iron in spinach, nettle and other similar plants. For the b12 needs, eat some algae or even dirt. Yes, dirt. Plenty of dirt on a plant's root, which ancient humans ate like no tomorrow.

Eating dirt seems much more natural than eating animals, I guess they discovered the fire to cook the dirt then, i guess tonight I found the reason why vegans are full of shit :D

Ps just searched for ‘dirt b12’ on ddg and the first website is an ad for b12 supplements

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

#98

Post by msbarnett »

amarshall wrote: post #57
asdff wrote: 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…

> You have to fertilize your microbes so to speak and eat these sorts of foods [citation needed]. It seems unlikely that fermented foods are not consumed in urban areas at all. I’ve also no idea if other primates consume any fermented foods, but I’d guess probably not. > People are becoming even lactose intolerant Do any other primates drink milk after infancy? If not, that’s not really a valid concern in the context…

No. In fact, almost all mammals stop producing lactase once they stop nursing from a mother. Humans are quite rare in that there's a significant population with the mutant "lactose tolerant adult" gene.

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

#99

Post by dannyw »

msbarnett wrote: post #91
asdff wrote: 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…

> People are becoming even lactose intolerant. This isn't new, and certainly isn't some crisis of the last 100 years. Historically only a minority of the planet has ever been lactase persistent into adulthood. It's a well-understood genetic trait, not some product of gut microbes.

You can think of this being evolutionary beneficial, if some milk is bad, the whole village don't all get sick.

Also a possible reason for why people have different taste preferences.

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

#100

Post by msbarnett »

etiam wrote: post #95
giardini wrote: post #82

Earlier quoted context omitted.

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/

Well, as you probably know, genes are regulated more or less according to environmental cues all the time, including being very much subject to presence and behavior of commensals/parasites/symbionts. I don't know any specific data whatsoever about inducing lactase, but it seems perfectly plausible that microorganisms such as lactic acid bacteria could interact with the system.

This has been studied, but the results tend to argue that it's purely genetic, eg)

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6669050/

> Studies that have measured changes in endogenous lactase activity after an intervention period consistently show a lack of enzyme induction, suggesting that lactose intake does not affect an individual's lactase activity. Although these studies are scarce and have relatively few subjects, data from cross-sectional studies support the theory of purely genetic regulation

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