Modern city dwellers have lost about half their gut microbes • Hacker News Board

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

#151

Post by AussieWog93 » Fri, Jul 01, 2022, 12:42 AM UTC

ssnistfajen wrote: post #149

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…

Lactase persistence is regulated by genetic mutations, not gut microbes. The negative symptoms of lactose intolerance is exactly due to lactose being able to reach the gut and making the microbes there flourish by digesting lactose, creating large quantities of gas and other metabolic byproducts that cause flatulence, diarrhea, etc. People don't spontaneously become lactose intolerant just because they stopped eating…

Holy shit, that is the most over-the-top, aggressive response to a guy being factually incorrect about yoghurt that I've ever read.

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

#152

Post by etiam » Fri, Jul 01, 2022, 12:45 AM UTC

msbarnett wrote: post #100

etiam wrote: post #95

Earlier quoted context omitted.

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 s…

That's interesting, and thank you for bringing it up.

What I was speculating about though, and what may be more relevant for the (Science) article, also includes things along the lines of a microbe manipulating the host gene expression to improve its living conditions. For instance a species that derives energy by fermenting glucose to lactate might under certain conditions have better benefit from that piece of metabolism if it can also make the host act as a sink for the product.

Again, not sure if that particular example is real or documented, but the idea has some consequences for the sort of adaptations and connections one might find.

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

#153

Post by flir » Fri, Jul 01, 2022, 12:54 AM UTC

hprotagonist wrote: post #111

starwind wrote: post #105

Earlier quoted context omitted.

You are correct. It's likely that the majority of humans have been lactose intolerant for human history. It's primarily people of Northern European descent that are not lactose intolerant, but lactose intolerance is very common outside of those groups

and west african; by two entirely separate mechanisms, which i’ve always found to be quite cool.

I wonder if there's any advantage to inheriting both mechanisms.

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

#154

Post by throwaway202022 » Fri, Jul 01, 2022, 1:01 AM UTC

tompccs wrote: post #122

I'd put microbiome research high up on my list of things which will turn out to be junk science in a few years. A lot of the actual numbers in this are pretty tenuous. Primates have 80 species of bacteria and city dwellers have 50? Wow, stop the presses. A few years ago the fashionable thing was colonic irrigation (see https://journals.lww.com/ajg/fulltext/2009/11000/clinical_ef... ). Now it just seems the pendulum h…

> We're looking for reasons why we feel sick all the time but the reality is beyond basic things like being too fat and too sedentary, we are healthier than ever, and many many people had wretched miserable lives of chronic pain before modernity. The expectation of health is a modern conceit and this research is just a reflection of the constant anxiety that there is something wrong with us all - a cultural hypochondria.

Aside from things like infectious diseases, we're not healthier than ever. We have better medicine than ever, but disease states that were once rarities have become commonplace in our modern world: https://en.wikipedia.org/wiki/Lifestyle_disease

By the way, these are diseases which cannot all be blamed on "being too fat and too sedentary", as even skinny people can develop type 2 diabetes. Unheard of centuries ago.

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

#155

Post by wizofaus » Fri, Jul 01, 2022, 1:07 AM UTC

throwaway202022 wrote: post #154

tompccs wrote: post #122

I'd put microbiome research high up on my list of things which will turn out to be junk science in a few years. A lot of the actual numbers in this are pretty tenuous. Primates have 80 species of bacteria and city dwellers have 50? Wow, stop the presses. A few years ago the fashionable thing was colonic irrigation (see https://journals.lww.com/ajg/fulltext/2009/11000/clinical_ef... ). Now it just seems the pendulum h…

> We're looking for reasons why we feel sick all the time but the reality is beyond basic things like being too fat and too sedentary, we are healthier than ever, and many many people had wretched miserable lives of chronic pain before modernity. The expectation of health is a modern conceit and this research is just a reflection of the constant anxiety that there is something wrong with us all - a cultural hypochond…

This is true, but lifestyle diseases are somewhat easier to avoid than infectious diseases (plus all the various other things that could easily kill you in your first decade or so in bygone eras). I'd almost say lifestyle diseases seem to be, to a large degree, a choice - maybe not directly, but as a society we accept that if we want to enjoy all the privileges of modern technology and food availability etc., then we pay for it with heart disease or diabetes or certain cancers etc.

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

#156

Post by badkitty99 » Fri, Jul 01, 2022, 1:11 AM UTC

TranquilMarmot wrote: post #123

subsubzero wrote: post #103

Lacking these gut microbes has been posited to lead to depression and effect mood by a few researchers: https://www.science.org/content/article/evidence-mounts-gut-...

The future of antidepressants is fecal transplants for healthy gut bacteria (not even kidding)

No post body was provided.

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

#157

Post by throwaway202022 » Fri, Jul 01, 2022, 1:15 AM UTC

wizofaus wrote: post #155

throwaway202022 wrote: post #154

Earlier quoted context omitted.

> We're looking for reasons why we feel sick all the time but the reality is beyond basic things like being too fat and too sedentary, we are healthier than ever, and many many people had wretched miserable lives of chronic pain before modernity. The expectation of health is a modern conceit and this research is just a reflection of the constant anxiety that there is something wrong with us all - a cultural hypochond…

This is true, but lifestyle diseases are somewhat easier to avoid than infectious diseases (plus all the various other things that could easily kill you in your first decade or so in bygone eras). I'd almost say lifestyle diseases seem to be, to a large degree, a choice - maybe not directly, but as a society we accept that if we want to enjoy all the privileges of modern technology and food availability etc., then we…

> I'd almost say lifestyle diseases seem to be, to a large degree, a choice - maybe not directly, but as a society we accept that if we want to enjoy all the privileges of modern technology and food availability etc., then we pay for it with heart disease or diabetes or certain cancers etc.

It's a choice for many, but I think it's not a fully informed one. If I'd known in my teens and early twenties what I know now, there is a zero percent chance I would have eaten and lived the way that I did. These things don't seem to hit people until the point that their personal health is affected, and sometimes not even then.

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

#158

Post by wizofaus » Fri, Jul 01, 2022, 1:20 AM UTC

throwaway202022 wrote: post #157

wizofaus wrote: post #155

Earlier quoted context omitted.

This is true, but lifestyle diseases are somewhat easier to avoid than infectious diseases (plus all the various other things that could easily kill you in your first decade or so in bygone eras). I'd almost say lifestyle diseases seem to be, to a large degree, a choice - maybe not directly, but as a society we accept that if we want to enjoy all the privileges of modern technology and food availability etc., then we…

> I'd almost say lifestyle diseases seem to be, to a large degree, a choice - maybe not directly, but as a society we accept that if we want to enjoy all the privileges of modern technology and food availability etc., then we pay for it with heart disease or diabetes or certain cancers etc. It's a choice for many, but I think it's not a fully informed one. If I'd known in my teens and early twenties what I know now,…

Seems to me the same way we treat environmental damage, though in that case most of the suffering will fall on our kids and grandkids. But even the choices young adults are making today aren't really compatible with having a decent planet to live on in 60 years or so, barring some technological miracles.

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

#159

Post by hackerlight » Fri, Jul 01, 2022, 1:21 AM UTC

steve_adams_86 wrote: post #62

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…

One tricky part with fermented foods is that the salty ones appear to increase rates of colon and stomach cancer as I recall. I read something years ago about how as the Japanese population adapted a more western diet, heaps of ailments came upon them as you’d expect, but their salt intake declined so dramatically that they stopped experiencing stroke and GI tract cancers nearly as much. I think you’d need to pin dow…

Salt tolerance varies a lot with blood pressure

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

#160

Post by hackerlight » Fri, Jul 01, 2022, 1:28 AM UTC

asdff wrote: post #51

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.

chobani claims six strains of yogurts, I used that as starter for my homemade yogurt batches since then. Otherwise I try and get my exposure in from the environment. I'm vaccinated so I don't bother with the mask unless there are hard rules. I will avoid overusing hand sanitizer. I take crowded public transit and otherwise walk around sidewalks and stores with a bunch of people vs private car and delivery of all my n…

Is that beneficial if it's a busy area? There's some pollution that I want to simply avoid, primarily car exhaust and fine particles like tire dust.