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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

#241

Post by somenameforme »

moreira wrote: post #222
somenameforme wrote: post #219

I'm curious how simple sanitary factors come into play. Something I've always found intriguing is that in Ancient Greece toilets would use shared butt brushes (sponge on a stick) in lieu of toilet paper. In an especially fancy place there might be a bucket of vinegar nearby to clean it off, but in general it was just a quick swirl through some water and onto the next bum. The thing I find interesting there is that th…

It seems like it’s about statistics, more than anything. Some people can be sedentary and smoke their whole lives and eat lard non stop and still live to be 80. Doesn’t mean any of that helped them in any way. It’s like that for them, too; regardless of their sanitary practices, some people will live to be old. On its own I don’t think it says much about their effectiveness. Long-lived people have always existed. The…

That's exactly what I was hitting on. Ancient Greeks living to quite old age were not statistical outliers, but the norm! The only way to explain this with contemporary understanding is to suggest it's just an extremely large survivorship bias, but that seems to difficult to swallow because many of those we know of from Ancient Greece we would likely still know of even had they died decades earlier as well.

This [1] study looked at the mean age of Greeks "of renown" from the 5th and 4th century and found the average life expectancy was 71.3 years! There's certainly a class bias, but when we're speaking of times of antiquity all the money it world couldn't buy you what didn't exist. So all that bias would represent is, at best, more or less secure access to food, drink, and other basic necessities.

[1] - https://pubmed.ncbi.nlm.nih.gov/18359748/

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

#242

Post by ls15 »

ssnistfajen wrote: post #226
ls15 wrote: post #209

Earlier quoted context omitted.

> Lactase persistence is regulated by genetic mutations, not gut microbes. > Koreans eat lots of fermented vegetables, yet why are 70%-100% of Koreans estimated to be lactose intolerant? On the other hand, there is Mongolia: > But a closer look at cultural practices around the world has challenged that picture. In modern Mongolia, for example, traditional herders get more than a third of their calories from dairy pro…

So how exactly does the diet of Mongolians prove lactase persistence is not fundamentally genetic? Lactose intolerance isn't something like celiacs where a dash of the substance causes adverse reactions. Most of Asia still sell non-lactose-free dairy in supermarkets. Look up any Youtube video of Korean street foods and you will see dairy products such as processed cheese, yogurt, mil, and ice cream are ubiquitous in…

> So how exactly does the diet of Mongolians prove lactase persistence is not fundamentally genetic?

It doesn't, but I think it indicates that genetic lactase persistence is not the only factor that affects lactose intolerance. Otherwise, how do you call a lactose-intolerant person that can tolerate significant amounts of lactose?

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

#244

Post by kewrkewm53 »

I wonder how much of the fast increasing prevalence of gut-related diseases like IBS can be explained by the changes in gut microbes, and how much is just about lack of exercise and changes in diet.

Whenever I go work at relative's farm my stomach seems to work way better, even though I do plenty of exercise in my home city as well. Perhaps the type of manual labor is better for stomach than gym/running, but I wouldn't rule out the impact of microbes either.

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

#245

Post by 867-5309 »

culi wrote: post #198
makeitdouble wrote: post #180

Earlier quoted context omitted.

> indicating the importance of preserving this treasure of microbial diversity from ancient rural communities worldwide This study (and the FA) mention losing/presrving microbial diversity, but don't touch on how we got these microbes in the first place. I was expecting it comes mostly from what we eat and the environment, including eventually the people around us (and the mother - baby link ?) I kinda wondered if we…

Very likely. Almost all probiotics people take are transient. Meaning they just pass through and don't form long term colonies in our guts. There's a few exceptions with some soil-derived probiotics but those are also the least predictable It seems really likely to me that our bodies have likely adapted to an environment where exposure to certain types of bacteria is very common. For example, there's been a lot of re…

>Almost all probiotics people take are transient. Meaning they just pass through and don't form long term colonies in our guts.

is this also the case for frequent ingestion? say you eat probiotic yoghurt on a regular basis, are you saying the good stuff is in a constant cycle of dying and being replaced?

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

#246

Post by deepstack »

moistly wrote: post #187
K0SM0S wrote: post #121

Earlier quoted context omitted.

Gut biome being one of the most promising area of research, whose earth-shattering potential is about on par with the sheer complexity of the problem. If you thought ML was difficult, try modeling a human being's digestive tube from mouth to anus down to the cell: welcome to a category of problems where climate and gravity are the "simple" ones. On the other side of that space though, potentially the promise to incre…

We are a symbiote.

Bingo, we are just bunch of bacteria walking around. Some organism become symbiotic over time like mitochondria, so it go incorporated into our cells to make energy. The whole concept that we as human-being is one organism needs to be revisited.

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

#247

Post by rvba »

ebolyen wrote: post #84
nebfield wrote: post #72

Earlier quoted context omitted.

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.

How big are the samples analyzed by the machine? 1 gram? 1 miligram? Are they taken from random parts of the poop? (Outside, inside?)

Even 1 miligram is probably a lot of DNA, but I wonder how to know if the place of sampling is important

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

#248

Post by GistNoesis »

Spinosaurus wrote: post #181
kaycebasques wrote: post #66

I had to use oral antibiotics about a year ago for reasons that could have been avoided. I was pretty upset about it precisely because it probably wreaked havoc on all the beneficial gut microbes that I had built up over the years.

Have you had any lasting effects? I've been prescribed a "fairly serious" antibiotic for a skin condition that has been plaguing me for several years (I've gotten like 5 different diagnosis and tons of different Rx). I'm otherwise incredibly healthy, so this antibiotic scares the shit out of me and I have yet to start taking it.

Have you tried cleaning your washing machine regularly ? People often think of washing their pillow cases and sheets once a week, but if the washing machine isn't well maintained, the bacteria don't get properly killed and you spend all nights and day with them, and no amount of skin-cleaning and hydrating products will be able to work.

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

#249

Post by collyw »

culi wrote: post #198
makeitdouble wrote: post #180

Earlier quoted context omitted.

> indicating the importance of preserving this treasure of microbial diversity from ancient rural communities worldwide This study (and the FA) mention losing/presrving microbial diversity, but don't touch on how we got these microbes in the first place. I was expecting it comes mostly from what we eat and the environment, including eventually the people around us (and the mother - baby link ?) I kinda wondered if we…

Very likely. Almost all probiotics people take are transient. Meaning they just pass through and don't form long term colonies in our guts. There's a few exceptions with some soil-derived probiotics but those are also the least predictable It seems really likely to me that our bodies have likely adapted to an environment where exposure to certain types of bacteria is very common. For example, there's been a lot of re…

> Besides keeping us less stinky by eating our sweat That sounds wrong. Sweat itself doesn't smell until microbes have had a chance to act on it. You can sweat right after a hot shower and you won't smell.

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

#250

Post by collyw »

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…

Even the fermented food that you mention will not be probiotic if they are commercially bought. Sauerkraut in a jar will be pasteurized. Even probiotic yogurt is supposedly pasteurized then some live culture added after. I make my own kefir and saurkraut for that reason.
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