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Modern city dwellers have lost about half their gut microbes

science.org

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

#141

Post by steve_adams_86 »

lemming wrote: post #137
steve_adams_86 wrote: post #108

Earlier quoted context omitted.

Interesting, thanks for that. I hadn’t seen it yet. Though the rest still stands, and as mentioned in the paper, reducing sodium intake is still recommended for other health benefits. There is a wealth of other research showing that most people in North America should dramatically reduce their sodium intake. > Reduction of processed meat intake may be an effective strategy for CRC prevention, while sodium reduction s…

There is a wealth of other research showing that most people in North America should dramatically reduce their sodium intake. The evidence for this seems much less conclusive than most people think: https://examine.com/nutrition/awful-nutrition-myths/#summary... . The tl;dr is that most of that salt comes from crappy food, and that’s what you want to fix - it’s not the salt as such.

It really is the salt though, and examine says as much:

> Some myths contain a grain of truth. Studies have associated excess salt with hypertension (high blood pressure),[54] kidney damage,[55] and an increased risk of cognitive decline.[56][5

The thing is, a lot of people have no idea that their salt intake is way too high. You’re right that the salt tends to come from processed foods, but the salt is still a problem.

I’m not trying to suggest the processed foods are not a problem, either. It’s a compounding problem, and it’s a massive one.

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

#142

Post by hypertele-Xii »

msbarnett wrote: post #102
dannyw wrote: post #99

Earlier quoted context omitted.

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.

It's probably simpler than that: it's simply not energy-efficient to keep producing an enzyme throughout its life for a sugar that's rare-to-non-existent in an organism's diet for most of that life. Because mammals don't have any means of obtaining milk once they separate from their mother, lactose intolerance for their lifetime after weaning is almost universal among mammals. Over millions of years, the slight energ…

The specific enzyme that breaks lactose is lactase. It's built from almost 2000 amino acids. In comparison, Alpha-Amylase, the enzyme that breaks starch, is much smaller. Couldn't find an exact count but it appears in the ballpark of 200.

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

#143

Post by astrange »

starwind wrote: post #109
digitcatphd wrote: post #87

I think the consensus is nobody really knows and nutritional science is largely trendy pseudoscience…

I've always been shocked at how crappy the research into nutrition is and how there's very little consensus beyond "vegetables are good" and how shoddy a lot of the professional training is for dieticians. Nearly everybody eats nearly every day, how have we not figured this out?

It's both difficult and largely unethical to do intervention studies on people, and we don't know how to measure individual differences between people very well.

For instance, studying gut biomes of people is mainly done by looking at their poop but that doesn't help you know what kind of bacteria are where in their intestines, and it's not like you can take them apart.

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

#144

Post by astrange »

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.

Most probiotics aren't useful because if you're going to manufacture a ton of bacteria, you have to go with the ones capable of growing that fast. That's typically just one or two strains used in the making of yogurt, though you could branch out to miso, kefir, kimchi etc.

And the oral delivery route doesn't work that well because they have to make it through the stomach, then get to the intestines, then survive there - which they won't if they aren't specific strains evolved to live inside humans.

If you want to do science (aka mail someone your poop) there are ways to measure what's currently inside you:

https://www.viome.com

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

#146

Post by astrange »

hahaxdxd123 wrote: post #55
wheelerof4te wrote: post #41

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.

> near non-sequitur thesis not discussed in article stated definitively > flimsy evidence which isn't true [ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3365871/ ] Certified HackerNews moment!

"Cities are unnatural therefore they contain less natural foods" is the West Coast/boomer environmentalism mindset, so this is actually a California moment.

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

#147

Post by wtetzner »

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.

Kinda feels like identifying the missing microbes should instead help us track down what we’re doing that’s causing them to die off.

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

#148

Post by lovehashbrowns »

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.

I thought it would be that as well. But I went quite a while, probably almost two years, without ingesting milk at all. And I just had my 34th birthday two weeks ago. I figured there’s just no way I can still process milk and it turns out I absolutely can. No issues at all. Reading into it, it seems to be genetic.

https://medlineplus.gov/genetics/condition/lactose-intoleran...

You just either get the right genes or you don’t. I’m curious as to how long into my life I’ll be able to drink straight cow milk and be fine. Still got a bit of experimental time left. Hopefully, anyway.

Also both my parents can drink milk without issues.

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

#149

Post by ssnistfajen »

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 something. Koreans eat lots of fermented vegetables, yet why are 70%-100% of Koreans estimated to be lactose intolerant? Why are you suggesting lactose intolerance is some new condition that arose as a product of modern life? Lactose intolerance is simply the default setting for the majority of humans around the world for most of history.

Yogurt/kefir occupies very large segments in most developed countries' grocery store shelves and new brands/varieties pop up every year. How has this industry not collapsed if "a lot of people outright refuse yogurt" according to you?

The development and marketing of lactose free dairy products in recent years is simply the dairy industry exploring new market segments, because substantial portions of the population do not have lactase persistence. Even societies whose culinary traditions involved heavy consumption of dairy do not have 100% lactase persistence. It's not some weird conspiracy aimed at making modern humans "weak". The lack of lactose is not significant enough to change the nutritional content of dairy products.

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

#150

Post by wtetzner »

dagw wrote: post #49
wheelerof4te wrote: post #41

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.

Maybe a varied diet is what’s causing the problem.
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