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Microbes that cause cavities can form superorganisms able to ‘crawl’

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71–80 of 157 posts

Re: Microbes that cause cavities can form superorganisms able to ‘crawl’

#71
post #58
post #35

Earlier quoted context omitted.

I have a hypothesis for why this happens. Sexual reproduction has a very neat property: Recombination. Two individuals that each have one harmful mutation can through recombination have offspring without either of them. This allows removal of harmful mutations from the gene pool without terminating someones entire lineage - important when every generation comes with a decade of mutations, unlike microorganisms that a…

> > In the last 190 million years, the number of genes on the Y has plummeted from more than 1,000 to roughly 50, a loss of more than 95 percent. How much of this has happened in the recent human history? Are we becoming less “manly”?

Not really. The y-chromosome started out as a tiny variation of the x-chromosome. So all those genes were duplicates of genes on the x-chromosome.

Re: Microbes that cause cavities can form superorganisms able to ‘crawl’

#72
post #46

Earlier quoted context omitted.

A fascinating field of inquiry. Digestive systems and their inhabitants have evolved over millions of years. I recently shifted my mindset to feed not just for me, but also for the ~2kg of microbiota [1] inhabiting my digestive system. Has been great for my health. [1] https://www.racgp.org.au/afp/2017/april/the-gut-microbiome/

So glad to hear it! These microbial communities play a critical role in our health, so we should feed them accordingly. We're trying to help educate on the same behavior for the oral microbiome. There's a lot of focus on what not to eat (sugar, etc.), but not on what we can eat to improve our oral health. We wrote an article on it here [1]. [1] https://www.bristlehealth.com/post/improve-your-oral-microbi...

I found your article well intentioned and organised but frustrating, because it contains not enough examples for the non expert public it addresses. E.g. what are examples of "sticky and starchy foods"?

Re: Microbes that cause cavities can form superorganisms able to ‘crawl’

#73

Years ago, I recall reading about a putative Cavity Vaccine which was a bateriophage which targeted the tiny fraction of species present in the mouth responsible for tooth decay. Supposedly, a one time inoculation would confer lifelong protection. It has been decades and I have not heard anything more about this. Big Dentist keeping the research down or was there some "in mice" kind of gotcha which limited the treatm…

https://marginalrevolution.com/marginalrevolution/2020/09/th...

Re: Microbes that cause cavities can form superorganisms able to ‘crawl’

#74
post #29

The evolutionary adaptations oral bacteria have developed to coexist are fascinating. Another example is the known gum disease-causing species, P. gingivalis, can suppress our adaptive immunity [1]. This finding underscores the importance of taking preventative approaches to prevent attachment of biofilm producers (and why daily hygiene is so important), and finding more approaches to biofilm destabilization, like in…

I think a very interesting field of inquiry into oral microbiota is a broad evolutionary approach. There was a study published in Nature Genetics[0] showing big changes in oral microbiota corresponding with Neolithic and Industrial dietary change. Modern oral microbiota are markedly less diverse than historic populations and the, much more developed, study of the gut microbiome shows us that very microbial diversity very often corresponds with usually-commensal microbes becoming pathogenic. It seems that cariogenic bacteria became dominant, apparently during the Industrial Revolution.[0] But we know that pre-Neolithic hominins very rarely had caries.[1] Despite affecting anywhere between 60-90% of schoolchildren in industrialized nations, less than 3% of P. robustus specimens examined had dental caries.[1]

What's MOST fascinating to me is that this dance isn't just our mouths vs the microbiomes. There's now considerable evidence that it is more likely to be the host response to the bacteria that leads to the tissue changes noted in gingivitis and periodontitis[2]

[0] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3996550/

[1] https://www.sciencedirect.com/science/article/abs/pii/000399...

[2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3692012/

Re: Microbes that cause cavities can form superorganisms able to ‘crawl’

#75

Anecdotally, I’m having one hell of a time with my 3yo and 5yo’s teeth. No juice. No soda. No bad snacks. Lots of dentist recommended foods and snacks. Full brushing and flossing regimen. Fluoride. Dentist applied special fluoride treatments. Trust me when I say we’re doing everything right. And yet they’re 3 and 5 and have had so many cavities. I asked my dad about it and he said my brothers and I had, frankly, poor…

> I cannot shake the feeling that something significant has changed in the last 30 years.

Try the past few hundred years: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3996550/

> The composition of oral microbiota remained surprisingly constant between Neolithic and Medieval times, after which (the now ubiquitous) cariogenic bacteria became dominant, apparently during the Industrial Revolution. Modern oral microbiota are markedly less diverse than historic populations, which might be contributing to chronic oral (and other) disease in post-industrial lifestyles.

Re: Microbes that cause cavities can form superorganisms able to ‘crawl’

#76
post #29

The evolutionary adaptations oral bacteria have developed to coexist are fascinating. Another example is the known gum disease-causing species, P. gingivalis, can suppress our adaptive immunity [1]. This finding underscores the importance of taking preventative approaches to prevent attachment of biofilm producers (and why daily hygiene is so important), and finding more approaches to biofilm destabilization, like in…

1. I heard that oral health either predicts or is a causal effect in dementia and Alzheimer’s. What’s the mechanism?

2. Should we be having micro biome implants? And more ridiculously, but not really, should we have “celebrity micro biome” products?

Re: Microbes that cause cavities can form superorganisms able to ‘crawl’

#77
post #46

Earlier quoted context omitted.

A fascinating field of inquiry. Digestive systems and their inhabitants have evolved over millions of years. I recently shifted my mindset to feed not just for me, but also for the ~2kg of microbiota [1] inhabiting my digestive system. Has been great for my health. [1] https://www.racgp.org.au/afp/2017/april/the-gut-microbiome/

So glad to hear it! These microbial communities play a critical role in our health, so we should feed them accordingly. We're trying to help educate on the same behavior for the oral microbiome. There's a lot of focus on what not to eat (sugar, etc.), but not on what we can eat to improve our oral health. We wrote an article on it here [1]. [1] https://www.bristlehealth.com/post/improve-your-oral-microbi...

Interesting how this article points out that foods like fish and eggs are high in sulfur contribute to gum inflammation, but that omega-3 fatty acids can help reduce this inflammation. I guess that piece of salmon may counterbalance itself.

Re: Microbes that cause cavities can form superorganisms able to ‘crawl’

#78

I for one welcome our new multicellular, cross-kingdom assemblages overlords.

This blows my mind, I just this last week learned about xenobots on Lex Fridman's podcast with Michael Levin. I had no idea how fast evolution can work...

Re: Microbes that cause cavities can form superorganisms able to ‘crawl’

#79
post #74
post #29

The evolutionary adaptations oral bacteria have developed to coexist are fascinating. Another example is the known gum disease-causing species, P. gingivalis, can suppress our adaptive immunity [1]. This finding underscores the importance of taking preventative approaches to prevent attachment of biofilm producers (and why daily hygiene is so important), and finding more approaches to biofilm destabilization, like in…

I think a very interesting field of inquiry into oral microbiota is a broad evolutionary approach. There was a study published in Nature Genetics[0] showing big changes in oral microbiota corresponding with Neolithic and Industrial dietary change. Modern oral microbiota are markedly less diverse than historic populations and the, much more developed, study of the gut microbiome shows us that very microbial diversity…

>> There was a study published in Nature Genetics[0] showing big changes in oral microbiota corresponding with Neolithic and Industrial dietary change.

A different diet leads to a different microbiome.

I think mammals' teeth last long enough for a natural life. Of course we want a longer and better life.

For instance, all my dogs by age 13 yo have lost half their teeth to rot. We are terrible owners who don't take care of their dental hygiene, which I suppose makes it a more "natural" evolution. Old horses also lose their teeth, too.

Re: Microbes that cause cavities can form superorganisms able to ‘crawl’

#80

Earlier quoted context omitted.

A fascinating field of inquiry. Digestive systems and their inhabitants have evolved over millions of years. I recently shifted my mindset to feed not just for me, but also for the ~2kg of microbiota [1] inhabiting my digestive system. Has been great for my health. [1] https://www.racgp.org.au/afp/2017/april/the-gut-microbiome/

What sort of foods do you recommend? I've heard good things about yogurt, cottage cheese, and kimchi; but don't know for certain.

It appears that probiotic foods are beneficial in isolation, but my recent reading (no singular source) indicates that it’s far more effective when combined with a varied and high fibre diet.

It seems like you can do great without the probiotics too, and only ensure you have a good quantity and diversity of high fibre foods in your diet. This seems to be the cornerstone of enriching and sustaining gut biodiversity.

A lot of people think they have the fibre part down, but the science suggests most of us are nowhere near adequate intake. Around 40 grams seems like the minimum, but if you can go higher, there doesn’t appear to be a disadvantage, but there could be more benefits.

A key factor here is that fibre from whole foods is far more beneficial to the gut flora. If it’s highly processed, it’ll move through the gut too quickly. It’ll help you move stool in the case of something like metamucil, but your gut won’t derive much benefit from it otherwise.

Off the top of my head, some excellent gut foods are:

- whole grains with the hull intact (oats are great)

- all legumes

- avocados

- berries

- many nuts and seeds, but especially chia, flax, sunflower, pistachio, walnut, coconut

I land somewhere around 65 grams per day, but I’d like to do better. In the USA, the average is around 16 grams. It’s nowhere near enough to support proper intestinal motility and robust, diverse flora.

Definitely eat probiotic foods, but include as many whole, high fibre foods as you can too.

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