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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/



>> 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.


> long enough for a natural life

What does this mean though? Ancient lifespans were actually quite close to modern American lifespans. They likely had higher childbirth mortalities so the average may have been low but the modal lifespan was around 70 years[0] which is right around in line with the modern American. Lifespans were significantly shorter in medieval Europe but that was probably the lowest it's ever gotten and that was a relatively short period in human (or at least Western) history. Yet we still find fossil evidence that early hominins and early humans generally had great dental health.[1] Even the Romans, peasant and nobility included, did.[2]

[0] https://theconversation.com/hunter-gatherers-live-nearly-as-...

[1] https://www.npr.org/sections/health-shots/2013/02/24/1726888...

[2] https://www.docseducation.com/blog/ancient-romans-had-health...


I think that we're going to discover that "scorched earth" techniques which indiscriminately decimate bacterial populations do more to perpetuate the problem than to fix it.


Dog food isn't very optimal for dogs...

Most wild dogs would eat almost exclusively fresh raw meat.

Whereas dog food tends to be dried meat with lots of corn as a filler. People wouldn't be able to afford 100% meat dogfood, because dogs eat a lot.


> Most wild dogs would eat almost exclusively fresh raw meat

Is that right? I understood most wild dogs eat a fair proportion of roots/berries and other herby stuff. A quick dig around:

"Unlike cats, dogs aren’t obligate carnivores. They can and do eat vegetable matter. Wild dogs will search for rotten fruit and will eat the semi-digested contents of their prey’s stomach. Some will dig up vegetables and eat grasses and herbs"

https://honeysrealdogfood.com/in-the-wild/


I'm not sure where that data is sourced from... Notice it's on the website of a dog food company, who I suspect has an incentive to tell owners that the veg in the dog food is 'natural'.

I suspect if dogs do eat vegetables in the wild, it's only if they can't get enough meat, since their domestication has made them less good hunters. Their wild counterparts, grey wolves, don't seem to ever eat vegetation (except when sick).


Fair enough but I've heard this (wild dog herbivory) from several sources. I can't find better, sorry.


wolves in the wild's diets are usually around 40% plants but of course that can vary widely from area to area. I'm sure wild dogs are pretty similar


Well, the coyote poop around here often has a lot of of berries in it.

And our dogs will actively eat grass sometimes, but that's probably more about upset stomachs.


> because dogs eat a lot.

Uncooked meat does not have near as many digestible calories density wise as cooked grains. Of course it would be a lot harder for them to become overweight, but the food cost would be tremendous. Remember that obligate carnivores that weigh a lot, like tigers, are incredibly expensive to feed.


> Uncooked meat does not have near as many digestible calories density wise as cooked grains

That seems very unlikely, what with fat and the lipids in cell walls - got a source?


"Our observation that mice fed cooked meat retained higher body mass despite lesser intake (fresh- or dry- weight basis) indicates that cooking increases the energy extracted per gram of meat fed. This finding contrasts with the predictions of conventional nutritional assays, which on the basis of the Atwater system, return roughly equivalent metabolizable energy densities for raw and cooked meat on a dry-weight basis (Table S1). The problem with the Atwater system is that it ignores changes in di- gestibility, costs of digestion, and costs of immune defense, all of which are likely influenced by food processing. The result is nu- tritional inaccuracy. For example, cooking is known to increase the proportion of starch digested at the terminal ileum before access by most gut bacteria (2). Starch that resists digestion in the small intestine delivers only a proportion of its metabolizable energy to the consumer, because the short-chain fatty acids produced during bacterial fermentation of starch generate less ATP than the glu- cose produced by starch hydrolysis in the small intestine. Addi- tionally, the fatty acids are consumed as fuel for gut bacteria, and there are further losses from the production of combustible gases (40–42). Cooking, thus, increases the energetic value of starch to an extent greater than is represented by the Atwater system. Such differences between the calorie values determined by the Atwater system and the physiological outcomes observed in this study are relevant for the manipulation of diets to increased or decreased caloric loading."

* Energetic consequences of thermal and nonthermal food processing Carmody, R. N., Weintraub, G. S., Wrangham, R. W., Proceedings of the National Academy of Sciences2011 / 11 Vol. 108; Iss. 48

* https://booksc.org/book/37997813/2fc522

Note that the 'Atwater' system is referring to the traditional method used to determine caloric content created in the 1890s which burns food and measures the heat obtained from it.

Here is an interesting article about this issue:

* https://www.economist.com/1843/2019/02/28/death-of-the-calor...

I apologize for the single source -- I believed that the science was far more settled on this issue than it appears to be. Regardless, I hope it proves informative for further research if you decide to pursue it.


> We are terrible owners who don't take care of their dental hygiene

Rope toys are great for cleaning their teeth continuously if you don't feel like brushing them. You will need to throw the toys away once a year though.


Do you feed your dogs kibble?

It is not a natural diet.

Horses likewise are typically eating a very unnatural diet, typically hay.

These are both perfect examples of a analogous diet to modern human diet. The difference being that they are animals and have no ability to correct for poor dietary "choices" with proper maintenance.

I agree, however, with your self assessment.


> I agree, however, with your self assessment.

Didn’t take long to go from glib self deprecation to judgy spectator sport.

Okay holier than thou pet owner, you tell me how I’m supposed to not feed my pup kibble. She has a prescription low fat diet and there are two vendors total who supply the prescription. One supplies only kibble. The other supplies kibble and canned food. She will only eat a few bites of the canned food each day. Should she starve because the kibble isn’t natural? The canned food isn’t either, should she just starve? Should I feed her chicken and rice which even with all the fat trimmed off is still too rich for her? Or should she be set free to eat whatever she can get sick on or get hit by a car trying?

I’m doubtful my pup will have rotten teeth at 13 because she’s fortunate that dental health has been among her better strokes of luck. But I’m sure as hell going to feed her the “unnatural” food she depends on to have a healthy life and not feel guilted by judgmental busybodies about it.


It was a bad assessment and a poor comparison.

It's illogical. Your statements are also illogical and emotional.

Figure it out. Dogs can eat just about anything. Kibble is a lot of dried out garbage. Vets are great at selling you stuff and you seem to be a good customer. That's the only compliment I can afford you.

The alternative to not eating kibble is starvation? This is senseless.

I'm no busy body, in fact, I think it somewhat of an admirable trait to tell animal neglectors that they should be better to their animals. But, do feel judged if you choose to air your negligence and someone tells you, rightly, that you are in the wrong.


You’re making so many wrong assumptions to arrive at your conclusion.

> Vets are great at selling you stuff and you seem to be a good customer.

They didn’t sell me anything. They don’t stock the food they prescribed, they named two brands that offer a diet consistent with the prescription and recommended ordering from Chewy. The only relationship they have with Chewy is to confirm the prescription so orders can be filled.

If anything, my vet has been exceedingly conscious of financial impact of vet care. They’ve not only detailed when certain tests or treatments are optional and a judgment call for me to make, but have recommended against certain options as unnecessary, only telling me of those options so I can make an informed decision.

> The alternative to not eating kibble is starvation? This is senseless.

The alternatives were either:

- ignore their medical advice and let her continue to be acutely ill with a high likelihood of chronic illness

- try the prescription diet, which the vet acknowledged may not be sufficient but said it was where we should start; it has been sufficient for nearly a year, the longest stretch of time without any illness in my pup’s three and half years

- try non-prescription options, including home cooked foods like chicken/rice/vegetables; in fact this was part of the diet transition and even chicken breast with all the visible fat trimmed off was too rich for her

- try to change her taste so she won’t eat the kibble, while watching her under-eat with no way of knowing whether or how long that will continue; even with the kibble she’s a very finicky eater and always has been, and I often have had to resort to hand feeding her so she’ll be comfortable enough to eat

> But, do feel judged if you choose to air your negligence and someone tells you, rightly, that you are in the wrong.

With the help of my vet’s care, have got my pup back to health, and kept her healthy. You’re sitting here calling me negligent because you believe I’ve been swindled by an unscrupulous vet and because you think you know better than they or I do what my pup should eat. You are in fact being a busy body. And quite ignorantly so.


> Okay holier than thou pet owner, you tell me how I’m supposed to not feed my pup kibble

No need to take it personally. I don't think they were judging you for feeding your pup kibble at all. Just that it's not a fair representation of a "wild animal on a natural diet"


You should re-read GP for context.


You should reread.

None of what I had stated was directed at your bizarre situation. You have internalized some kind of trauma about your dog and chose direct those statements at yourself.

Get help or something


I’ve got plenty of help thanks


The natural diet of dogs is table scraps. They’ve been eating human leftovers for thousands of years.


The natural solution for dogs which need a special restrictive diet to survive is death. I think we prefer unnatural sometimes.


I wonder how many people, upon observing people feeding dogs table scraps, argued that it was more natural for them to hunt prey, and hide from humans unless they were a present danger, and kill or maim them in those cases.

I’m glad my pup has medical professionals who take her well-being seriously and don’t think whether she gets to live a healthy life is up for abstract debate based on how her ancestors were domesticated.

Thanks for the discussion of how unnatural it is for my pup to be alive and healthy. I’m much more educated now.


I went to an exhibit of an excavation of an old (4th/5th century) settlement in the Adriatic and it detailed every single skeleton pulled out of the different cemeteries. The interesting part for me was that almost every single one of them had bad teeth -- caries and periodontitis.


Go back another 2000 years or so, and nearly every one has great teeth...

The switch of grain-based diets is suspected to be a big part of the cause.


AFAIK, Ötzi (3230 BC) had cavities.


well, Ötzi ate wheat..


Yup makes sense. From what I've read, the switch to relying on more starch in our diets played a big role and that's a population that very much relied on a select few primary crops

It's important to remember that hunter gatherers had much more diverse diets than agriculturalists (and therefore also much better food stability). I would posit that any member of a primarily agricultural society had terrible teeth. But we generally see this less in non-agricultural diets

That being said, when you have Inuit people eating mostly meat with moss being a major plant source and Ryukyuan people turning an extremely poisonous plant (cycads) into everything from flour to alcohol, it's important to note that ANY generalization about human diets (and the health outcomes heavily affected by those diets) is hard to generalize




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