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Reports of the death of dental cavities are greatly exaggerated (mcgill.ca)
196 points by Gadiguibou 56 days ago | hide | past | favorite | 163 comments



> We are thus left with a product, Lumina, that cannot guarantee the prevention of future caries

"Guarantees" are not strictly needed. What matters most is whether there is a substantial reduction of future caries, not whether it makes you totally immune to it.

Say, if Lumina/BCS3-L1 "only" reduces cavities by 50%, it is already half as good (arguably) as a drug which prevented 100%. This would already be large progress for such a massive global problem. The article author does not seem to recognize the potential of such a drug.


I feel like this is a trend in online writing lately, and it's leading me to more and more withdraw from online discourse. Whenever someone introduces something that greatly helps with something, there are a bunch of people who start pointing out that, while the new solution is waay better than anything before it, it's not 100% perfect, and therefore "it's benefits are exaggerated" or similar. If the new thing is in the public eye for long enough, those "exaggerated" complaints start morphing into "it's a scam", and shortly after that the new solution to yesterday's problem is the villain that must be stopped.

It's really confusing, and quite tiring.


Perfect is the enemy of the good.


I think the bigger issue is not whether it has some efficacy, even if limited (which could be interpreted as a good thing), it's the potential for the bacterium to create a mono-culture, which would be objectively bad (remember, diversity is critical in populations, and for our oral health perhaps even necessary).

So not so much perfect being the enemy of the good, fluoride isn't perfect either, but it is good. This is potentially extremely harmful, and possibly even a source of something like a new AIDS pandemic...


I'm sorry but the last claim seems extremely exaggerated.


Well literally any change removes money from some to give it to others. Side effect may be that people are better off (see Ozempic) but oh boy are the people losing money going to muddle the water / for investors as well as to fight the change.


A similar thing happened when the media learned about Ozempic (semaglutide) a while ago. Multiple progressive outlets, especially the Guardian, published articles stating the drug was overhyped, playing down its value, citing overweight women from "fat studies" academia (basically activists against the stigma of being overweight saying that being overweight itself is not the problem), emphasizing all its downsides etc. Of course they couldn't stop the hype, because the drug actually works.

Yet another example: In early 2020, for a few weeks many news sites claimed that face masks don't help against coronavirus transmission because there was "no evidence" that they did. Of course this wasn't true (the evidence was just limited, and the protection wasn't optimal), and they changed their tone quickly once multiple non-Asian countries started to introduce mask mandates for visiting public places.


See also effectiveness vs efficacy. If condoms are 100% effective but used incorrectly 20% of the time, they have 80% efficacy. It’s a useful stat when determining where to best allocate funds, but not for individual healthcare decisions.


The tone of the article is for some reason very dismissive and derisive of alternatives to plain dental hygiene. As you point out, if a simple supplement in the form of harmless bacteria could improve caries reduction by even a small amount, it seems it would be a valuable option.

There is an existing 'probiotic' that has been around for years and works the same way, and promises the same benefits, as the one described in the article, it is called Streptococcus salivarius M18, there are quite a few studies that indicate it does work to some extent [1]. You get them in the form of lozenges that you put in the mouth while sleeping and they dissolve by themselves, so not a very invasive treatment if one wanted to use it.

[1] https://www.google.com/search?q=Streptococcus+salivarius+M18


The claim of the headline is also not supported by the evidence shared in the article. As just one example, the article notes that many different strains of bacteria are responsible for caries. This fact doesn't necessarily say anything about the effectiveness of Lantern's treatments - although it might shed light on the mechanisms that make it effe tive (or not).

That's what the clinical trials and studies on the early adopters are for. There's lots of interesting commentary on the early research, such as Scott Alexander's write-up, that are much better than this article.


> The tone of the article is for some reason very dismissive and derisive of alternatives to plain dental hygiene.

Yeah, emphasis on "plain". It's proposed as an addition, not an alternative, to conventonal tooth brushing.

Streptococcus salivarius M18 seems also interesting, but its results in preventing caries are much more limited, from what I can tell. It also has be taken continuously (once per day), instead being a one-time application like BCS3-L1.


> The tone of the article is for some reason very dismissive and derisive of alternatives to plain dental hygiene.

Putting my conspiracy theory hat on, the dental hygiene industry in the US is for-profit, like the pharmaceutical, and would rather sell you a treatment than a cure.

I tried to have a dialog with my child's dentist about nano-hydroxyapatite. I was interested in their thoughts about it, not as a replacement for fluoride based therapies, but in addition to them. Rather than having a discussion about the merits of both treatments or discussing any concerns about compatibility, the dentist adopted an attitude that was belittling and made me feel like I was an anti-vaxer. The suggested we could just not do any fluoride therapies at all.

It was very odd and alarming.


I would say the author has some more substantial problems raised in the article. From the article, it seems the people pushing lumina as that we accept something which is unlikely to solve the issue (mutans is not the sole or even the probable cause of caries, just one of many) and this strain of bacteria is likely to pickup the pathogenic genes over time for higher lactic acid production, and it is no less likely than its pathogenic counterpart to produce biofilms. So now you have a bacterium that is more stubborn, and is at best going to out-compete a narrow band of microbes, some of which might be pathogenic, until it itself becomes pathogenic at some point. Now you have the same problems, with extra moving parts introduced where things can go wrong. What happens if your body becomes sensitive to the toxin this strain produces and you end up with horrific gingivitis that cannot be readily cured?

That isn't a great sales pitch.


The article makes clear that a 50% reduction is likely massively optimistic.



It seems like FDA restrictions on clinical trials have really shot us all in the foot by depriving us the opportunity to collect data on this bacteria before it was made available as a supplement. There is clearly a demand for this product and it seems quite likely that Hillman et al could have gotten a cohort together to conduct a trial if they hadn't been faced with such extreme restrictions on testing. Why is informed consent not sufficient for participation in a RCT?


Because the participants could very easily spread it to other people. This wouldn’t just affect them. That’s why the trial was ultimately required to take place under quarantine.

It’s not even a question of whether it would spread, but whether it might spread. There’s a reasonable chance that this bacterium would, in fact, spread, and nobody has proven otherwise.

The FDA is doing its job here: it’s protecting the masses from people who believe they’re just consenting for themselves.


The FDA, however, is not regulating the spread of the 800 other known species of oral bacteria as well as presumably numerous unknown ones, which do cause some known harm. The extreme suspicion of commercially introduced anthropogenic agents seems a bit ridiculous in both natural ecology and the human microbiome. Prove this compound conclusively safe, but not these other ten million compounds we're just going to allow to run wild. Or for competitors - rely on the 'proof' of safety established in the 1920's or the 1970's before we had any idea whatsoever what we were doing scientifically. Or just rely on doctors/dentists unsupported first-principles advice - we've never demonstrated scientifically that floss works, for example.

We should all be quarantined, all the time, by this criteria. Regulatory bodies have a great cognitive bias towards fictional 'purity' of systems that are in actual scientific fact, messy and routinely contaminated in various ways.


Breathing an 80/20 nitrogen/oxygen mixture is also not regulated, yet breathing mustard gas is. So biased.


For testing, we do what we can within practical limits. What those limits should be, is where contention lies. The FDA will come around, especially if someone else does trials under less strict conditions. Won't happen today.


All of those other oral probiotics are based on published research about naturally occurring bacterial strains already present in the environment, and in some cases have the evidentiary support of human trials.

Lumina is a genetically modified bacteria. It has no research supporting its effectiveness because the original inventors never bothered to conduct a human trial; they just said that it probably works based on testing in a petri dish. (Note: lots of drugs work in petri dishes and laboratory animals. Very few go on to have success in humans.)

Notably, the founder of the current company selling it has does not have a background in dentistry or microbiology and does not understand how his company's product actually works.


> research supporting its effectiveness because the original inventors never bothered to conduct a human trial; they just

If you had read the article you would know that they did bother but the regulatory body set requirements for such a study so high that they couldn't perform it.


> The extreme suspicion of commercially introduced anthropogenic agents seems a bit ridiculous in both natural ecology and the human microbiome. Prove this compound conclusively safe, but not these other ten million compounds we're just going to allow to run wild.

With endemic organisms (or viruses) they just are going to run wild regardless of how we feel about it. There's no point in banning a naturally occurring algae because excluding it from the environment is not a practical option.

The only time when we have any strong control over what organisms are in an environment is when they don't yet exist there, but we have the ability to introduce them. This is our only technical choke-point, so it makes a lot of sense to make a big deal of that decision, and probably to be quite conservative about it. You can always let the cat out of the bag later, but you can never get it back in.


They didn’t care when they were spraying down entire cities with bacteria to test the spread of biological weapons.


Does the FDA have any actual mandate or expertise to do that, or are they just embracing mission creep?


I think their right to regulate this is similar to their right to tell labs working with smallpox that they have to run a tight ship to prevent leaks.


Didn’t they have every opportunity to conduct a trial given they started outside the US in Prospera, an autonomous zone of Honduras?

“So to start, they’ll be selling Lumina in Prospera, a libertarian charter city in Honduras. Prospera allows the sale of any biotech product under an informed consent rule: as long as the company is open about risks and the patient signs a waiver saying they were informed, people can do what they want.”

https://www.astralcodexten.com/p/defying-cavity-lantern-biow...


It may still take us some time to reach that goal, but the good news is that we have an effective solution available right now: keeping good oral hygiene is known to prevent both caries and gum disease, and takes less than 10 minutes a day for the average person.

If you need more information, we recently developed a free website to get you started: https://lifelongsmiles.hk/


My wife seems to be basically immune to cavities; I get them easily. I brush very carefully; she brushes only quickly. Our diets are the same — if anything she probably gets more sugar. We have the same water source. Etc.

Clearly there’s a lot more to this than what you’re claiming.

Unless you’d propose that all of my current problems are due to conditions while I was child or similar.


I'm the same, I brush and floss regularly, occasionally use chx mouthwash, dental disclosing tables and oral probiotics. She forgets to brush sometimes, eats more sweet. She had only one or two cavities in twenty years we've known each other. I've had two root canals and have fillings regularly. Truth be told, she doesn't drink coffee at all, I drink several cups a day. She also doesn't drink much alcohol, I have one or two beers every week. In addition to bad genetics (both parents smokers and developed gum disease) I attribute this to poor oral hygiene when I was a kid, parents didn't really control my brushing, so ended up with a lot of fillings. In contrast, we brush our kid's teeth every day religiously, almost 5, no cavities whatsoever, and she eats plenty of sweets.


How many different dentists have you been to in the past twenty years? Does she see the same dentist as you now?

I once had a dentist who claimed I had a cavity every visit. I saw him once a year, and he did little more than look at my teeth. I've since switched dentists three times as I moved around the country and my dental insurance changed, and with all three, I've gotten nothing but rave reviews about the state of my teeth. I see my latest dentist twice a year, and he does an X-ray and an intraoral scan every other visit, and on my most recent visit, he discovered that one of those alleged cavities my first dentist had filled was filled improperly and appeared to have become reinfected. Unfortunately for me, I was busy at the time and postponed treatment for too long, and now the filling has fallen out and the tooth has collapsed in on itself, requiring a root canal and a crown, which in addition to being somewhat painful, will likely set me back several thousand dollars.

If you have access to the Journal of American Medicine (JAMA), I highly recommend reading this recent review of overdiagnosis and overtreatment in dentistry[1]. If you don't have access to JAMA, you can find pertinent excerpts in this Reddit post[2], along with some interesting backlash from some thoroughly offended dentists (all of it without any real supporting evidence, of course, though some of the points brought up are worth considering).

[1] https://doi.org/10.1001/jamainternmed.2024.0222

[2] https://old.reddit.com/r/Dentistry/comments/1cql9a8/interest...


I think my current dentist might be overdiagnosing a bit, we were doing a bunch of work even though another dentist said everything was fine just a year before. My biggest regret currently is a decade old root canal done by my previous dentist that was never good and kept getting sore and inflamed in the gums. The new dentist eagerly redid the root canal a year ago but we eventually had to pull it out since a big abscess formed. Looking back, I should've extracted it sooner, since the bone was basically eaten away by lingering bacteria and I'll have to do some bone augmentation for an implant.


I'm sorry to hear that. Like you correctly mention, genetics play a big role and are unfortunately (currently?) not modifiable, and there is plenty of evidence that a restored tooth is at higher risk of further issues/loss, so prevention is the best thing you can do.

Good job with your daughter! FYI, we are working on expanding the instructions to children, so watch this space ;)


Did you have asthma as kid? I know a couple of people whose teeth are wrecked from inhaler usage. Now they tell you to rinse your teeth after using them, but didn't in the past.


No, but I do have a smaller lower jaw and wear a night guard because I do sometimes clench and grind (depending on stress levels, caffeine intake, etc). This might cause excessive wear. My mother also suffers from bruxism.


While there are indeed many factors (genetics, the specifics of the microbiome in your mouth, probably some we don't even understand at the moment) at play, oral hygiene (and diet for caries, but not gum disease) is currently considered by far the most important modifiable risk factor.


Considered by who? Dentists, or scientists? Dentists seem to be about 5-10 years behind the research on this topic. I know of a single practice that has started doing oral microbiome testing.

We know that caries are caused by acid eroding the teeth. And we know which bacterial species produce this acid, how quickly they secrete it, and how common they are. The most significant source is Strep. Mutans. Sugar is an input to this process, and Xylitol (a sugar alcohol) can kill this bacteria selectively.

Diet is probably the most significant way to affect gum disease. Gum disease is associated with systemic inflammation and auto-immunity. The same dietary interventions that are used to treat those conditions also treat gum disease.


> Dentists seem to be about 5-10 years behind the research on this topic.

Generalizations are usually not helpful, I think it really depends on the dentist. I'm not sure there are proven benefits to oral microbiome testing, except in some very specific cases.

> The most significant cause for caries is S. mutans.

The 'Beyond Streptococcus mutans' section in TFA explains that the situation is much more complex than this; even if it is, good oral hygiene and reduced sugar intake (both in quantity and frequency) are still the best way to reduce the amount of biofilm present on teeth (which is a requirement for caries formation, whether S. mutans is there or not).

> Diet is the most significant way to affect gum disease.

The current clinical treatment guidelines for periodontitis[1,2] only mention that the benefit of weight-reducing diet and lifestyle changes is unclear (for treating periodontitis, obviously), and that oral hygiene is still the most important thing you can do yourself for the prevention, and, once established, to assist in the treatment of the disease.

[1] Infographic: https://www.efp.org/fileadmin/uploads/efp/Photos/Continuing_...

[2] Source article: https://onlinelibrary.wiley.com/doi/10.1111/jcpe.13290


That is frustrating. Does she drink more coffee, tea, water, during the day? Are your stress levels higher? Did your parents have similar cavity issues?


You both probably have different mouth topologies. Maybe the wife's teeth spacing are such that the bristles in the toothbrush get in more effectively under the gumline, whereas yours need more work to reach the same nooks and crannies. it depends on how much enamel you have left as well.


My wife and I are the same way. Wife maintains very good hygiene and has much more cavitities than I do.


I'm the same as your wife.

I skipped the dentist for 18 years, and during the earlier part of that span I had pretty sparse dental habits. I went in expecting the worst, but I had 1 cavity, and it was shallow enough to be drilled no novocaine. Nowadays I just brush once a day.

Thank you for letting me brag, because the other parts of my body, like heart and lungs, are total shit.


Same.

My ADHD makes brushing my teeth daily impossible. Yet, I went to the dentist today (first time after a decade)and had only one small cavity.

My partner on the other hand brushes multiple times daily and had surgery last year, because she had a particulary bad cavity.

Some dentist say, they don't kiss their kids, so they don't infect them with the cavity bacteria, but I kiss my partner all the time for decades and my teeth never got worse from it.

There were times when I drank energy drinks and ate sweet snacks daily, didn't make it worse either.


> Some dentist say, they don't kiss their kids, so they don't infect them with the cavity bacteria, but I kiss my partner all the time for decades and my teeth never got worse from it.

This seems absurd. Almost all microbes we consume (including in supplements) are transient. It takes a LOT for a community to actually establish itself. They have to be pretty well adapted to the human oral environment


Well, don’t forget genetics. Apparently 60% of tooth decay swivels on your genes.


not a specialist, but diet is quite overrated for health, even for teeth health. Other important factors: BMI, exercise, sun exposure (natural vit D), life style/stress, sleep, ..


I brush and floss every day but the cost is not trivial. Saving ten minutes EVERY day for everyone who brushes would be a massive, massive success. Not to mention it would improve health for people who can't get into the habit.


I suspect you'll still want to brush your teeth for reasons besides cavities.


A simple salt water rinse is enough to deal with halitosis. Much easier and the effects seem to last longer than prescription mouthwashes at a sufficient concentration.

https://www.sciencedirect.com/science/article/pii/S266714762...


The study you cited actually shows that salt water was only effective for 3 hours, vs 5 hours or more for the prescription mouthwashes. Furthermore, all concentrations of the prescription mouthwashes showed significantly reduced bacterial populations with continued usage (meaning, they got more effective over time.) while the salt water rinse did not.


My parents both have fillings in almost every tooth, my sister and I have none. Neither of us did anything particularly special, my parents were quite strict about sugar (for the UK in the 80s/90s) and we brushed our teeth twice a day. I never flossed regularly, though I have started doing it more in the last few years.


Fluoridated drinking water may explain the difference.


Fun fact: I'm visiting Uruguay right now, and they have fluoridated salt here! (it's iodized as well)


UK tap water isn't fluoridated


Not strictly true: https://www.dwi.gov.uk/consumers/learn-more-about-your-water...

Quote:

The water companies that are currently required by the Secretary of State to fluoridate some or all of their water supplies are:

United Utilities

Northumbrian Water

Anglian Water

Severn Trent Water

South Staffordshire Water



Your parents probably weren't brushing with fluoride toothpaste when they were young, since it only became near-universal in the late 60s in UK.


Kids ate like crap in the 60s and 70s. Everyone in my family from that generation has dental issues. Both sides of the family. Just from drinking soda like its water.


Yes this is exactly my point. Simple lifestyle changes are really all that's necessary. I still see kids walking around drinking soda, I have to fight tooth and nail to prevent my little one from being given sweets and fizzy drinks on an almost daily basis (we moved to Czech republic, I don't want to be rude about my adopted home but the truth is they are quite behind on children's health and nutrition)


Fluoride treatments at the dentist and fluoridated tooth paste are a big factor in my area. A commenter also mentioned fluoridated water, which had the same objective, but it causes demineralization of teeth (fluorosis) and possibly behavioural / hormonal changes (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6520156/, https://www.sciencedirect.com/science/article/pii/S001393512..., https://ec.europa.eu/health/scientific_committees/opinions_l... ). I'm glad fluoridization of water isn't a thing where I live.


First, fluorosis isn't demineralization of teeth, it's hypermineralization, way on the other side of the spectrum.

Second, you'll get water poisoning before you'd get fluorosis from tap water. I challenge you to find anyone who has gotten fluorosis from tap water alone


So long as the tap water is correctly treated, it's not going to give you fluorosis, but in the event the plant breaks and no one is testing the water, it can happen

https://www.adn.com/alaska-news/article/where-water-turned-d...


Sure, their can be industrial accidents. But just because some company made a radiation therapy device that accidentally fataly irradiated people, doesn't mean that radiation isn't an effective treatment for cancer


Anti-fluoride people say the weirdest things.


"Have you ever seen a commie drink a glass of water?"


What's interesting is that there is no strong proof that flossing actually helps. The U.S. Health department had to take down their recommendation to floss because they couldn't produce evidence of its efficacy.



None of your sources are studies with a strong causal link between flossing and dental health. People who floss do have other good dental habits, so there's definitely a correlation that exists. And remember, I'm making no claims either way, I'm specifically stating the current scientific evidence. I personally floss.

https://www.nydailynews.com/2016/08/03/flossing-has-no-prove...


My motto is you only have to floss the teeth you want to keep


If you want to be inspired to floss more often, just smell your floss after not flossing a few days. Disgusting, and that's convincing enough for me.


Counter point: that's the stuff you're shoving deeper into your gum line. And to reiterate, I do floss. However, I can see potential issues with it that may counter its effectiveness.


Your heart's in the right place, but these videos are hard to watch.


Which one? I was looking forward to some awkwardness but all I can find are tutorials on teeth hygiene.


Dunno that it's awkwardness so much as the discomfort of watching someone with pretty messed up teeth forcing too-large ID brushes in between them


Thank you all very much for the feedback, it gives me a new perspective on things. We wanted to show a real case, rather than animations, because we thought it would be clearer for our patients; but we are probably desensitized to watching stuff like this. Would you prefer to see a 3D animation instead, or something else?


I actually really prefer the videos of real people doing the thing! I've literally never seen a video of how to floss - even at the dentist they show you how on a little model.

Thanks for sharing these!


I'm glad they were useful to you.


I watched all the patient videos and found them helpful. There's no substitute for seeing examples with a real mouth.

The interdental brush video is a bit more "intense" than the rest. Can't be helped: you need to show someone with teeth gaps. Perhaps move that one down in the list so newcomers start with a more gentle video?


Thank you for the feedback, I'm glad you found them helpful!

I wanted the interdental cleaning part to come first, because it usually gets neglected and it's just as important as tooth brushing.

But I like your suggestion to change the order, as that would indeed give a gentler introduction.


Another perspective, I don't mind the real videos. They are helpful. It might be easier to for some watch if the subjects had fairly nice teeth. I think animations would be less helpful.


We want clean, healthy and attractive teeth and mouths to stare at. Rather than the e.g. inter-dental mouth that triggers disgust even if realistic. Use the attractive models in the video if they have healthy teeth ideally.


Thank you for the feedback, that's a point that several commenters have brought up.

The problem with the interdental brushing video specifically is that we can't show how to use larger brushes on young healthy patients, as they don't have the spaces for it. But I will think about how we can improve that video (the comment above suggested moving it down in the page, to start with the 'gentler' videos).


This exactly. I don't think the average person is as comfortable as a medical professional at starting at videos/images of messed up teeth, injuries, disease, etc. It's not exactly what we want to stare at when learning.


Also, while I'm at it, I'd suggest maybe putting an hour or two of research into how to make content… exciting? I know you're a dentist and a software engineer, not a YouTuber, but it's worth looking up a bit about what YouTubers and entertainers know about how to hold an audience's attention. Just a few small changes can probably result in a 1.5-3x improvement in the number of people who make it to the end of a video.


Another perspective, I don't feel like these informational videos need to be exciting. For this, I feel like 'just the facts' are a breath of fresh air.


Maybe exciting is the wrong word, but compelling is a better one.

For example, just the order of how you present information matters. Compare these two approaches:

1. "If you don't floss enough, then <BadThing> may happen. Here's tips on how to floss: A, B, C."

2. "Here's tips on how to to floss: A, B, C. Btw, this can help prevent <BadThing>."

The first is better. "Boring" information ceases to be boring and instead becomes compelling when you have a strong reason to want to know the information. Thus, it's important to hook people by giving them that motivational reason to watch/listen before you jump right into a video or article. Otherwise, you will likely only retain viewers who already arrive with their own personal motivations.


The very first video, pinned to the top, is titled "Why is oral hygiene important?" and lists both <BadThing> and <GoodThing>.

The site follows approach 1 as you suggest (at least it does today).


I would be curious to know if you have any knowledge from older books on how diets affected the bacteria in the mouth?


Wild, I first read about this twenty+ years ago, maybe thirty. Oragenics rang a bell, near some university in Florida?

Also, the New York Times magazine had a piece on the Prospera island in Central America last weekend, was interesting as well. Supposed to have fewer regulations but the previous government is trying to reclaim it.

https://www.nytimes.com/2024/08/28/magazine/prospera-hondura...


Same -- I would have guessed that I read about this in the late '80s.


OP reads like a lazy ripoff of earlier debates around Lumina, principally https://trevorklee.substack.com/p/please-dont-take-luminas-a... , which I don't see acknowledged or linked at all.


To be fair I be fair I’ve seen many articles and source materials on the debate and most of it is based on an understanding of the current state of the science, which is available from primary sources and not just random substacks and blogs. I would feel totally comfortable writing one of these articles on Lumina myself without citing anything but primary research, which this article does do, and not citing anyone of the secondary sources of opinion I might have read along the way.


> in fact, it forms less than 2% of all the bacteria that cause caries

I tracked down the chain of citations here. The directly cited article (https://www.nature.com/articles/sj.bdj.2018.81) says the following:

"These caries ecological concepts have been confirmed by recent DNA- and RNA-based molecular studies that have uncovered an extraordinarily diverse microbial ecosystem, where S. mutans accounts for a very small fraction (0.1%–1.6%) of the bacterial community implicated in the caries process.[20]"

Note the sudden conversion of "implicated in the caries process" to "cause caries".

The next step in the citation chain is https://www.cell.com/trends/microbiology/abstract/S0966-842X....

"In recent years, the use of second-generation sequencing and metagenomic techniques has uncovered an extraordinarily diverse ecosystem where S. mutans accounts only for 0.1% of the bacterial community in dental plaque and 0.7–1.6% in carious lesions[14,15]."

Now the claim is merely one of prevalence!

The next steps in the citation chain, https://karger.com/cre/article-abstract/47/6/591/85901/A-Tis... and https://journals.plos.org/plosone/article?id=10.1371/journal..., do seem to plausibly provide evidence that there are other mouth-colonizing bacteria which would perform the same function as S. Mutans when it comes to causing caries, such that fully eliminating S. Mutans probably wouldn't eliminate caries entirely.

But, importantly, the citation in the McGill article doesn't much support the original claim, and this citation chain could easily have bottomed out in a completely different set of results which didn't happen to lend some (weak) evidentiary support to the high-level claim.

Also importantly, this article is committing the sin of figuring out some reasons why a treatment might not be perfectly effective in all cases, and implicitly deciding that justifies ignoring any non-total benefits (i.e. cases where S. Mutans would have been counterfactually responsible for causing caries, that could be prevented). Questions that would have been appropriate, but were apparently uninteresting:

"Does this intervention also happen to chase out other acid-producing bacteria that fulfill a similar ecological niche as S. Mutans?"

"What percentage of caries cases would be prevented by chasing out just S. Mutans with this intervention, while leaving other acid-producing bacteria untouched?"

Likely this is because answers to those questions would not really have changed the bottom line. That bottom line was written by the "unanswered" safety concerns (reasonable in the abstract, less obviously reasonable in this specific case). All of the listed safety concerns have evidence pointing in various directions. Very little of that evidence is listed, probably because it's not in a format that's legible to scientific institutions. The article does note, earlier on, "The toxicity of this Mutacin-1140 compound had not been tested. What would be the consequences of millions of bacteria in the mouth releasing this compound? The answer wasn’t clear, even though the archetypal compound in the family Mutacin-1140 belonged to was known to be very safe." This is obviously relevant evidence about the safety of Mutacin-1140. _How much_ evidence? Unasked, unanswered. (I have no idea how predictive the safety of other compounds in the same family is of another unstudied compound in that family, I'm not a biologist. But this is not an _unanswerable_ question.)

(Marginal conflict of interest: I know the Lumina founder socially. I have no financial interest in that venture or any of his other ventures. I have not taken Lumina myself.)


The safety concerns sound circular in an almost Kafkaesque manner. From what I can tell, a strain of the bacteria was found in the wild that created less acid and seemed to lead to less carries. So people thought it needed to be safer, so they instead created a genetically modified version of the bacteria. But now it couldn’t even be tested in the wild because the “safer” version had so many unknowns that even letting people experiment with it would be dangerous, since it could potentially escape into the general population and hurt people (possibly escape through activities like kissing, the article states). But the earlier strain has been out there spreading in the population for decades/centuries already.

Why not just let people experiment on their own with the original low acid bacteria if they want? It’s already there in the wild. You’re already “painting your teeth” with different bacteria when you kiss people, so why not at least let some people pick which naturally occurring bacteria they can expose themselves to instead of letting it happen by random chance?

A lot of the hype about Lumina seemed to be goofy, but the hand wringing over “painting your mouth with bacteria!” is just as bad if not worse.


> From what I can tell, a strain of the bacteria was found in the wild that created less acid and seemed to lead to less carries

I think you're confused about which changes to the bacteria were natural and which were engineered. A strain in the wild was discovered that produced a weak antibiotic that it had also developed a resistance to, but it still had the original metabolic pathway that produced lactic acid. Researches took that strain and genetically modified it to produce ethanol instead of lactic acid, and then relied on the natural antibiotic-related mutations to get this strain to replace common S. Mutans in the oral microbiomes of test subjects.

The useful non-acidic property of the strain is entirely artificially introduced. The natural mutation in the wild just allowed for outcompeting and replacing bacteria that lack it. There would be no benefit from personally experimenting with the natural non-engineered strains.


If that strain produces ethanol and can colonize the guts, then it has the potential to cause the auto-brewery syndrome. That a good reason to be careful!


> So people thought it needed to be safer

That was after they decided it needed to outcompete the existing bacterium and added a mutagen to kill it off.


But why did they decide that? It seems to be a pretty clear example of the perfect being the enemy of the good.

1. Better bacteria is found in the wild, it might be able to significantly reduce cavities. People could be randomly passing it to others through kissing, and no one is concerned about it since it doesn't seem to be harmful.

2. It’s not given to people for replacement therapy because (as the article states) people decided that a replacement therapy “needs to meet a number of criteria."

3. Except meeting that criteria makes people think the replacement isn’t safe and shouldn’t be tried.

The article is saying “of course we needed to add X characteristics to the bacteria, they were necessary in order for it to be a good replacement” and then goes on to say “of course people shouldn’t be using the bacteria with X characteristics, X characteristics might be dangerous.”


What i don't understand, is why not do animal studies?

Like sure that won't answer all questions, but it seems like it would shed some light on if other bacteria cause cavities or not, and if nothing else a basic starting point.


It mentions this in the article but JD Hillman's team did study the s. mutans bacteria in rats. The results of that research were that the rats dosed with BCS3-L1 did experience fewer dental carries.


Hard to ethically replicate the conditions of the typical american mouth on an animal model.


Anecdotal of course but because of my long-covid I have been taking a ton of Vitamin K2 over the past few years.

And all my teeth aches are gone, one less problem to worry about.

This matches reports by others that K2 seems to pull calcium out of your saliva and into your gums/teeth where it should be and makes them stronger. Maybe. It does seem to keep teeth more "squeaky clean".

https://google.com/search?q=vitamin-k2+squeaky+clean+teeth


> in fact, it forms less than 2% of all the bacteria that cause caries

The word “cause” seemed to be doing a lot of lifting


cui bono?

how are you going to make any progress if you block research and experimentation consistently into areas that conveniently line the pockets of the state-protected dental guild?


The summary at the end is pretty overt, but I like it.


I'm unable to distinguish between this narrative and the premise of "Jurassic Park"


I Am Legend is probably closer.


Nature um finds a way


Down to the island!


Or, just use oil pulling with coconut oil. simple, natural and easiest way to reverse and prevent cavities. keeping the oil in the mouth for 20 minutes (before spitting out into the sink) is also a great way to maintain silence, and develop awareness of oral process, as you can't swallow.

More generally, am highly skeptical of this whole genetic modification drive for replacement of undesirable creatures like mosquitos and screw worms and now bacteria. Sure, sounds like a great idea and may work for the advertised benefits, but look who's funding it and how keen they are on developing vectors to human blood and what other tampering may occur that would be undetectable to anyone without millions of dollars of sequencing equipment. It fits in with the biosynthetic technology drive towards transhumanism alongside nanotechnology, worth researching before jumping on the "Homo Deus" bandwagon that paints us as 'hackable animals' whose soul is due to be extinct (quoting the top transhuman posterchild N. Harari). Worth deeply investigating the other side of the story, most clearly outlined by Prof. Anita Baxas, but also see Dr. Edward Group, Dr Ana Mihalchea, Karen Kingston and Dr. David Nixon.


If this is your very first comment, I can't wait for your next one.


What’s your evidence or rationale for the oil routine? Serious question, not trolling


It probably works, but it probably doesn’t work any better than using water or some other pH neutral liquid.

There’s a good chance all it’s doing is rinsing away or diluting existing acid.


Thousands of years of test of time stood with ayurveda. also validated with citations as experiments catch up

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5654187/


>The process of oil swishing is believed to cure or control 30 different types of systemic diseases including headaches, migraine, and chronic diseases such as asthma and diabetes mellitus.

Oh come on.


They forgot to mention, it specifically only works with snake oil.


Thanks for sharing the article, will give it a read.


This went on so many tangents that it came full circle


I have a feeling that the people who would trust a product like Lumina are probably the same people who will never use flouride.


Well, you can trivially falsify this feeling by going and asking some early adopters whether they brush their teeth with fluoridated toothpaste. (Spoiler: they do.)


Since you bring up fluoride—does anyone know the state of the literature on the effectiveness of fluoride treatments? I’ve been getting them for years. But with the recent trends towards PE owned dental practices and efforts to juice their profitability, I’m more and more skeptical of anything my dentist tries to sell me on.


Seems solid to me. They can predict reduction of caries before they add it to city supply water, which still happens in China I believe.


Majority of USA has fluoridated water per the cdc website. No need to go to China if you want data for studies.


I learned about Novamin a few years ago [0], and ordered BioMin Restore [1] to give it a try. I'm now a devoted customer. There are other Novamin/hydroxyapatite toothpastes, but I only have experience with this one brand.

I think this company's latest news is the version of their toothpaste that has fluoride [2] is now FDA-approved for sensitive teeth, so they're going to be able to sell it in the United States specifically labeled to help with sensitive teeth. If you live in Canada or the UK [3], it looks like you can order this now.

Just noticed a blog post on the UK site: Why you shouldn’t over-prescribe fluoride to your patients - https://biomin.co.uk/news/article/why-you-shouldnt-over-pres...

[0] https://news.ycombinator.com/item?id=26669660

[1] https://drcollins.com/collections/toothpaste/products/biomin...

[2] https://biomintoothpaste.com/

[3] https://www.biomin-toothpaste.com/products/biomin-f-75-ml / https://biomin.co.uk/


It has recently become harder to order novamin versions of sensadyne in the US through Amazon, so I'm hoping something gets onto the shelves soon.


https://www.amazon.com/gp/aw/d/B06XK6XJBP?psc=1&ref=ppx_pop_...

Bought just this past Sunday and delivered this morning, had zero issues finding and ordering it :)


Is there any science available about that, that isn't from the company selling it?


Nature relayed one from the British Dental Journal (2023) on the acid protection granted by BioMin F. (https://www.nature.com/articles/s41415-024-7876-8)

Here's another from 2022 that compares Colgate fluoride toothpaste against BioMin F(https://shorturl.at/M4hiQ).


My HN comment, linked to as [0], was on a submission about the history of NovaMin - iirc it was originally used for soldiers in Vietnam, then came to be used for repair of teeth.

You can do your own experiment: $10 for a tube, plus $6 shipping. If you have sensitive teeth it’s worth a trial.


You can get high fluoride tooth paste (i.e. ~2% fluoride vs the 0.25% found in normal toothpaste) just by asking from most dentists. Costs about the same per bottle too.

Been doing this for years and have nearly perfect teeth due to it, flossing, and non alcohol based anti-gingivitis/anti-plaque mouth washing.

Also, people who think fluoride is bad for you or think it's not effective for teeth are exactly the kind of people I'm terrified of paying in the context of developing software. I really wish people would wear their love of homeopathy, and other psudo-scientific bullshit more clearly so they can be more easily avoided.


There's a big difference between applying a high concentration of fluoride to teeth where it's needed and then spitting the excess out vs swallowing a low concentration of flouride in drinking water and having most of it go where it isn't needed.

The issue is people (rightly imo) oppose the latter and throw the baby out with the bathwater


I also get the treatment because why risk your teeth and health at the cost of basically $50? But am still curious to know more about its efficacy.


Can you explain a little more about where your "feeling" comes from? I preordered Lumina months ago and I drink fluoridated water, brush regularly with fluoridated toothpaste, and intend to keep doing so indefinitely.


I socialize with a lot of international entrepreneurs who go to places like Prospera where Lumina was started. In those circles, it's not at all uncommon for people to see fluoride as an evil thing. I've even seen women in their dating profiles advertising that they won't date a man unless he's "unfluoridated".


Have you considered that surrounding yourself with weird conspiracy theorists and then blindly projecting their behaviors onto the population at large isn't a great idea?


I'm strongly considering it, although I can't get it where I live yet. I've never had a cavity, but I spend a lot of time doing endurance sports and very high carbohydrate intake has become the latest performance enhancer. As a result I'm often drinking a couple hundred grams of plain table sugar per week and I'd like to keep my streak of good teeth health.

If I can do that for $250 I don't see why not. They're pretty clear it's not a replacement for brushing. I think of it as preventative care (assuming it is actually safe of course).


Read the article. If you have not already, you might rethink consideration of this product.


Th article just confirms my suspicion that the worst thing is I could be out $500


My own dentist (William Drillfill, DDS) was telling me just a few weeks ago that it could be alot worse. The mid-sized boat building industry sector could take a big hit and tank the entire economy. Have some sympathy for the boat builders, how many more layoffs can our country take right now?


or, you could be infecting your mouth with a stubborn bacteria that will be difficult if not impossible to eradicate, that has the capacity to laterally acquire pathogenic genes, or through the toxin it produces, suppress other microbes which are actively beneficial. For the low cost of $500, you could end up with a lifetime of medical issues.


How is that your takeaway?

Either you didn’t read the article, or you’re blatantly ignoring that we don’t understand the long term implications of having this bacteria in your mouth and gut microbiome.

There may be no problems at all… but we don’t know. This is why FDA regulations exist. The product being sold in Prospera to skirt regulations should be a red flag anyway.

I’m not saying that it can’t or won’t work. I’m saying, be careful. If you can prevent cavities by brushing with fluoridated toothpaste and flossing, why would you adopt a potential risk that could affect your health?


Sometimes you read an article and you think "this article doesn't want me to do X, but all its arguments against X are utterly terrible. If that's the best they could find, X is probably alright."


their argument is well reasoned and significant. The very real potential of the bacteria to acquire genes that make it pathogenic, coupled with how hard it would be to eradicate, should make all but the most desperate think twice. The final nail in the coffin, should be the fact that this is not even likely to work the way it is intended to.


I googled and got multiple results that I couldn't tie with your comment. what do you reference with Prospers?


As referenced in the article, Próspera [0]. It’s a private city/private economic zone in Honduras. The NYT actually just released a great Sunday Read podcast on the city this weekend [1].

[0] https://www.prospera.co/en/visit

[1] https://www.nytimes.com/2024/09/15/podcasts/the-daily/prospe...



The article provides some reasons to think that the treatment might not be fully effective even conditional on the mechanism of action working as described, not that it won't do anything at all.


The article provides some sound reasons for why

1. infecting yourself with this bacteria may not do what it is marketed to do

2. may result in suppression of beneficial microbiota

3. is not safe against lateral acquisition of a gene that is beneficial to the microbe but pathogenic to the human host

4. there is no real kill switch

for a lot of money, you might just end up buying a lot of health issues.


They just needed to humble brag, the article wasn’t important.


I don’t think that’s the case at all - it’s a common concern in endurance sports, you really do have huge quantities of sugar.


I hope one day that the dudes eating sugar and the dudes using fluoride get into a room together, and discuss how long and often said substances are in contact with dental enamel, and at what concentrations, and then either they convert to homeopathy, or find something better to do with their HSAs.


From cavities no, but from tooth pain yes. There are so many stories of suicide because the tooth pain was so bad they could not wait and endure it.


It seems you misread the headline and didn't read the article.


Prepositions are crazy sometimes, right?


Wow, the FDA is worse than useless. So much regulatory red tape. These guys had every single reasonable safeguard in place and the FDA kept putting requirement on top of requirement until literally no one would qualify for the study.

20-30 years later and humanity has had precisely zero benefit because of the FDA's simply absurd, technically impossible level of overcaution in this scenario.

It is incredible how much medical innovation is being held back because of these sort of politics. I hope the people that constantly cheer on more regulation or the FDA itself take a look at cases like this and hundreds of other similar cases where companies have simply given up on safe, promising approaches due to the regulatory red tape.


As somebody else pointed out above, the FDA is doing its job here. Putting random bacteria into peoples mouths could easily escape and contaminate other members of the population. With no guarantee of what this bacteria could potentially do in the wild, there is need to be cautious.


Sometimes red tape is good in situations that might affect a large part of the population. Remember the whole Thalidomide situation.


When red tape makes drug development and testing impossible, as it did here, the system has ceased to benefit humanity and is causing nothing but stagnation and long-term suffering (by virtue of holding back potentially life-improving or life-saving treatments.)

Enabling medical progress is far more important in the long term for our species (and to reduce suffering) than adding the umpteenth killswitch/safeguard for an ostensibly safe medicine.

But FDA regulators have no incentive in the positive direction, only in the negative direction. The more drugs they deny, the less likely they can be blamed if something goes wrong; the more requirements they add, the more secure their careers - humanity's medical progress be damned.


It is unfortunate that the only way to get through the regulatory process is copious $ - but it does work. If this project were better funded, it would likely have gotten through.

There is an entire political party representing something like half the population of the US dedicated to shrinking the regulatory apparatus, including the FDA. That doesn't sound like career security to me.


Why is all of humanity gated by the FDA? The FDA doesn't regulate every jurisdiction on the planet.

Go take it to some other country if the FDA is the problem.

Why didn't that happen here for many decades?


Some (most?) countries first wait for FDA’s decision before performing their own (lighter) reviews.


Left out of this rant against the FDA is that the original product failed because it wasn't effective enough in rats to justify the expenses of a human trial.

There was a slight, statistically significant decrease in cavities. That's meaningful at the population level, but at the individual level you're better off just using mouthwash or flouridated toothpaste.


> Left out of this rant against the FDA is that the original product failed because it wasn't effective enough in rats to justify the expenses of a human trial.

Source? The article says something else.




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