Don't rinse with water straight after toothbrushing

[f0ok]

From "Potential fluoride toxicity from oral medicaments" (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5651468/):

"The beneficial role of fluoride for the maintenance of good oral health has been known for many decades and strongly evidenced by scientific research. However, it must be emphasized that tooth decay (dental caries) is not caused by fluoride deficiency and fluoride supplementation will never reverse the active or gross carious lesions. Since the level of safety of fluoride is low, products that contain a high level of fluoride should be stored and used according to the recommendation and should be monitored by a qualified dental professional especially in children and pregnant women. In children, the swallowing reflex is not very well developed and the fluoride containing dental products are flavored hence increasing the possibility of a child to consume an excessive dose of fluoride."

Maybe swallowing fluoride is not such a good idea?f

(Also, can someone compare toxicity levels of lead versus fluoride?)

[crooked-v]

Most toothpaste has about 1000 ppm of fluoride (0.1%), which isn't a "high level" - in fact, it means that one blob of it on a toothbrush has about the same fluoride content as a large glass of fluoridated water.

"High level" in this case comes in with fluoride rinses or specialty toothpaste, which can have 5000+ or 10000+ ppm of flouride.

[xenospn]

So I'm supposed to leave the toothpaste in my mouth? For how long?

EDIT: I'd also like to point out that I have been rinsing my mouth after brushing for the last 40 years, never used mouthwash, and never had a cavity.

[jshevek]

You may have higher levels of calcium in your saliva than normal. I know someone who has poor dental hygiene practices and never had a cavity, partly due to excess calcium. Instead of cavities, he has problems with calcium deposits accumulating in his plaque.

My point is, you may simply be an outlier rather a meaningful counter example.

[rococode]

I'm not sure if this is correct but when I was in college I noticed a couple guys who just spit and didn't rinse at all. Like, ever. They just brush, spit out some toothpaste, and then move on to the next step of their routine.

At the time it seemed kinda freaky to me since I always rinse the toothpaste out when I finish brushing, but maybe they were doing it right... I can't get over the feeling over toothpaste stuck in my mouth, though. Perhaps it's one of those things that's hard to change once you establish a pattern in childhood.

[cameronbrown]

You can spit but don't add water. That should get rid of most of it.

[ianai]

“Don't rinse your mouth immediately after brushing, as it'll wash away the concentrated fluoride in the remaining toothpaste”

Sorry but that’s unacceptable to me. Come up with a better way for me to clean my teeth or I’ll keep rinsing immediately.

I do actually do this with fluoride and alcohol free mouthwash though. That’s easier to not rinse for 30 minutes.

[stygiansonic]

Also from the article: "It's best to floss before brushing your teeth."

[zzleeper]

Why? I would have thought it makes more sense to brush, then floss, then wash at the end so the fluoride stays longer

[latortuga]

I use a toothpaste for sensitive teeth due to some recessions (due to hard brushing, don't push so hard kids!) The dentist and manufacturer of the toothpaste both recommend you don't rinse post-brush to ensure the numbing agent stays on your teeth.

[climb_stealth]

I can very much recommend an electric toothbrush against brushing too hard. Depending on the model it lets you know when you push too hard. It has helped me a lot.

Also, according to my dentist the receded gums don't grow back which is quite scary.

[staplung]

Note that the rationale is that it washes out most of the lingering fluoride, which is presumably more of a concern in the UK where the water isn't fluorinated.

[asdff]

In the US, drinking water supplemented with fluoride for this very reason, so feel free to rinse out your dislodged food scraps after brushing and ignore this advice from the NHS.

[nabla9]

In some areas there is too much of fluoride naturally and it must be removed, not added.

Geographical areas associated with groundwater having over 1.5 mg/L of naturally occurring fluoride, which is above recommended levels https://en.wikipedia.org/wiki/Water_fluoridation#/media/File...

[jonathanbull]

Water in the UK is also supplemented with flouride. I think the point is that toothpaste contains more.

[jml7c5]

In the United States, recommended fluoride levels in drinking water are 0.7ppm, whereas toothpaste is 1000ppm - 1500ppm.

So even with fluoridated water you want to avoid rinsing.

[noname120]

Do you have more information on this? I thought that fluoride was toxic and thus shouldn't be swallowed. Are the quantities too small to harm you yet sufficient to prevent the formation of caries?

[VerDeTerre]

Fluoridation is by no means universal in the US—around 69.2% of public water in 2006, according to Wikipedia[1]. In some areas, resistance is strong and cuts across diverse political orientations. Portland's 2012 attempt to fluoridate, for example, drew opposition on the basis of libertarianism, environmentalism and science skepticism.

[1] https://en.wikipedia.org/wiki/Water_fluoridation_in_the_Unit...

[monadic2]

Unless of course you drink filtered water.

[gumby]

Interesting advice. Also interesting that it used inches rather than metric. Is that common?

[mdesq]

That's why my dentist recommends a fluoride mouthwash after brushing.

[avocado4]

My routine:

1. Floss 2. Waterpik (water + mouthwash) 3. Electric brush, no rinsing

[luckydata]

waterpik should do the job of flossing already, you can probably skip step 1, at least according to this study:

https://www.ncbi.nlm.nih.gov/pubmed/24282867

[gwilliams]

This advice ought to be printed on every tube of toothpaste.

[Brakenshire]

British people have healthier teeth than Americans, you’re mistaking the results of invasive and often damaging cosmetic dental procedures with the actual function and health of the teeth.

[pilsetnieks]

Brits statistically have healthier teeth than Americans. Not whiter or straighter for those who can afford it, but healthier.

https://www.bmj.com/content/351/bmj.h6543

[dijit]

British people actually have quite healthy teeth.

They are, however, famously unattractive.

[caillancm]

The main point, about not washing, isn't standard dental advice and widely known, unless I'm mistaken. Personally, toothpaste tastes so bad I find it hard not to rinse without gagging.

Otherwise, the advice is direct and the writing style is of interest in itself. So many websites that provide health advice are condescending. This one is at least instead straightforward. For example, the points about fluoride concentration are not obvious and deserve a hearing. I say at least, because they should have references and make it transparent how these conclusions were arrived at.

[YawningAngel]

I'm sceptical of this source. The post claims fluoride in toothpaste (which isn't even ingested!) is a neurotoxin and refers to a review which I cannot find (https://scholar.google.com/scholar?hl=en&as_sdt=0%2C5&q=lanc... doesn't come up with much, closest I got were https://www.thelancet.com/journals/laneur/article/PIIS1474-4... and follow-up https://www.thelancet.com/journals/laneur/article/PIIS1474-4..., neither of which discuss fluoride toxicity in toothpaste). I think we should take this author's claims with a generous helping of salt.

With that said, I wouldn't eat the stuff, but this post goes a lot further than that.

[crooked-v]

Enough flouride to cause long-term health issues takes at least 2 mg/liter of water (probably more) over a long period of time, while artificially fluoridated water standards are 0.7 mg/liter. Even many rivers and lakes have a natural fluoride content of 0.3 mg/liter.

While there is risk from fluoridated water in some places, generally this is from unusally high natural fluoridation, from minerals leached from rock exposed by volcanic shifts or badly-regulated mining.

[SquareWheel]

This is dangerous advice. Fluoridated toothpaste is incredibly important for the health of your mouth. The source you've provided is highly suspect, and the claims contradict mountains of evidence of fluoride's safety.

[acidburnNSA]

I looked into one of the references...they put 120mg/L in mice and found it to be bad. Drinking water has about 0.7 mg/L. This is a factor of nearly 200x on concentration and another lot on body mass. Shoot, if I drink 200x more water that will cause problems too!

Concentrations matter.

[kalium_xyz]

>Don't rinse your mouth immediately after brushing, as it'll wash away the concentrated fluoride in the remaining toothpaste.

That is the point.

[sillysaurusx]

It's weird that we don't know what teeth were like before fluoride was invented. The knowledge isn't directly accessible to everyday people. Sure, we know some examples, but what about the averages? Was everyone's teeth just completely screwed, all the time? How could evolution work that way? We need our teeth to eat.

It's further complicated by the invention of processed sugar, which ruins teeth. Before that, presumably it wasn't quite as bad to live without fluoride. But again, the knowledge seems kind of hard to find.

Anecdotally, I lucked out by not listening to a dentist when they said one of my teeth had to come out. Still have it six years later, and it's fine. Apparently it was a rather intense toothache that eventually went away.

[crooked-v]

> Was everyone's teeth just completely screwed, all the time?

Well, often, yes. See, for example, the history of pre-modern dentures, which were common for people in only their 30s and 40s (George Washington's teeth all fell out before he even reached 30!).

> How could evolution work that way?

Two reasons:

First, if you've had children, you're surplus material. Most people throughout history who have had children have done so by the age of 30 or 40, and so after that, their teeth just don't matter, evolution-wise.

Second, humans evolved in an environment with very limited access to sugar and acidic foods. Sugar and acidic foods are the main cause of cavities, and have been common since the invention of civilization and extremely common since the advent of mass industrialization.

> Still have it six years later, and it's fine.

It's probably not fine. It's entirely possible to have teeth that are apparently pain-free right up until they literally snap in half from deep cavities.

[Darmody]

We do know how bad teeth were a century ago. There's even evidence that humans several thousands of years ago didn't have as many cavities as we do today because of their diet.

I'm not in a position to give you advice, but be very careful with your teeth. A tootache can lead to an infection that if not treaded may kill you.

[HenryBemis]

Considering that "back then" (e.g. 2000 years ago) people didn't consume sugar, soft drinks, and their food was mostly natural and sparse (no 3 meals and 2 snacks), plus the fact that people didn't live to 100yo, I would assume that tooth decay was less of a problem.

Interesting article for about 12,000 years ago: https://eu.usatoday.com/story/news/nation/2014/01/06/tooth-d...

The comparison to London 200 years ago is astonishing, sugar is bad for us a hundred different ways!

[jshevek]

If a dentist recommends a treatment, I always get a blind second opinion. I've had many alleged cavities, which allegedly needed filling, go undetected and untreated by the next dentist. 5-10 years later, I'm convinced the dentists who claimed I needed fillings were so eager to make money they jumped the gun.

[xenospn]

I think wild animals in nature have pretty much perfect teeth - they don't eat sugar. Same with people in remote parts of Africa (whenever I see a photograph from national geographic, everyone seems to have perfect teeth).

[quickthrowman]

> Was everyone's teeth just completely screwed, all the time? How could evolution work that way? We need our teeth to eat.

Grains have sugar in them that cause tooth decay. You can blame agriculture, mostly.

[elfexec]

> It's weird that we don't know what teeth were like before fluoride was invented.

We have teeth from fossils that are a few thousand years old all the way to over a million years old.

https://www.npr.org/templates/story/story.php?storyId=129562...

https://www.smithsonianmag.com/science-nature/oldest-human-f...

https://www.nationalgeographic.com/news/2018/01/oldest-human...