Take the 2-minute tour ×
Skeptics Stack Exchange is a question and answer site for scientific skepticism. It's 100% free, no registration required.

On PubMed.gov http://www.ncbi.nlm.nih.gov/pubmed?term=PMID%3A%2016979289

"Determination of exposure and probable ingestion of fluoride through tea, toothpaste, tobacco..."

"Levels of water soluble and acid soluble fluoride in tea, toothpaste, tobacco and pan masala (mouth freshener) were estimated. These items are ignored while calculating the total dietary intake of fluoride. Tea, toothpaste, tobacco, pan masala (with tobacco & w/o tobacco) expose the human body to 3.88-137.09, 53.5-338.5, 28.0-113.0, 16.5-306.5 and 23.5-185.0 microg of fluoride per gram of these items, respectively." PMID: 16979289

Per "Science Daily" July 14, 2010 "Most published reports show 1 to 5 milligrams of fluoride per liter of black tea, but a new study shows that number could be as high as 9 milligrams." http://www.sciencedaily.com/releases/2010/07/100714104059.htm

On PubMed.gov http://www.ncbi.nlm.nih.gov/pubmed/11355098

"Dental caries among 10- to 14-year-old children in Ugandan rural areas with 0.5 and 2.5 mg fluoride per liter in drinking water"

"The purpose of this study was to report on dental caries among Ugandan children residing in rural areas with either a low or high fluoride concentration in the drinking water... In one low fluoride area, Kyabayenze, all children were caries-free compared to 75% to 86% in the other areas. In Kyabayenze, tea with sugar was taken significantly less frequently than in the other low-fluoride area. In the high-fluoride district, age and consumption of tea with sugar were positively and significantly correlated with caries." PMID: 11355098

So it doesn't appear as though the high fluoride content of tea prevents caries.

On PubMed.gov http://www.ncbi.nlm.nih.gov/pubmed/15341143

"The association between environmental tobacco smoke and primary tooth caries"

"After adjusting for age, SES, toothbrushing frequency, total ingested fluoride, and combined intake of soda pop and powdered drink beverages, the relationship of smoking and caries still remained significant..." PMID: 15341143

It doesn't look like the high fluoride found in tobacco reduces caries either.

How does one make sure they aren't exceeding the "recommended level" of fluoride? The fluoride content isn't listed on tea, tobacco, iceberg lettuce, soft drinks, juice, beer, wine, wheat flour, pharmaceuticals, grapes, raisins, candy, etc. But if you take the time to research it, you find that the majority of people in the USA are exceeding the recommended levels of fluoride.

Can fluoride levels in people be determined simply by counting cavities? Or does it require lab work?

share|improve this question
Maybe young children don't drink much tea. And may be people who smoke are not that much concerned with dental health. And maybe selective quotation and pejorative descriptions ("industrial waste") don't help in the debate about fluoride. –  matt_black Dec 24 '12 at 21:45
We know there is a great deal of fluoride in coal, right? If not, see... On PubMed.gov ncbi.nlm.nih.gov/pubmed/9518433 "Health effects of indoor fluoride pollution from coal burning in China" "Because indoor fluoride from combustion of coal is easily absorbed in stored food and because food consumption is a main source of fluoride exposure, it is necessary to reduce airborne fluoride and food contamination to prevent serious fluorosis in China." PMID: 9518433 –  Skeptical Dec 24 '12 at 22:00
Skeptical- you have made this entirely unreadable for me. Can you remove all these comments and edit the question to make it possible to read, understand and respond. –  Rory Alsop Dec 24 '12 at 22:35
Your use of the emotive term "industrial pollution" is inaccurate and pure propaganda. Please remove, or find someone actually claiming that only "industrial pollution" works, so we can debunk it. –  Oddthinking Dec 24 '12 at 22:49
@Carlo: Re bans of fluoridation in Europe: This has been addressed here: skeptics.stackexchange.com/questions/10717/… –  Oddthinking Dec 25 '12 at 0:04
show 21 more comments

closed as not a real question by Rory Alsop, Oddthinking, Sklivvz Dec 25 '12 at 1:20

It's difficult to tell what is being asked here. This question is ambiguous, vague, incomplete, overly broad, or rhetorical and cannot be reasonably answered in its current form. For help clarifying this question so that it can be reopened, visit the help center.If this question can be reworded to fit the rules in the help center, please edit the question.

2 Answers

The first two papers talk about how much fluoride is ingested from various products. I haven't looked at them closely.

The third paper suggests that people who drink tea with sugar get more dental caries.

Tea with sugar.

Tea with sugar.

Tea with.


Sugar is, of course, strongly associated with dental caries. It is a confounding factor. No conclusion can be drawn about the protective effect of fluoride when there is a much larger effect masking it.

The fourth paper talks about tobacco. Now, tobacco itself contains various amounts of sugar too, but we don't even need to look at that. We can look at the abstract that was quoted.

After adjusting for age, SES, toothbrushing frequency, total ingested fluoride, and combined intake of soda pop and powdered drink beverages, the relationship of smoking and caries still remained significant.

They had already accounted for what they considered to be a confounding factor - fluoride. It is unreasonable to argue that, once you subtract the benefits of fluoride from the effects, that there is no sign that fluoride is effective.

Conclusion: There is no actual claim made by a third party in this question, so there is no way for me to summarise whether they are right or not. The question is speculating an effect that the authors of the papers didn't claim or counter-claim.

share|improve this answer
Lead is also linked to dental decay. Fluoride doesn't reduce caries caused by lead ingestion. –  Skeptical Dec 25 '12 at 0:07
Furthermore it will be difficult to find Americans not consuming sugar. Are we to assume that fluoride is ineffective when consuming sugar? How many children in America will avoid sugar, realistically? –  Skeptical Dec 25 '12 at 0:12
@Skeptical: These are non-sequiturs. The lead issue is irrelevant to the question. No, I am not suggesting that fluoride is ineffective when consuming sugar. I'm saying the effect of sugar is very likely greater than the effect of fluoride - which makes the question about American children irrelevant. –  Oddthinking Dec 25 '12 at 1:21
add comment

Why doesn't the high amount of fluoride found in tea or tobacco prevent dental caries?

Because it's not the amount in tea or tobacco that is important, it's the amount in teeth enamel that is important.

Communities considering water fluoridation are encouraged to review their individual circumstances carefully and in detail, giving attention to any available data on the dental health of community members, the size of the group not likely exposed to adequate fluoride from other sources, the minimum level of fluoride required to be beneficial


the total daily fluoride intake from all sources should not exceed 0.05-0.07 mg F / kg body weight

from Fluoride Guidelines

So as with most chemicals on which we rely (H2O, O2, C27H44O NaF/SnF2...), there is a range of intakes which are beneficial, below or above that range there may be either no benefit or harm.

Does it have to be hydrofluorosilicic acid?

Do you have a source for that claim?

No. Fluoride can be effective against caries when delivered from Sodium Fluoride, Stannous Fluoride or a variety of other forms.

the results of this study serve to lend additional support to the conclusion that dentifrices formulated with sodium monofluorophosphate provide an equivalent level of anticaries efficacy as to those formulated with sodium fluoride.

Comparative anticaries efficacy of sodium fluoride and sodium monofluorophosphate dentifrices

The fluoride in the water is just fluoride [in the ionic form]. The fluoride in the water does not know if it came from sodium fluoride or calcium fluoride or another fluoride compound [in the inorganic form, of course].

The Fluoride ion

share|improve this answer
Then that would imply that tobacco and tea "should" prevent caries, doesn't it? They both contain fluoride. –  Skeptical Dec 24 '12 at 23:58
How does one make sure they aren't exceeding the amount? The fluoride content isn't listed on tea, tobacco, iceberg lettuce, soft drinks, juice, beer, wine, wheat flour, pharmaceuticals, candy, etc. But if you take the time to research it, you find that the majority of people in the USA are exceeding the recommended levels of fluoride. –  Skeptical Dec 25 '12 at 0:05
@Skeptical: No it doesn't imply that. It implies that prevention of caries depends A) on how much fluoride the source contains. (it isn't sufficient for it to contain Fluoride - there must be more than some minimum) B) on how much of fluoride ends up in tooth enamel. C) on how much fluoride is available from other sources and D) on how much the positive effect of the fluoride is counteracted by the negative effects of caries-encouraging chemicals delivered in tea (e.g. sugar) or tobacco. These are different implications than the one you mentioned. –  RedGrittyBrick Dec 25 '12 at 0:07
@Skeptical: whilst your second comment contains an interesting question, it is irrelevant to the two questions I address in my answer (I already addressed the relevant aspect of your comment as it applies to the first Q). –  RedGrittyBrick Dec 25 '12 at 0:10
add comment

protected by Larian LeQuella Dec 24 '12 at 23:51

Thank you for your interest in this question. Because it has attracted low-quality answers, posting an answer now requires 10 reputation on this site.

Would you like to answer one of these unanswered questions instead?

Not the answer you're looking for? Browse other questions tagged or ask your own question.