8 ms·

Drinking fluoridated water during pregnancy may lower IQ in sons

88 points by tshannon 7y ago

lootsauce 7y ago
It's interesting how policies like fluoridation of water are accepted at face value assuming the highest of scientific / statistical rigor was used to justify them. Of course that is not the case. Yet it requires just that, not common sense, to even question the practice in a manner that people will not consider somehow off-kilter. Our faith in authorities is stronger than ever, while the scientific community struggles with our basic ability to reproduce much of the research we even today cite is rigorous even ground-breaking.
- geggam 7y ago
  Interesting you get downvoted for stating we should question everything to include authority. Thought science was all about questioning and reconfirming truth as more knowledge is obtained
  - lootsauce 7y ago
    I think that we are in for a new renaissance of scientific discovery as we grapple with all of the issues related to the reproducibility crisis. It will lead to better statistics, better science and more useful results. Untill then we will have people arguing with the authority of their position and "because science"
    - wysifnwyg 7y ago
      If you took a look at the study and the margin of error for their results, you'd notice that the margin of error has an overwhelming overlap.
not_a_cop75 7y ago
Old news.
- mgamache 7y ago
  People have suspected for a while, but it was not as clear as this new larger study. This is much more difficult to dismiss.
  - wysifnwyg 7y ago
    If the math was solid, you'd have a point. But it doesn't, so you don't.
    - mgamache 7y ago
      Because you know more then the editors at Jama? Without explaining why?
      - wysifnwyg 7y ago
        Returning to the math, I did the calculations and here is the margin of error for each group: 11%, 9%, 9%. Their common error (the overlapping region of area) is the interval 87.79-104.95. The IQ scores from each group (94.91, 96.29, 96.47) are well within that margin of error. If you perform a t-test on 3-Ca vs. 3-placibo you'll see that the difference is not statistically significant.
  - not_a_cop75 7y ago
    I'm sorry but if you've done even the most minimal study of fluoride levels, this is something you'd know - not because it's proven but because the extrapolated data going back from decades makes sense. To the point - the movie Doctor Strangelove even goes as far as to mock this controversy. So, I restate my claim. If you know nothing of this, then it's because you haven't researched it.
    - mgamache 7y ago
crooked-v 7y ago
This will definitely need further testing to confirm validity and to pin down the effect further, but if true, that will leave the question of whether as a society we feel the substantial dental health benefits in most areas are worth the 1.3-point IQ reduction, and if not, what we can do to counterbalance the effects of removing flouride from the water. Edit: Corrected the IQ drop amount.
- dtech 7y ago
  The average IQ drop was 1.3 points. It's 4.5 points per mg/L of fluoride and the average difference was 0.29 mg/L.
- deleted 7y ago
  [deleted]
krustyburger 7y ago
“Despite that, several researchers argue that the paper’s methodological shortcomings undercut its importance. In a statement to the Science Media Centre in London, an independent organization that sources expert opinions on science in the news, psychologist Thom Baguley of Nottingham Trent University in the United Kingdom noted the data “are very noisy,” meaning they contain a lot of other factors that could easily lead to false positives. Psychologist Stuart Ritchie at King’s College London added that the findings are just barely statistically significant, calling them “pretty weak and borderline.” By itself, the study “shouldn’t move the needle much at all on the question of the safety of fluoride,” he wrote.”
- internet_user 7y ago
  Safe treatment? Great. How about obtaining informed consent first?
  - wysifnwyg 7y ago
    If you don't like how a water treatment plant operates, you could always dig your own well or purchase a water filter to remove the fluoride.
    - tomhoward 7y ago
      The suggestion to "dig your own well" suggests your comment is not entirely in good faith, but I'll respond as if it is. Plenty of people do filter fluoride from their tap water or source non-fluoridated water for drinking. The problem is that the mainstream population is led to believe that one has to be stupid to think fluoride might carry any health risks, and therefore stupid to take steps to reduce/avoid fluoride. As someone who was raised in mainstream society by educated, scientifically-minded people, and educated/interested in science myself, I held this assumption, right up until I was given very real cause to question it. Several years ago I started experiencing a complex combination of physiological impairments, including fatigue, memory/cognition problems, mood issues (depression/anxiety), digestion problems, immune-system dysfunction, among others. After much research and testing, my thyroid function has been identified as a key factor in my illness. Research on this topic has led me to multiple studies indicating that fluoride ingestion is linked to thyroid impairment. A recent study [1], published in Scientific Reports, affirms that hypothesis, but there are many others. (Incidentally, thyroid function has been linked to IQ [2][3], so this phenomenon could well be linked to the results of the study under discussion in this thread.) I'm currently undertaking a process to seek to remove accumulated fluoride from my body and raise my iodine level (of which fluoride is an antagonist, but which is an essential nutrient for thyroid function). Time will tell if this held to bring about the desired result. But the thing is, people who aggressively and reflexively dismiss any doubts about the safety of fluoride aren't interested in seeking and dispassionately examining studies like these, which suggests their motives are far more ideological than they are scientific. Meanwhile, countless people suffer with undiagnosed or “incurable” thyroid disorders and related conditions like chronic fatigue syndrome, and are made to believe they should “just try harder” or “stop pretending to be sick”. [1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5805681/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5805681/ [2] https://www.ncbi.nlm.nih.gov/pubmed/29757392 https://www.ncbi.nlm.nih.gov/pubmed/29757392 [3] https://www.endocrine-abstracts.org/ea/0020/ea0020p115 https://www.endocrine-abstracts.org/ea/0020/ea0020p115
jonny_eh 7y ago
> Longtime fluoridation critics are lauding the study, but other researchers say it suffers from numerous flaws that undercut its credibility. Either way, “It’s a potential bombshell,” … Umm, what?
- awinder 7y ago
  What, you missed Jack Ripper's celebratory tweetstorm?
  - OrangeMango 7y ago
    Did he suggest that women drink only pure-grain alcohol during pregnancy?
word-reader 7y ago
I predict this research will receive reasoned and appropriate appraisal by the press and public officials.
- THansenite 7y ago
  Or, ya know, the real experts.....parents on Facebook.
  - jackhack 7y ago
    Well, you can do what you like but when it comes to complex medical issues my winning strategy is to wait for a Hollywood actor, famous musician, or a daytime TV host to tell me what to think.
narrator 7y ago
Drinking fluoridated water does not do anything to protect teeth. They don't have it in Europe and have dental health that's just fine. Just goes to show you can do ANYTHING with good PR. The Fluoridation campaign was headed up by Edward Bernays[1] who was Freud's Nephew and one of the greatest propagandists of all time. His other famous accomplishment was convincing women that they should smoke[2]. [1] https://en.wikipedia.org/wiki/Public_relations_campaigns_of_Edward_Bernays#Water_Fluoridation https://en.wikipedia.org/wiki/Public_relations_campaigns_of_... [2] https://en.wikipedia.org/wiki/Public_relations_campaigns_of_Edward_Bernays#Cigarettes https://en.wikipedia.org/wiki/Public_relations_campaigns_of_...
- dkersten 7y ago
  I'm no fan of mass medication without a choice (or supplementation, whatever), but what you state is not the full story: > They don't have it in Europe and have dental health that's just fine. Much of Europe (not all) doesn't fluoridate their water, but they DO fluoridate salt and milk, or have high levels of natural fluoride in their water. To quote wikipedia[1] (yes, yes, I know, although they at least have a citation[2] for it): > the European Commission finds no advantage to water fluoridation compared with topical use > Community water fluoridation is rare in Continental Europe with 97–98% choosing not to fluoridate drinking water. Fluoridated salt and milk is promoted in some European countries instead. Water fluoridation has been replaced by other modes in many countries where water supplies are too decentralized for it to be a practical choice, or existing natural fluoride levels were already ample, including Germany, Finland, Japan, Netherlands, Sweden, Switzerland, Denmark and at a time Israel. That doesn't mean they didn't find fluoridation useful, just that topical use is just as good. Personally, I dislike the idea of forcing everyone to use fluoridated products (by not providing alternatives, or by putting it in all the water) and would prefer if topical use were encouraged instead, but my preferences aside, fluoride has been proven to be beneficial to teeth. [1] https://en.wikipedia.org/wiki/Fluoridation_by_country https://en.wikipedia.org/wiki/Fluoridation_by_country [2] https://en.wikipedia.org/wiki/Fluoridation_by_country#cite_note-EU2011-16 https://en.wikipedia.org/wiki/Fluoridation_by_country#cite_n...
  - lootsauce 7y ago
dtech 7y ago
Here's the meat: > About 40% of the nearly 600 women lived in cities with fluoridated drinking water [...]. Three to 4 years after the women gave birth, researchers gave their children an age-appropriate IQ test. After controlling for variables such as parental education level, birth weight, prenatal alcohol consumption, and household income, as well as exposure to environmental toxicants such as lead, mercury, and arsenic, they found that if a mother’s urinary fluoride levels increased by 1 milligram per liter, her son’s (but not her daughter’s) IQ score dropped by about 4.5 points. That effect is on par with the other recent studies looking at childhood IQ and low-level lead exposure. So that's an average 1.3 IQ drop in cities with fluoride. For 1 gender. In an IQ test for 4 year olds. An IQ test. Can anyone with more knowledge of statistics chime in? This feels like it cannot be statistically significant with n=600, a subgroup analysis and a test I cannot imagine being even remotely accurate (IQ test for 4 year olds)
- DevX101 7y ago
  Until another replicated study comes along to dispute this, I'll take the word of the author and the editors at JAMA over your 'feel' that this isn't statistically significant. "There was a significant interaction (P = .02) between child sex and MUFSG (6.89; 95% CI, 0.96-12.82) indicating a differential association between boys and girls. A 1-mg/L increase in MUFSG was associated with a 4.49-point lower IQ score (95% CI, −8.38 to −0.60) in boys, but there was no statistically significant association with IQ scores in girls (B = 2.40; 95% CI, −2.53 to 7.33)." 1. https://jamanetwork.com/journals/jamapediatrics/fullarticle/2748634 https://jamanetwork.com/journals/jamapediatrics/fullarticle/...
  - dtech 7y ago
    I browsed the article and have a basic understanding of statistics, no need to get patronizing. The article does not state the variance of this IQ test and does not state how many subgroups they analyzed and whether they corrected for that or if they a-priory were planning on analyzing gender. Picking subgroups until you've found one that is statistically significant is a well known technique in P-hacking. Other problems: - The IQ score for girls is 5 points higher on average than for boys in the study group - Fluoridation has the opposite effect for girls, the average IQ was 1.5 points higher. It is really strange for a chemical to have a completely different effect on young girls and boys. Statistical variance is much more likely - The average IQ score in the sample was 107, well above the average 100 - Parent IQ was not a variable, only the very roughly correlated high school diploma or not and household income. "Extraordinary claim require extraordinary evidence", and this study seems to at best be an indication that further research is needed rather than iron-clad proof of this effect.
hedvig 7y ago
Does it set a cap in potential or just drop in each individual relatively?
notadoc 7y ago
Original study without the opinionated article: https://jamanetwork.com/journals/jamapediatrics/fullarticle/2748634?guestAccessKey=d027f743-0a06-4f92-ad75-807f8b8d2a5e https://jamanetwork.com/journals/jamapediatrics/fullarticle/... Going forward, it'd probably be appropriate to only post the studies and not some sleazy clickbait opinion headline "you won't believe what this controversial study says blah blah!"
wysifnwyg 7y ago
Is it just me or do the groups have a significant overlap in their margin of error?
- wysifnwyg 7y ago
  Returning to this, I did the calculations and here is the margin of error for each group: 11%, 9%, 9%. Their common error (the overlapping region of area) is the interval 87.79-104.95. The IQ scores from each group (94.91, 96.29, 96.47) are well within that margin of error. If you perform a t-test on 3-Ca vs. 3-placibo you'll see that the difference is not statistically significant. How is this study concluding these results? What math are they using?
milin 7y ago
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4418502/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4418502/ This article from 2014 classifies fluoride as a neurotoxicant.
- geggam 7y ago
  Why is a link to peer reviewed material getting downvoted ? Not liking the study is one thing but downvoting a link to material without stating a reason is willful ignorance.
  - not_a_cop75 7y ago
    It's absolutely dangerous in large quantities, like most anything else is dangerous in large quantities.
    - geggam 7y ago
      I am not a scientist and anyone who is should feel free but from what I have read flouride is a bioaccumlator. At what point does it become dangerous to continue to drink water ?
      - yarrel 7y ago
        Drowning is a strong contraindicator. There is also water intoxication, which can be deadly.
        geggam 7y ago
        From flouride was assumed... humor noted ;)
      - Sohcahtoa82 7y ago
        > At what point does it become dangerous to continue to drink water ? According to this page [0], the LD50 of water is 6 liters, so somewhere before that. [0] https://www.compoundchem.com/2014/07/27/lethaldoses/ https://www.compoundchem.com/2014/07/27/lethaldoses/
aaomidi 7y ago
I'm not against fluoridation, but it does seem weird that we're so certain about these things...until we're not. Shouldn't we stop doing one-size-fits-all medication and actually expand access to toothpaste & dentists?
- OedipusRex 7y ago
  There are drugs that help with specific complications that are just simply not made because the market for them is too small, they're call orphan drugs (https://en.wikipedia.org/wiki/Orphan_drug https://en.wikipedia.org/wiki/Orphan_drug). The drugs that make it to market are not necessarily the best at treating you, they just cover enough of the population (normally more than one ailment per drug) and can be profitable.
  - aaomidi 7y ago
    I understand these. And it pains me that they exist. I'm mostly talking about the availability of certain medication. Like, it makes sense to have a nationwide vaccine program. It doesn't make sense to have fluoridated water due to the relative ease of access to toothpaste. Especially because we really can't tell with certainty what consuming this does in the long-multigenerational term. Why should we take the risk?
    - OedipusRex 7y ago
      In my youth I lived off a well and did not have access to fluoridated water. My parents still live in that house. There are large swaths of people who live off of a well in the United States. We started adding fluoride to water because our knowledge at the time said it was a good idea (and still probably is). The rates of tooth decay falls when fluoride is introduced in drinking water. https://www.cdc.gov/fluoridation/pdf/natures_way.pdf https://www.cdc.gov/fluoridation/pdf/natures_way.pdf But the only places that have fluoride added to the water are metropolitan areas (at least around me in a Midwestern state).
      - lootsauce 7y ago
phkahler 7y ago
If this turns out to be true, I hope they'll take a closer look at the relationship between Fluorine and Iodine. My guess is the fluorine has effects that mimic iodine deficiency and perhaps increasing iodine can counter the negative effects of the fluorine. Women also need more Iodine than men, though I'm not sure if that's true at age 4 but it might explain the sex difference as well.
- gus_massa 7y ago
  It's a nice idea, but I think it's wrong. The nice part is that Fluorine and Iodine are in the same column of the periodic table, so they are somewhat similar. The problems is that between Fluorine and Iodine there is Chlorine and Bromine. Let's ignore Bromine for simplicity. The recommended intake of Fluorine and Iodine is approximately .001 or .002 g/day, and the recommended intake of Chlorine is 1 or 2 g/day. (With a lot of simplifications. For a serious number ask your medical doctor.) So the intake of Chlorine is almost 1000 bigger than the intake of Fluorine and Iodine. So my guess is that the problem in whatever part of the body that need to recognizes Iodine is that there is too much Chlorine. Also Chlorine is more similar to Iodine.
gamedori 7y ago
When I see a headline like this my instinct is to jump to "overfitting". In a study like this they use P=0.05 as their cut off for significance. One in 20 such studies would be expected to give meaningless results. But they had the choice of cohort (all kids or boys and girls separately), so 1 in 10. They measured urine concentrations of fluorine at three time points during pregnancy, which makes for 7 different potential combinations of input variables, for a total of 14 different potential analyses, where 1 in 20 is expected to be significant. Of course, they didn't preregister, so who knows whether their analysis changed on the fly..
- dtech 7y ago
  Good points. It's even more than 1 in 20 when you realize that studies does no get published with p > 0.05, so in the "published studies" sample this effect should be even larger.
o_p 7y ago
Is IQ even a significant measure? What a drop of 1.3 points in average even means. There is a measurable, real difference between a 120 and a 121.3 IQ person? This smells p-hacking
- olliej 7y ago
  No. It has been demonstrated on numerous occasions that all IQ tests are ineffective in predicting long term outcomes along any measure. It’s also been demonstrated in numerous studies that IQ tests are not remotely objective - cultural and other variations produce massive gaps in measured IQ of individuals in different social groups. To the extent that you can engineer IQ tests “without bias” that demonstrate group A is smarter than group B, for almost any groups A and B. That’s before we get into the borderline statistics, weak methodology, and vanishingly small sample size: 600 infants, so somewhere in the realm of 300/300 split, so they’re saying a p=0.05 result of a 1.3 point drop in IQ. You only need a minor number of infants with learning difficulties to cause that. Even if the testing methodology were sound (which it isn’t). Addendum: Per [1] the prevalence of learning disabilities is 7.8% of the population of 3-17 year olds, with 3.8% showing severe learning impairment. So if we take our 600 infants we’d expect around 40 kids with learning difficulties to some extent. But it should be easy to see that at the relatively tiny sample sizes (generously 150 boys in the F vs non-F groups) that minor variance would be more than sufficient to skew things. Further sample considerations: controlling for all those variables necessarily increases the noise (legit not sure how they get to p=0.05) due to the further reduced group sizes. [1] https://www.ncbi.nlm.nih.gov/books/NBK332880/ https://www.ncbi.nlm.nih.gov/books/NBK332880/
_1 7y ago
Did this come from the John Birch Society?
williesleg 7y ago
That and soybeans are the pussification of the western world. Thanks George seros.
gus_massa 7y ago
From the research article: > A 1-mg/L increase in MUFSG was associated with a 4.49-point lower IQ score (95% CI, −8.38 to −0.60) in boys, > but there was no statistically significant association with IQ scores in girls (B = 2.40; 95% CI, −2.53 to 7.33). > A 1-mg higher daily intake of fluoride among pregnant women was associated with a 3.66 lower IQ score (95% CI, −7.16 to −0.14) in boys and girls. I'm not sure about the notation, but even the first result looks pretty close to include the null hypothesis, where the change is 0.
cpr 7y ago
Here's an interesting aspect to the source of flouride of which most people are unaware: https://origins.osu.edu/article/toxic-treatment-fluorides-transformation-industrial-waste-public-health-miracle https://origins.osu.edu/article/toxic-treatment-fluorides-tr...
- efirman 7y ago
  Here is the CDC take on the products used in fluoridation. https://www.cdc.gov/fluoridation/engineering/wfadditives.htm#sources https://www.cdc.gov/fluoridation/engineering/wfadditives.htm... They are all subject to NSF Standard 60 requirements for purity. "Some have suggested that pharmaceutical grade fluoride additives should be used for water fluoridation. Pharmaceutical grading standards used in formulating prescription drugs are not appropriate for water fluoridation additives. If applied, those standards could actually exceed the amount of impurities allowed by AWWA and NSF/ANSI in drinking water."
DidISayTooMuch 7y ago
The conspiracy theorists were right?

88 points by tshannon 7y ago

It's interesting how policies like fluoridation of water are accepted at face value assuming the highest of scientific / statistical rigor was used to justify them. Of course that is not the case. Yet it requires just that, not common sense, to even question the practice in a manner that people will not consider somehow off-kilter. Our faith in authorities is stronger than ever, while the scientific community struggles with our basic ability to reproduce much of the research we even today cite is rigorous even ground-breaking.

geggam 7y ago
Interesting you get downvoted for stating we should question everything to include authority. Thought science was all about questioning and reconfirming truth as more knowledge is obtained
- lootsauce 7y ago
  I think that we are in for a new renaissance of scientific discovery as we grapple with all of the issues related to the reproducibility crisis. It will lead to better statistics, better science and more useful results. Untill then we will have people arguing with the authority of their position and "because science"
  - wysifnwyg 7y ago
    If you took a look at the study and the margin of error for their results, you'd notice that the margin of error has an overwhelming overlap.

not_a_cop75 7y ago

Old news.

mgamache 7y ago
People have suspected for a while, but it was not as clear as this new larger study. This is much more difficult to dismiss.
- wysifnwyg 7y ago
  If the math was solid, you'd have a point. But it doesn't, so you don't.
  - mgamache 7y ago
    Because you know more then the editors at Jama? Without explaining why?
    - wysifnwyg 7y ago
      Returning to the math, I did the calculations and here is the margin of error for each group: 11%, 9%, 9%. Their common error (the overlapping region of area) is the interval 87.79-104.95. The IQ scores from each group (94.91, 96.29, 96.47) are well within that margin of error. If you perform a t-test on 3-Ca vs. 3-placibo you'll see that the difference is not statistically significant.
- not_a_cop75 7y ago
  I'm sorry but if you've done even the most minimal study of fluoride levels, this is something you'd know - not because it's proven but because the extrapolated data going back from decades makes sense. To the point - the movie Doctor Strangelove even goes as far as to mock this controversy. So, I restate my claim. If you know nothing of this, then it's because you haven't researched it.
  - mgamache 7y ago

crooked-v 7y ago

This will definitely need further testing to confirm validity and to pin down the effect further, but if true, that will leave the question of whether as a society we feel the substantial dental health benefits in most areas are worth the 1.3-point IQ reduction, and if not, what we can do to counterbalance the effects of removing flouride from the water. Edit: Corrected the IQ drop amount.

dtech 7y ago
The average IQ drop was 1.3 points. It's 4.5 points per mg/L of fluoride and the average difference was 0.29 mg/L.
deleted 7y ago
[deleted]

krustyburger 7y ago

“Despite that, several researchers argue that the paper’s methodological shortcomings undercut its importance. In a statement to the Science Media Centre in London, an independent organization that sources expert opinions on science in the news, psychologist Thom Baguley of Nottingham Trent University in the United Kingdom noted the data “are very noisy,” meaning they contain a lot of other factors that could easily lead to false positives. Psychologist Stuart Ritchie at King’s College London added that the findings are just barely statistically significant, calling them “pretty weak and borderline.” By itself, the study “shouldn’t move the needle much at all on the question of the safety of fluoride,” he wrote.”

internet_user 7y ago
Safe treatment? Great. How about obtaining informed consent first?
- wysifnwyg 7y ago
  If you don't like how a water treatment plant operates, you could always dig your own well or purchase a water filter to remove the fluoride.
  - tomhoward 7y ago
    The suggestion to "dig your own well" suggests your comment is not entirely in good faith, but I'll respond as if it is. Plenty of people do filter fluoride from their tap water or source non-fluoridated water for drinking. The problem is that the mainstream population is led to believe that one has to be stupid to think fluoride might carry any health risks, and therefore stupid to take steps to reduce/avoid fluoride. As someone who was raised in mainstream society by educated, scientifically-minded people, and educated/interested in science myself, I held this assumption, right up until I was given very real cause to question it. Several years ago I started experiencing a complex combination of physiological impairments, including fatigue, memory/cognition problems, mood issues (depression/anxiety), digestion problems, immune-system dysfunction, among others. After much research and testing, my thyroid function has been identified as a key factor in my illness. Research on this topic has led me to multiple studies indicating that fluoride ingestion is linked to thyroid impairment. A recent study [1], published in Scientific Reports, affirms that hypothesis, but there are many others. (Incidentally, thyroid function has been linked to IQ [2][3], so this phenomenon could well be linked to the results of the study under discussion in this thread.) I'm currently undertaking a process to seek to remove accumulated fluoride from my body and raise my iodine level (of which fluoride is an antagonist, but which is an essential nutrient for thyroid function). Time will tell if this held to bring about the desired result. But the thing is, people who aggressively and reflexively dismiss any doubts about the safety of fluoride aren't interested in seeking and dispassionately examining studies like these, which suggests their motives are far more ideological than they are scientific. Meanwhile, countless people suffer with undiagnosed or “incurable” thyroid disorders and related conditions like chronic fatigue syndrome, and are made to believe they should “just try harder” or “stop pretending to be sick”. [1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5805681/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5805681/ [2] https://www.ncbi.nlm.nih.gov/pubmed/29757392 https://www.ncbi.nlm.nih.gov/pubmed/29757392 [3] https://www.endocrine-abstracts.org/ea/0020/ea0020p115 https://www.endocrine-abstracts.org/ea/0020/ea0020p115

jonny_eh 7y ago

> Longtime fluoridation critics are lauding the study, but other researchers say it suffers from numerous flaws that undercut its credibility. Either way, “It’s a potential bombshell,” … Umm, what?

awinder 7y ago
What, you missed Jack Ripper's celebratory tweetstorm?
- OrangeMango 7y ago
  Did he suggest that women drink only pure-grain alcohol during pregnancy?

word-reader 7y ago

I predict this research will receive reasoned and appropriate appraisal by the press and public officials.

THansenite 7y ago
Or, ya know, the real experts.....parents on Facebook.
- jackhack 7y ago
  Well, you can do what you like but when it comes to complex medical issues my winning strategy is to wait for a Hollywood actor, famous musician, or a daytime TV host to tell me what to think.

narrator 7y ago

Drinking fluoridated water does not do anything to protect teeth. They don't have it in Europe and have dental health that's just fine. Just goes to show you can do ANYTHING with good PR. The Fluoridation campaign was headed up by Edward Bernays[1] who was Freud's Nephew and one of the greatest propagandists of all time. His other famous accomplishment was convincing women that they should smoke[2]. [1] https://en.wikipedia.org/wiki/Public_relations_campaigns_of_Edward_Bernays#Water_Fluoridation https://en.wikipedia.org/wiki/Public_relations_campaigns_of_... [2] https://en.wikipedia.org/wiki/Public_relations_campaigns_of_Edward_Bernays#Cigarettes https://en.wikipedia.org/wiki/Public_relations_campaigns_of_...

dkersten 7y ago
I'm no fan of mass medication without a choice (or supplementation, whatever), but what you state is not the full story: > They don't have it in Europe and have dental health that's just fine. Much of Europe (not all) doesn't fluoridate their water, but they DO fluoridate salt and milk, or have high levels of natural fluoride in their water. To quote wikipedia[1] (yes, yes, I know, although they at least have a citation[2] for it): > the European Commission finds no advantage to water fluoridation compared with topical use > Community water fluoridation is rare in Continental Europe with 97–98% choosing not to fluoridate drinking water. Fluoridated salt and milk is promoted in some European countries instead. Water fluoridation has been replaced by other modes in many countries where water supplies are too decentralized for it to be a practical choice, or existing natural fluoride levels were already ample, including Germany, Finland, Japan, Netherlands, Sweden, Switzerland, Denmark and at a time Israel. That doesn't mean they didn't find fluoridation useful, just that topical use is just as good. Personally, I dislike the idea of forcing everyone to use fluoridated products (by not providing alternatives, or by putting it in all the water) and would prefer if topical use were encouraged instead, but my preferences aside, fluoride has been proven to be beneficial to teeth. [1] https://en.wikipedia.org/wiki/Fluoridation_by_country https://en.wikipedia.org/wiki/Fluoridation_by_country [2] https://en.wikipedia.org/wiki/Fluoridation_by_country#cite_note-EU2011-16 https://en.wikipedia.org/wiki/Fluoridation_by_country#cite_n...
- lootsauce 7y ago

dtech 7y ago

Here's the meat: > About 40% of the nearly 600 women lived in cities with fluoridated drinking water [...]. Three to 4 years after the women gave birth, researchers gave their children an age-appropriate IQ test. After controlling for variables such as parental education level, birth weight, prenatal alcohol consumption, and household income, as well as exposure to environmental toxicants such as lead, mercury, and arsenic, they found that if a mother’s urinary fluoride levels increased by 1 milligram per liter, her son’s (but not her daughter’s) IQ score dropped by about 4.5 points. That effect is on par with the other recent studies looking at childhood IQ and low-level lead exposure. So that's an average 1.3 IQ drop in cities with fluoride. For 1 gender. In an IQ test for 4 year olds. An IQ test. Can anyone with more knowledge of statistics chime in? This feels like it cannot be statistically significant with n=600, a subgroup analysis and a test I cannot imagine being even remotely accurate (IQ test for 4 year olds)

DevX101 7y ago
Until another replicated study comes along to dispute this, I'll take the word of the author and the editors at JAMA over your 'feel' that this isn't statistically significant. "There was a significant interaction (P = .02) between child sex and MUFSG (6.89; 95% CI, 0.96-12.82) indicating a differential association between boys and girls. A 1-mg/L increase in MUFSG was associated with a 4.49-point lower IQ score (95% CI, −8.38 to −0.60) in boys, but there was no statistically significant association with IQ scores in girls (B = 2.40; 95% CI, −2.53 to 7.33)." 1. https://jamanetwork.com/journals/jamapediatrics/fullarticle/2748634 https://jamanetwork.com/journals/jamapediatrics/fullarticle/...
- dtech 7y ago
  I browsed the article and have a basic understanding of statistics, no need to get patronizing. The article does not state the variance of this IQ test and does not state how many subgroups they analyzed and whether they corrected for that or if they a-priory were planning on analyzing gender. Picking subgroups until you've found one that is statistically significant is a well known technique in P-hacking. Other problems: - The IQ score for girls is 5 points higher on average than for boys in the study group - Fluoridation has the opposite effect for girls, the average IQ was 1.5 points higher. It is really strange for a chemical to have a completely different effect on young girls and boys. Statistical variance is much more likely - The average IQ score in the sample was 107, well above the average 100 - Parent IQ was not a variable, only the very roughly correlated high school diploma or not and household income. "Extraordinary claim require extraordinary evidence", and this study seems to at best be an indication that further research is needed rather than iron-clad proof of this effect.

hedvig 7y ago

Does it set a cap in potential or just drop in each individual relatively?

notadoc 7y ago

Original study without the opinionated article: https://jamanetwork.com/journals/jamapediatrics/fullarticle/2748634?guestAccessKey=d027f743-0a06-4f92-ad75-807f8b8d2a5e https://jamanetwork.com/journals/jamapediatrics/fullarticle/... Going forward, it'd probably be appropriate to only post the studies and not some sleazy clickbait opinion headline "you won't believe what this controversial study says blah blah!"

wysifnwyg 7y ago

Is it just me or do the groups have a significant overlap in their margin of error?

wysifnwyg 7y ago
Returning to this, I did the calculations and here is the margin of error for each group: 11%, 9%, 9%. Their common error (the overlapping region of area) is the interval 87.79-104.95. The IQ scores from each group (94.91, 96.29, 96.47) are well within that margin of error. If you perform a t-test on 3-Ca vs. 3-placibo you'll see that the difference is not statistically significant. How is this study concluding these results? What math are they using?

milin 7y ago

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4418502/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4418502/ This article from 2014 classifies fluoride as a neurotoxicant.

geggam 7y ago
Why is a link to peer reviewed material getting downvoted ? Not liking the study is one thing but downvoting a link to material without stating a reason is willful ignorance.
- not_a_cop75 7y ago
  It's absolutely dangerous in large quantities, like most anything else is dangerous in large quantities.
  - geggam 7y ago
    I am not a scientist and anyone who is should feel free but from what I have read flouride is a bioaccumlator. At what point does it become dangerous to continue to drink water ?
    - yarrel 7y ago
      Drowning is a strong contraindicator. There is also water intoxication, which can be deadly.
      - geggam 7y ago
        From flouride was assumed... humor noted ;)
    - Sohcahtoa82 7y ago
      > At what point does it become dangerous to continue to drink water ? According to this page [0], the LD50 of water is 6 liters, so somewhere before that. [0] https://www.compoundchem.com/2014/07/27/lethaldoses/ https://www.compoundchem.com/2014/07/27/lethaldoses/

aaomidi 7y ago

I'm not against fluoridation, but it does seem weird that we're so certain about these things...until we're not. Shouldn't we stop doing one-size-fits-all medication and actually expand access to toothpaste & dentists?

OedipusRex 7y ago
There are drugs that help with specific complications that are just simply not made because the market for them is too small, they're call orphan drugs (https://en.wikipedia.org/wiki/Orphan_drug https://en.wikipedia.org/wiki/Orphan_drug). The drugs that make it to market are not necessarily the best at treating you, they just cover enough of the population (normally more than one ailment per drug) and can be profitable.
- aaomidi 7y ago
  I understand these. And it pains me that they exist. I'm mostly talking about the availability of certain medication. Like, it makes sense to have a nationwide vaccine program. It doesn't make sense to have fluoridated water due to the relative ease of access to toothpaste. Especially because we really can't tell with certainty what consuming this does in the long-multigenerational term. Why should we take the risk?
  - OedipusRex 7y ago
    In my youth I lived off a well and did not have access to fluoridated water. My parents still live in that house. There are large swaths of people who live off of a well in the United States. We started adding fluoride to water because our knowledge at the time said it was a good idea (and still probably is). The rates of tooth decay falls when fluoride is introduced in drinking water. https://www.cdc.gov/fluoridation/pdf/natures_way.pdf https://www.cdc.gov/fluoridation/pdf/natures_way.pdf But the only places that have fluoride added to the water are metropolitan areas (at least around me in a Midwestern state).
    - lootsauce 7y ago

phkahler 7y ago

If this turns out to be true, I hope they'll take a closer look at the relationship between Fluorine and Iodine. My guess is the fluorine has effects that mimic iodine deficiency and perhaps increasing iodine can counter the negative effects of the fluorine. Women also need more Iodine than men, though I'm not sure if that's true at age 4 but it might explain the sex difference as well.

gus_massa 7y ago
It's a nice idea, but I think it's wrong. The nice part is that Fluorine and Iodine are in the same column of the periodic table, so they are somewhat similar. The problems is that between Fluorine and Iodine there is Chlorine and Bromine. Let's ignore Bromine for simplicity. The recommended intake of Fluorine and Iodine is approximately .001 or .002 g/day, and the recommended intake of Chlorine is 1 or 2 g/day. (With a lot of simplifications. For a serious number ask your medical doctor.) So the intake of Chlorine is almost 1000 bigger than the intake of Fluorine and Iodine. So my guess is that the problem in whatever part of the body that need to recognizes Iodine is that there is too much Chlorine. Also Chlorine is more similar to Iodine.

gamedori 7y ago

When I see a headline like this my instinct is to jump to "overfitting". In a study like this they use P=0.05 as their cut off for significance. One in 20 such studies would be expected to give meaningless results. But they had the choice of cohort (all kids or boys and girls separately), so 1 in 10. They measured urine concentrations of fluorine at three time points during pregnancy, which makes for 7 different potential combinations of input variables, for a total of 14 different potential analyses, where 1 in 20 is expected to be significant. Of course, they didn't preregister, so who knows whether their analysis changed on the fly..

dtech 7y ago
Good points. It's even more than 1 in 20 when you realize that studies does no get published with p > 0.05, so in the "published studies" sample this effect should be even larger.

o_p 7y ago

Is IQ even a significant measure? What a drop of 1.3 points in average even means. There is a measurable, real difference between a 120 and a 121.3 IQ person? This smells p-hacking

olliej 7y ago
No. It has been demonstrated on numerous occasions that all IQ tests are ineffective in predicting long term outcomes along any measure. It’s also been demonstrated in numerous studies that IQ tests are not remotely objective - cultural and other variations produce massive gaps in measured IQ of individuals in different social groups. To the extent that you can engineer IQ tests “without bias” that demonstrate group A is smarter than group B, for almost any groups A and B. That’s before we get into the borderline statistics, weak methodology, and vanishingly small sample size: 600 infants, so somewhere in the realm of 300/300 split, so they’re saying a p=0.05 result of a 1.3 point drop in IQ. You only need a minor number of infants with learning difficulties to cause that. Even if the testing methodology were sound (which it isn’t). Addendum: Per [1] the prevalence of learning disabilities is 7.8% of the population of 3-17 year olds, with 3.8% showing severe learning impairment. So if we take our 600 infants we’d expect around 40 kids with learning difficulties to some extent. But it should be easy to see that at the relatively tiny sample sizes (generously 150 boys in the F vs non-F groups) that minor variance would be more than sufficient to skew things. Further sample considerations: controlling for all those variables necessarily increases the noise (legit not sure how they get to p=0.05) due to the further reduced group sizes. [1] https://www.ncbi.nlm.nih.gov/books/NBK332880/ https://www.ncbi.nlm.nih.gov/books/NBK332880/

_1 7y ago

Did this come from the John Birch Society?

williesleg 7y ago

That and soybeans are the pussification of the western world. Thanks George seros.

gus_massa 7y ago

From the research article: > A 1-mg/L increase in MUFSG was associated with a 4.49-point lower IQ score (95% CI, −8.38 to −0.60) in boys, > but there was no statistically significant association with IQ scores in girls (B = 2.40; 95% CI, −2.53 to 7.33). > A 1-mg higher daily intake of fluoride among pregnant women was associated with a 3.66 lower IQ score (95% CI, −7.16 to −0.14) in boys and girls. I'm not sure about the notation, but even the first result looks pretty close to include the null hypothesis, where the change is 0.

cpr 7y ago

Here's an interesting aspect to the source of flouride of which most people are unaware: https://origins.osu.edu/article/toxic-treatment-fluorides-transformation-industrial-waste-public-health-miracle https://origins.osu.edu/article/toxic-treatment-fluorides-tr...

efirman 7y ago
Here is the CDC take on the products used in fluoridation. https://www.cdc.gov/fluoridation/engineering/wfadditives.htm#sources https://www.cdc.gov/fluoridation/engineering/wfadditives.htm... They are all subject to NSF Standard 60 requirements for purity. "Some have suggested that pharmaceutical grade fluoride additives should be used for water fluoridation. Pharmaceutical grading standards used in formulating prescription drugs are not appropriate for water fluoridation additives. If applied, those standards could actually exceed the amount of impurities allowed by AWWA and NSF/ANSI in drinking water."

DidISayTooMuch 7y ago

The conspiracy theorists were right?