All you've shown is harmful effects from high levels of fluoride. If your water is high enough to cause a problem, then you have a very good reason to avoid it. I was just wondering why someone would want to avoid ALL fluoride.
I had another journal under post #22 which shows the harm under low levels of fluoride titled, "The relationships between low levels of urine fluoride on children’s intelligence, dental fluorosis in endemic fluorosis areas in Hulunbuir, Inner Mongolia, China.
That's a perfect example of what I mean. The levels they call "low" in drinking water are HIGHER than target levels for water fluoridation, but more importantly, if you look at their data (Fig 2) you see that IQ actually goes UP as urinary fluoride increases from 0.4 to 0.7 mg/l, then drops back down til about 1.2 mg/l, then goes back up at ~1.4, then drops back down. You could just as easily use this data to argue for the existence of an "optimal" amount of fluoride at ~0.7mg/l. Ecologic studies of this type are fraught with problems, and IQ is susceptible to modification by a huge number of factors that are very difficult to control for. Thus I wouldn't use this data to argue much of anything. It's certainly not 'conclusive'.
Where do you find that Fluoride is beneficial to health at all? The previous study I posted showed that Fluoride levels (at a level exactly the same as my water district in the United States) is harmful. Seems like you feel the need to hold onto your previous knowledge (ego protection?), even when presented conclusive evidense against it.
Agree. I haven't seen evidence that humans require any fluoride, period. There is no RDA for it. There are no fluoride deficiency syndromes or symptoms. Fluoride can occupy iodine receptors in the body, which unlike fluoride, we definitely need.
There are some studies showing dental benefit, but there is much contradictory data.
There's no RDA for Lithium, either, but it's included in the best multivitamins on the planet. There's no RDA for a lot of things that we need. There's about a century worth of data showing the importance of fluoride in the development of healthy dentition, and it has been shown to substantially improve bone strength in osteoporosis when properly dosed. Fluoride and Iodide are like night and day, chemically, so I really doubt that there is any evidence that fluoride can occupy iodide receptors in any significant way. I am open to evidence, of course. Any negative effect that could be shown is undoubtedly at high levels, which I'm not arguing for. Believe it or not, I care about my own health, and am looking for the right amount of fluoride to ingest. There is absolutely zero evidence that the optimal amount is... zero. I guess it's just my "ego protection" at work, but I'm trying to look at the real evidence about fluoride and make decisions about it based on reality rather than emotion. The existence of an anti-fluoride, anti-science cult that floods the net with misinformation makes it hard for all of us to do this.
Here are a couple of study abstracts indicating that fluoride and iodine levels are inversely correlated in humans:
1.
FLUORIDE, WATER HARDNESS, AND ENDEMIC GOITRE "The prevalence of goitre in 17 Himalayan villages has been estimated. Water-samples from each village were taken, and levels of iodine, fluoride, and hardness determined. In 13 villages wide
variations in goitre prevalence were not attributable to differences in iodine intake, which remained constant within a narrow range.
Instead, variations in goitre prevalence were found to correlate closely with the fluoride content (ρ=0·74; P<0·01) and with the hardness (ρ=0·77; P<0·01) of the water in each village. The effects of fluoride and water hardness seem to be independent."
2.
RESEARCH ON CORRELATION OF URINARY IODINE AND URINARY FLUORIDE"Through researching on iodine-deficiency patients who take iodine and healthy people who don't take iodine respectively in iodine-deficiency area,to analyze whether there is relative relationship between urinary iodine and urinary fluoride in urine.[Methods]Took 26 people with simple goiter or with cretinism as experimental group and 24 healthy people as control group,measured their urinary iodine and urinary fluoride.[Results]The average of urinary iodine of experimental group and control group was(126.5±25.8)μg/L and(87.1 ±27.1)μg/L,P﹤0.01 respectively,while the average of urinary fluoride was(0.37±0.11)mg/L and(0.57±0.13)mg/L respectively. The correlation coefficient of urinary iodine and urinary fluoride was r=-0.723.[Conclusions]The average level of urinary iodine of people with simple goiter or with cretinism who take iodine is higher than healthy people who don't take iodine,however,as for urinary fluoride,the average level of which of people with simple goiter or with cretinism taking iodine is lower than healthy people without taking iodine.
So it indicates that urinary iodine and urinary fluoride negatively correlate to each other. From this result,we conclude there is competition between urinary iodine and urinary fluoride when they are discharged in human."
