3 ms·

> the lower level, 0.7 mg/L, which is about half the levels with the decent evidence of harm. Do you have a source for this claim? This summary of a meta-anal

> the lower level, 0.7 mg/L, which is about half the levels with the decent evidence of harm. Do you have a source for this claim? This summary of a meta-analysis[1] says that there was only very weak evidence for measurable IQ harm in the range 8-16 mg/L, which is 10-20 times the recommended level. The highest quality studies in the meta-analysis showed no relationship at all between fluoride exposure and IQ[2]. [1] https://sciencebasedmedicine.org/fluoride-and-iq/ https://sciencebasedmedicine.org/fluoride-and-iq/ [2] https://pubmed.ncbi.nlm.nih.gov/36639015/ https://pubmed.ncbi.nlm.nih.gov/36639015/

gojomo 2y ago
https://www.theguardian.com/society/article/2024/aug/23/fluoride-water-study https://www.theguardian.com/society/article/2024/aug/23/fluo... > The long-awaited report released this week comes from the National Toxicology Program, part of the Department of Health and Human Services (HHS). It summarizes a review of studies, conducted in Canada, China, India, Iran, Pakistan and Mexico, and concludes that drinking water containing more than 1.5 milligrams of fluoride per liter is consistently associated with lower IQs in kids. >The report did not try to quantify exactly how many IQ points might be lost at different levels of fluoride exposure. But some of the studies reviewed in the report suggested IQ was two to five points lower in children who had had higher exposures. >Since 2015, federal health officials have recommended a fluoridation level of 0.7 milligrams per liter of water, and for five decades before the recommended upper range was 1.2. The World Health Organization has set a safe limit for fluoride in drinking water of 1.5.
- coldpie 2y ago
  Thank you! Here's a link to the root source: https://ntp.niehs.nih.gov/whatwestudy/assessments/noncancer/completed/fluoride https://ntp.niehs.nih.gov/whatwestudy/assessments/noncancer/... I wish the summary there had more detailed numbers. It's hard to understand the level of conflict between this source & mine.
woodruffw 2y ago
Good summary. This is a good example of people making bijective errors around public health: the presence of a "safe level" does not itself imply that levels above it are unsafe; all it does is express confidence that the level itself is safe.

gojomo 2y ago

https://www.theguardian.com/society/article/2024/aug/23/fluoride-water-study https://www.theguardian.com/society/article/2024/aug/23/fluo... > The long-awaited report released this week comes from the National Toxicology Program, part of the Department of Health and Human Services (HHS). It summarizes a review of studies, conducted in Canada, China, India, Iran, Pakistan and Mexico, and concludes that drinking water containing more than 1.5 milligrams of fluoride per liter is consistently associated with lower IQs in kids. >The report did not try to quantify exactly how many IQ points might be lost at different levels of fluoride exposure. But some of the studies reviewed in the report suggested IQ was two to five points lower in children who had had higher exposures. >Since 2015, federal health officials have recommended a fluoridation level of 0.7 milligrams per liter of water, and for five decades before the recommended upper range was 1.2. The World Health Organization has set a safe limit for fluoride in drinking water of 1.5.

coldpie 2y ago
Thank you! Here's a link to the root source: https://ntp.niehs.nih.gov/whatwestudy/assessments/noncancer/completed/fluoride https://ntp.niehs.nih.gov/whatwestudy/assessments/noncancer/... I wish the summary there had more detailed numbers. It's hard to understand the level of conflict between this source & mine.

woodruffw 2y ago

Good summary. This is a good example of people making bijective errors around public health: the presence of a "safe level" does not itself imply that levels above it are unsafe; all it does is express confidence that the level itself is safe.