Fluoride in drinking water does not harm children’s IQ
twin-cities.umn.edu
Fluoride is a naturally-occurring mineral that has been shown to strengthen teeth and reduce cavities.

Study.

The study, published in PNAS, examined Wisconsin state testing records, archival information about when Wisconsin cities began to fluoridate their water, and data from the Wisconsin Longitudinal Study, which has followed a random sample of 10,317 high school seniors from 1957 through 2026. Key findings include:

  • There is no evidence supporting a connection between community water fluoridation and children’s IQ.
  • There is also no evidence supporting a connection between community water fluoridation and cognitive functioning at various points later in life.
  • Findings confirm evidence published in previous research which also used a national sample, but considered school achievement test scores instead of actual IQ scores.
  • pelespirit@sh.itjust.works
    12·
    24 hours ago

    I’m going to post this again, because everyone needs to fucking understand that science is studying results and a process:

    What about autoimmune diseases and inflammation? It looks like there might be a link, but they haven’t studied it enough.

    Based on the body surface area of humans and animals, and considering the metabolism and absorption of fluoride in rats, according to calculations, the WHO’s safety threshold for fluoride intake from drinking water (1.5 mg/L) corresponds to a fluoride concentration of 10 mg/L in the drinking water of rats. After 1 week of acclimatization, the 150 rats were randomly assigned to 5 groups (n = 30) and provided with drinking water containing 0, 10, 25, 50, or 100 mg/L of fluoride. Although 50 and 100 mg/L are not equivalent to the doses humans are exposed to in natural environments, they are commonly used in animal models of fluorosis and have been widely demonstrated to be robust in rat models of fluorosis [35,36,37]. According to the exposure mode and time of fluoride, it can be divided into three modes: fluoride treatment for 12 weeks (12 w), fluoride treatment for 24 weeks (24 w), and fluoride treatment for 12 weeks and 12 weeks of improve water(12 w12 wi) (Table S1). Rats were euthanized with isoflurane anesthesia at the end of the breeding period.

    https://www.mdpi.com/2305-6304/13/2/95

    • village604@adultswim.fanEnglish
      24·
      21 hours ago

      “We gave rats 6.66 times more than humans are exposed to and bad stuff happened.”

      That’s really not a good methodology.

      • htrayl@lemmy.world
        6·
        17 hours ago

        I mean, its fine - but it just isn’t overly meaningful for how we make decisions as individuals. But to design a scenario where we would absolutely see an effect is valuable to see if we should invest more money into larger studies.

    • sbird@sopuli.xyzEnglish
      9·
      18 hours ago

      copying my answer from a different comment relating to fluoride:

      Fluoride in the water is the opposite of bad, it’s good for your teeth. It’s in toothpaste for a reason! There is no reasonable evidence that fluoride causes any major health problems, in fact, the fluoridation of water is dubbed as one of the largest public health accomplishments in a while. In addition, the fluoride added to water is miniscule, tiny, far far too low in concentration to be toxic. It also occurs in plenty of foods naturally too (fruits, seafood, spinach, etc.)

      Some more information of fluoride:

      https://my.clevelandclinic.org/health/treatments/11195-fluoride

      https://www.cdc.gov/oral-health/prevention/about-fluoride.html

      https://www.sciencedirect.com/science/article/abs/pii/S000291652334718X

      • CookieOfFortune@lemmy.world
        4·
        13 hours ago

        Eh the first major study in fluoride, the Grand Rapids study would never hold up to today’s standards. It was not a blind study and cavity detection is subjective.

        Also drinking water is a poor way to deliver fluoride. The mechanism of action requires physical contact with your teeth to work. Toothpaste and mouthwash would be a better option and reduce consumption. To my knowledge, there hasn’t been a modern large scale study conducted looking into different delivery methods. We do have some evidence comparing countries that don’t fluoridate but still have low cavity rates.

        And while rare, fluoride allergies do exist.

        It can also be difficult to dose.

        • sbird@sopuli.xyzEnglish
          4·
          13 hours ago

          the first major study in fluoride, the Grand Rapids study would never hold up to today’s standards. It was not a blind study and cavity detection is subjective.

          There has been many more studies on fluoride, none of which have shown that that the low concentrations of fluoride added to drinking water has any negative health effect. Not just the one, always check multiple sources!

          Also drinking water is a poor way to deliver fluoride

          It depends on the area you’re dealing with. In some countries, it’s more cost effective to put fluoride in the water supply, while in others, fluoride toothpastes are more effective. In Germany, they put fluoride in iodized salt!

          • CookieOfFortune@lemmy.world
            2·
            9 hours ago

            There has been many more studies on fluoride, none of which have shown that that the low concentrations of fluoride added to drinking water has any negative health effect.

            Again, there have not been any randomized control trials testing the efficacy of fluoride in drinking water compared to other delivery methods.

            It depends on the area you’re dealing with. In some countries, it’s more cost effective to put fluoride in the water supply, while in others, fluoride toothpastes are more effective. In Germany, they put fluoride in iodized salt!

            Did you just not read my comment? The reason isn’t cost, it’s not that expensive to add fluoride.

            The reason is we wouldn’t be adding anything to drinking water if there were better alternatives. If we started again with today’s standards, no scientist would recommend fluoridated drinking water.

            • sbird@sopuli.xyzEnglish
              3·
              9 hours ago

              The reason isn’t cost, it’s not that expensive to add fluoride.

              In many countries, particularly in developing nations, fluoridation of water is too expensive (since you need the infrastructure for it), and fluoride toothpastes are preferred instead. But in industrialised countries, where infrastructure for managing the water supply already exists, fluoridation of water is more effective. Places where tap water is more readily available (like the U.S., much of Western Europe, Canada, Ireland, etc.) will also be more likely to adopt the fluoridation of water.

              The reason is we wouldn’t be adding anything to drinking water if there were better alternatives. If we started again with today’s standards, no scientist would recommend fluoridated drinking water.

              Fluoridation of water still helps to prevent tooth decay, and in regions where it is cost-effective, it is a great benefit to public health! Of course, fluoride toothpastes are great, but it’s not the best solution for everywhere.