Is Water Fluoridation Safe?

There have been more than 50 studies showing an association between higher fluoride exposure and lower IQ, but is it cause-and-effect?

This is the third video in a five-part series on water fluoridation. The first two were Why Is There Fluoride in Water? Is It Effective? ( ) and Side Effects of Water Fluoridation: Dental Fluorosis ( ).

The next video is Why I Changed My Mind on Water Fluoridation ( ), and the series will wrap up with Medicine’s Response to the Changing Science on Fluoride Safety ( ).

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Thanks for watching. I hope you’ll join in the evidence-based nutrition revolution!
-Michael Greger, MD FACLM

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Dave McKinnon

  • @qow2427 says:


  • @dumpfbrumsel4687 says:

    Finally we are about to enter the real interesting areas on adverse effects from water fluoridation.

  • @LauLol says:

    Respect to you doctor. “conspiracy theorists” were right again.

    • @grexzen says:

      Keep telling yourself that if it makes you feel better.

    • @LauLol says:

      @@grexzen drink more if it makes you feel better.

    • @joshw9558 says:

      @@grexzen okay so if you’re going to post a comment like that you need to back it up… Prove the conspiracy theorists wrong. We will be waiting for your reply

    • @tamcon72 says:

      @@joshw9558 The conspiracy theorists are rarely right because they go too far. Like, there’s evidence that fluoridation can have harm x, y, or z, but the Tin Foil Hat Brigade does not accept this and always goes for broke with claims that it will make you sprout an extra head overnight.

    • @dominicmutzhas6002 says:

      Well actually, it really depends.
      Here where I live conspiracy theorists, said you shouldn’t use fluoride toothpaste…and delivered no scientific evidence.

      Their Argumentation was that the people are deliberately being kept sheep, not that the current practice might be dangerous because of lacking evidence of safety.

  • @LaurentLenquette says:


  • @wildgeese5707 says:

    With modern dentistry being what it is, a better question is WHY do we continue to artificially add it into the water supply when we don’t really need it. A dentist can prescribe fluoride rinses for kids with hypo plastic teeth if they are worried about it. Why risk it when there’s even a chance it’s not good for you?

    • @Mr.N0.0ne says:

      Unfortunately the people who have put themselves in the position of making health related decisions for us are not fit for the role.

      Those who can afford it, can purchase bottled spring water and run it through a filter before consumption.

  • @ch33psk8 says:

    Wow, only thirty years too late. Cutting edge Mike!

  • @shivashakti4261 says:

    dumbing down of america conspiracy theorists doesn’t sound so cucko coo anymore huh?

  • @allencrider says:

    That’s why we have MAGA voters.

  • @thebrinksf69 says:


  • @sandiegoryu says:

    The comments section for this video is so weird. Did anyone watch the video???

  • @NutritionFactsOrg says:

    What are the Side Effects of Water Fluoridation: Dental Fluorosis, check out the video:

  • @justinhale5693 says:

    Fluoride in ground water could be buffered by calcium which would understate the harms. Calcium impairs fluoride absorption.

  • @pdblouin says:

    This is just evidence for children. I didn’t choose what to drink as a child, so my IQ has been set, presumably? Hopefully the next video presents evidence for adult health outcomes.

  • @velatoget says:

    I don’t care if it’s good or bad for my teeth. I don’t want the government medicating me. If I want to drink fluoride, let me go out and buy some to drink.

  • @veg0machine says:

    So that’s why people still voted for Biden.

  • @mchagawa1615 says:

    Thank you <3

  • @veganchiefwarrior6444 says:

    No idea what he just said, i stopped drinking tap water at like 22 years old maybe it was too late lol

  • @-Kerstin says:

    “Why I changed my mind” indicates that at some point in time, past or present, Greger had the opinion that water flouridation wasn’t a completely idiotic thing to do. That’s depressing.

    • @bradman3001 says:

      How is that depressing? Changing your mind based on scientific evidence is something everyone should be proud of.

  • @user-rx1om7rs3b says:

    I’ll never understand this super short format with cliffhangers. What’s the point?

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