A science podcast I was listening to recently went over the pros and cons, interviewing serious scientists and public health officials, and it made me think about this.
I had previously written off concerns about fluoride as the province of crackpots like the general in Dr Strangelove, but it is genuinely an issue of pros and cons and weighing harms and benefits. It is not like vitamin D supplementation in milk. Vitamin D is an essential nutrient, but fluoride is not a nutrient at all in the way we typically mean that (a substance that is used for biological processes in the body). Obviously, you can cause harms if vitamin D levels get too high, but insuffiency is vastly more common.
Fluoride most definitely protects against cavities and improved dental health is one of the biggest advances in quality of life in human history. In WWI, the US army required that soldiers had at least 6 opposing teeth (i.e. 3 up and 3 down) and something around 10-15% (400,000 total) candidates could not meet that standard (so they had lost most of their teeth by, say, age 20).
In an era of generally poor dental care, putting fluoride in the water was a solution that turned out to be effective (along with all sorts of other dental health measures). As there continues to be poor dental care in a lot of poor communities, removing fluoride falls on them disproportionately.
But then there is plenty of evidence that fluoride is toxic at fairly low levels.
Then that comes down to a question of whether or not you should put it in the water, which is not obvious one way or the other.
The big plus is that everyone gets it, regardless of whether or not their parents are taking them to a dentist and making them brush their teeth.
The big minus is that everyone gets it, but some of those people drink 4X as much water as others, which means they are getting 4X the fluoride, which means that some people might be at dose too low to be effective while others are past a safe dose.
So the article says...
QuoteThe calculations showed a so-called benchmark level of about 0.3 mg/L, which suggests that water-fluoride concentrations at many locations may not be safe. In the United States and Canada, fluoride is often added to community drinking water at a concentration of 0.7 mg/L with the intention of protecting against caries.
The problem is that the number of mg/L is not important - it is mg/day that matters. So someone drinking 3X the avg amount of water (say, someone who plays/works out in the heat a lot) would not be getting 2.3X the benchmark level as suggested by the concentrations above, but actually 7X the benchmark level.
As a "close to home" way this plays out, my dad has been on a well for the last 30 years. He never had an issue with cavities for his first 65 years, but in the last 30 years he has and he has taken to using a high-concentration fluoride toothpaste.
Anyway, after all that, I decided that my middle ground is probably fine for me - no fluoride in my water, but I use fluoridated tooth paste.
More generally, my feeling is that if kids saw a dentist
at least 2X per year, you could be much more targeted and give fluoride treatment only to people who need it. That would be ideal. But I worry that poor kids, who already fall through the cracks on dental health, will fall further and that might have a larger effect on overall life outcomes than fluoridating water and the second best solution is to have pregnant and lactating avoid fluoridated water.
Again, this is a case where you're balancing risks in both directions and the risks are different for different populations. It requires a nuanced approach and voters HATE nuance.