Quite a number of years ago in a particular area of the United States, it was found that natural fluoride in the ground was helpful with the teeth of children who lived there as they used water with the fluoride every day.
They had strong teeth with few if any fillings.
So the suggestion was that fluoride added to drinking water would be beneficial; however there was a catch. The naturally occurring fluoride was calcium fluoride; what is being foisted on the public is sodium fluoride which apparently is a byproduct of the aluminum industry. It is easy to see that calcium fluoride would be beneficial as calcium has always been associated with strong bone growth. Sodium is a different proposition.
On quite a different topic, when a Slovakian came to New Zealand, he stayed with our family for a couple of years and, when he bought a car, I fastened an arrow printed on cardboard and pointing to the left to the dash board. He never had any trouble with his driving.
However in an emergency, anyone who is used to driving on the right, could, in an emergency, automatically turn to the right, which is why, perhaps there are so many accidents when foreigners are driving.