I read in the news yesterday that the city of Moncton, New Brunswick (Canada, if you’re not familiar) is being urged to start fluoridation of its water supply now that five years have passed since it stopped doing so at the behest of a bunch of people who apparently have zero understanding of the words “scientific consensus” (exhibit A: the non-profit Canadians Opposed to Fluoride). According to the dentists in Moncton, the number of cases of dental cavities (aka caries or tooth decay) has risen since 2011, moreso among the city’s children.

People have opposed fluoridation of water supplies since it began, usually on the basis of the precautionary principle (“we don’t know for sure that it’s safe”) and of individual liberty (“it’s my right not to have it”). But in the decades and decades we’ve been doing this, we’ve had a lot of time to study it.