Why American Communities Began Adding Fluoride to Water

"Colorado Springs in the early 1900s, where residents with brown-stained teeth, later linked to high fluoride levels, also had lower rates of tooth decay." 

"first major trial of water fluoridation to a community water supply began in 1945 in Grand Rapids, Michigan, where dental exams soon confirmed that children who drank fluoridated water from birth had significantly fewer cavities." 

"for every dollar spent, communities of 1,000 or more people save an estimated $20 in dental treatment costs...Water fluoridation has played a very important role in helping to reduce the prevalence of complete tooth loss from 50 percent to close to 10 percent today."

"concerns have been around neurotoxicity and cognitive problems affecting children—at levels more than twice the recommended level—could harm developing brains." https://www.history.com/articles/fluoride-water-teeth-health