How Grand Rapids became the first city to fluoridate its water

Here’s a surprising “first”: in 1945, Grand Rapids became the first U.S. city — and, by most accounts, the first city in the world — to add fluoride to its drinking water. It was a big science experiment. Doctors had noticed that people in places with natural fluoride in their water had fewer cavities, so the city teamed up with the U.S. Public Health Service, the state health department, and the University of Michigan’s dental school to test the idea. Starting on January 25, 1945, Grand Rapids added a tiny, measured amount of fluoride to its water, while the nearby city of Muskegon went without it for comparison. They tracked the teeth of nearly 30,000 local schoolchildren. The result was dramatic: cavities in Grand Rapids kids dropped by more than 60%. The finding helped fluoridation spread to cities across the country, and decades later the CDC called community water fluoridation one of the ten great public-health achievements of the 1900s. Fluoride in tap water has been debated since the very beginning — and people still argue about it today — but it all started right here in Grand Rapids. There’s a historical marker downtown that tells the story.