Fluoride is a mineral that naturally occurs in nature. It naturally gets incorporated into many foods and water. Dentistry discovered the benefits of fluoride when a dentist in Colorado found that many of his young patients had brown stained teeth, but no cavities. Research was done and found that the local water which these children drank naturally had 14 part per million (ppm) of fluoride. Further research showed that brown staining dramatically increased in concentrations above 7 ppm, but that resistance to decay was excellent in a concentration of 1 ppm with no staining. A major study was conducted in 1945 when Grand Rapids, Michigan became the first city to add fluoride to it’s drinking water. The control city for the study was Muskegon, Michigan which had the same water source for it’s drinking water; namely, Lake Michigan. Muskegon did not receive fluoridation.
The reduction in decay was so dramatic within the years in Grand Rapids, compared to Muskegon, that Muskegon stopped being the control city; and started adding fluoride to it’s water as well.