Fluoridating our water supply is completely unnecessary and even harmful. It was meant to aid in preventing dental decay. However, any benefits that accrue from the use of fluoride come from the direct application of fluoride to the outside of teeth.
The National Research Council (NRC) states that drinking fluoridated water can cause dementia in adults and low IQ in children. It also creates thyroid problems, diminished bone strength, and bone cancer in males under 20 years old.
The American Dental Association has advised parents that fluoridated water should not be given to babies. This can cause dental fluorosis, a permanent tooth defect. Early life exposures may also damage the brain, causing learning deficits and other problems.
It is also hard and expensive to filter manually.