What the Science Says About Fluoride in Our Water

How much do we need to protect our teeth without risking possible cognitive harm?

- SUMATHI REDDY

Few of us have spent a lot of time thinking about fluoride-until recently. Now it has become a lightning rod of controversy.

Public-health officials are sparring over conflicting studies weighing the benefits and risks of fluoride, especially for young children. Most everyone agrees it is important for our dental health. The question is how much fluoride we need to protect our teeth without risking possible cognitive harm.

Recent analyses suggest some evidence that high levels of fluoride might harm the brains of children and developing fetuses. Other studies have found no such evidence. And there is no indication that fluoride hurts adult cognition.

The fluoride mineral is part of the Earth's crust. It exists in all water and in many foods. In much of the country, extra fluoride gets added to public drinking water. It is also in toothpaste and other dental products.

The decision to add fluoride to drinking water is made by local municipalities. Nearly 20 communities across the U.S. have halted the practice, with more discussing it. Many European countries including France and Germany don't fluoridate drinking water.

You can find the level of fluoride for some communities on the Centers for Disease Control and Prevention website.

Fluoride's benefits

Most U.S. public-health experts and doctors staunchly support adding fluoride to public drinking water to mitigate tooth decay.

Cavities are typically caused by acid that breaks down the enamel of the teeth. Fluoride helps remineralize those areas, making them more resistant to decay.