The only practicing physician in the state legislature has asked hundreds of water districts to stop adding fluoride to drinking water, citing recommendations from the American Dental Association that moms avoid using tap water to mix baby formula.

State Rep. Joey Hensley, a Republican from Hohenwald, said he mailed about 250 letters last week after hearing that ingesting too much fluoride can cause fluorosis - or staining of the teeth - in young children.

"I'm just trying to bring it more to the front, because more and more people are concerned about it. They don't have a choice now," Hensley said.

Hensley added he was worried about low-income mothers who may have to mix baby formula with bottled water, which could be costly.

Water districts decide individually whether to add fluoride - long touted for its cavity-fighting properties - to its water, and Hensley said he doesn't plan to introduce legislation banning the practice.

Metro Water Services in Nashville adds fluoride to its water. (To see whether your water system adds fluoride, go HERE and click on the name of the county where you live.)

A statement by the dental association still recommends fluoridating water to prevent tooth decay.

Read more about the American Dental Association's recommendations.