Fluoride:

U.S. lowers recommended amount in drinking water.

— The government is lowering the recommended amount of fluoride in drinking water because some kids are getting too much, causing white splotches on their teeth.

It’s the first change since the government urged cities to add fluoride to water supplies to prevent tooth dec ay more than 50 years ago. Now, fluoride is put in toothpaste, mouthwash and other products as well.

One study found about 2 out of 5 adolescents had tooth streaking or spottiness. It’s primarily a cosmetic issue, said Deputy Surgeon General Boris Lushniak, in announcing the new standard Monday.

The mineral fluoride is in water and soil. About 70 years ago, scientists discovered that people whose drinking water naturally had more fluoride also had fewer cavities.

Grand Rapids, Michigan, became the world’s first city to add fluoride to its drinking water in 1945. Si x years later, a study found a dramatic decline in tooth decay among children there, and the U.S. surgeon general endorsed water fluoridation.

Today, about 75 percent of Americans get flu- oridated water.

But adding fluoride was — and has remained — controversial. Opponents argue its heal th effects aren’t completely understood and that adding it amounts to an unwanted medication.

Among the more recent dust-ups: Portland, Oregon, voters rejected a proposal to add fluoride two years ago. Sheridan, Wyoming, this year resumed adding fluori de ; the city stopped in 1953 after a referendum.

Water fluoridation has been a public health succe s s, and communities should keep adding fluoride, said Kathleen O’Loughlin, the American Dental Association’s executive director, who joined Lushniak in Monday’s announcement.