The United States government is recommending that less fluoride be put in drinking water.

After four years of debate, the government believes that there needs to be less fluoride in drinking water because it can cause streaking in children’s teeth. The reason for the streaking is that more products now include the mineral, causing people to get an overdose of it, reports Fox News.

The US government now recommends that all areas include 0.7 milligrams of fluoride per liter of water. Previous recommendations had this level for warmer climates, but cooler areas were recommended 1.2 milligrams of the mineral er liter of water. Fluoride was first added to water in 1945 in Grand Rapids, Michigan, Fox News notes.

“While additional sources of fluoride are more widely used than they were in 1962, the need for community water fluoridation still continues,” Dr. Boris Lushniak, the Deputy Surgeon General Rear Admiral, told Newsweek. “Community water fluoridation continues to reduce tooth decay in children and adults beyond that provided by using only toothpaste and other fluoride-containing products.”

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