More than 50 years after issuing its previous guideline, the government on Monday recommended that drinking water contain .7 milligrams of fluoride per liter. It was the first change in the recommendation since the previous level -- a range of .7 to 1.2 milligrams per liter -- was set in 1962.

The Department of Health and Human Services said the new recommendation reflects the fact that Americans now have other sources of fluoride -- including toothpaste, mouth rinses and sealants -- than they did when fluoride was first added to drinking water in 1945 to combat tooth decay. Now, according to this post, fluoride is added to about 70 percent of municipal water supplies.

If you're of a certain age, as I am, you can remember when some communities fought water fluoridation, er, tooth and nail, viewing it as a communist plot (you'll also probably recall this scene from the Stanley Kubrick film "Dr. Strangelove."). But the Centers for Disease Control and Prevention has called water fluoridation one of the 10 great public health achievements of the 20th century.

Today, as Mother Jones points out here, anti-fluoride activists are mostly scientists and environmentalists who believe we're ingesting too much. The federal Public Health Service agreed, but only on one small point -- that the added fluoride was causing a cosmetic problem, white markings or spots on some people's teeth from fluorosis.

In fact, a thorough review of the science of fluoridation that began back in 2006 has shown no other health effects from small amounts in the water supply, Deputy Surgeon General Boris D. Lushniak said in an interview Monday.

"Fluoride saves people's teeth," Lushniak said unequivocally. Since its introduction, it has helped reduce the prevalence of tooth decay (i.e. cavities) in teenagers from more than 90 percent to about 60 percent, he said.

The new recommendation stems from the belief that fluoride levels needed to be reviewed after 53 years without changes, he said. "Anything in public health keeps moving," Lushniak said. "The landscape of fluoride has changed in these 53 years."