For years, many communities have added fluoride to drinking water to help reduce cavities. But a new study that has found a link between fluoride levels in pregnant women and lower intelligence in their children may provide further ammunition for those who are calling that practice into question.

In the first study of its kind, investigators at the University of Toronto, McGill, the Harvard School of Public Health, and other institutions have found a link between fluoride in the urine of pregnant women and lower measures of intelligence in children.

Read more