Talking to the press, Robert F. Kennedy Jr. trampled on a still-sacred cow when he said, “We don’t need fluoride in our water.” It was not the first time Kennedy, whom President-elect Donald Trump has tapped to lead the Department of Health and Human Services, brought up the topic of water fluoridation.

In an earlier X (Twitter) post, when RFK Jr. mentioned water fluoridation in the same breath as “arthritis, bone fractures, bone cancer, IQ loss, neurodevelopmental disorders, and thyroid…