It's hard for someone of a certain age (that would be me) to see news city council in St. John, N.B., had voted narrowly to stop adding fluoride to the drinking water and not think of Dr. Strangelove.

Stanley Kubrick's 1964 classic black comedy about nuclear annihilation hinges on a paranoid air force general's fear of what fluoridation of water could do to his "precious bodily fluids."

The idea that fluoridation, aimed at reducing cavities in children's teeth, which began in the 1950s, was some dark Communist plot to undermine American society was meant to be viewed as ridiculous.

But 50 years later, the debate over fluoridation remains just as hot, if not quite as loony. St. John is just the latest Canadian city to opt out.

[ Related: Dental impact of no fluoridation in Calgary's water studied ]

St. John councillors voted 6-5 Monday evening (with Mayor Mel Norton breaking a tie) to stop adding fluoride to the city water supply, apparently for budgetary reasons, CBC News reported.

"The business case for the way fluoride is delivered in this city is an epic fail," said Coun. Ray Strowbridge.

According to a city staff report last year, the fluoride program cost $177,000 last year but residents were only consuming one per cent of the chemical, which inhibits bacterial activity on teeth.

There's plenty of scientific evidence that fluoridated water has helped reduce rates of tooth decay, which can affect overall health. Cities in Canada and the U.S. began adding it to water supplies in the 1940s.

As this LiveScience page notes, very low levels of added fluoride are considered safe. But some believe exposure to higher levels – through drinking lots of water and and via the fluoride found in almost all toothpaste – can be linked to health problems, including lower IQs in children, thyroid issues and a rare kind of childhood bone cancer.

The Canadian Cancer Society noted studies on rats that point to a bone-cancer risk involving levels of fluoride up to 200 times the recommended amount.

The most common problem with excess fluoride levels is fluorosis, which can cause teeth to be stained brown and to crack or pit. But most of the concern is with levels many times higher than the trace amounts put into drinking water.

Still, the anti-fluoridation movement has been persistent, and lately fairly successful at pushing its perspective via groups such as the Fluoride Action Network.

Dozens of Canadian municipalities have opted out of fluoridation in recent years, according to this Postmedia News article last year. Vancouver apparently stopped adding it in the early 1960s, Quebec City removed it in 2008, Calgary in 2011 and Windsor, Ont., in April 2013, among many others.

[ Related: B.C. won't force measles vaccination amid outbreak ]

According to Maclean's post last April, only 32 per cent of the Canadian population has access to fluoridated water, down from 43 per cent in 2005.

"In many ways the rise of the grassroots anti-fluoride movement is similar to the anti-vaccine lobby, which has campaigned hard against the practice of vaccinating children on the grounds it causes autism," Manisha Krishnan wrote in the Maclean's post.

"Those opposed to fluoride are equally organized and determined, driven by the belief that the medical establishment is ignoring recent research."

A mistrust of science lies at the heart of both fights.

It's probably true that ingesting way too much fluoride could be detrimental, just like almost anything else. But the benefits of minute amounts seem to far outweigh the risks.

Still, there's evidence Strangelove's Gen. Jack D. Ripper may win after all.