Invercargill's city council is on the verge of deciding whether or not to continue adding fluoride to their water supply.

Of the 400 submissions to the council's draft annual plan this year, 300 raised concerns about fluoridation, most of which were against the idea of adding it into the city's drinking water. Central Hawke's Bay stopped water fluoridation last year, New Plymouth and Taumarunui about a year before that, and Ashburton stopped adding fluoride to the water in 2006.The Hamilton City Council is holding a tribunal over water fluoridation and the South Taranaki District Council's decision to fluoridate water supplies is due to go under review in the near future.

According to Fluoride Action Network New Zealand, 23 of New Zealand's 67 councils have added fluoride to their water supplies, and since 2006, six areas in New Zealand had opted to stop adding fluoride to water supplies after residents raised the issue.

So what's the big deal? Why's fluoride on the way out? Check out our ten fluoride facts you should know.