Why water fluoridation isn’t as scary as it sounds

I grew up in Napier, brushed my teeth with fluoride toothpaste twice a day, and had an OK diet. I still got tooth decay. I wish I’d grown up in an area with fluoridated water.

A recent proposal on the touchy topic of water fluoridation would see Director-General of Health Dr Ashley Bloomfield make the decision for all of New Zealand, rather than local councils.

I know water fluoridation is a super polarising subject to talk about. It’s like bringing up vaccinations around people you don’t know very well. I’d like to explain why I don’t see water fluoridation as something bad or scary.

First, let’s look at what water fluoridation actually means:

Fluoride is a mineral that is naturally present in ground water. Water fluoridation involves adjusting the fluoride in tap water to an optimal level of between 0.7 and 1.0 ppm (parts per million) with the purpose of preventing tooth decay. To put this number in context, most toothpastes, including SOLID toothpaste and toothpaste tablets, contain 1000ppm fluoride. Water fluoridation at this low level causes a 25% reduction in tooth decay in both adults and kids, without any obvious negative health effects.

And now let’s look at how fluoride works to prevent tooth decay:

Tooth decay occurs when plaque acids break down the tooth structure. Fluoride makes teeth more resistant to this acid.

Tooth enamel is predominantly made of a substance called hydroxyapatite. When fluoride (from toothpaste, or drinking water) is present in the mouth in the right conditions, it is pulled into the tooth structure, and forms fluorapatite

Fluorapatite is more resistant to plaque acid breakdown than hydroxyapatite.

OK, great, but I already eat a low sugar diet, brush my teeth twice a day with fluoride toothpaste, and lucked out in the genetic lottery with teeth that aren’t susceptible to decay – why do I need fluoride in my water?

Well, you may not. Your teeth would most likely still be fine without water fluoridation. It’s not going to do you any harm, but it’s also probably not a necessity.

But what about your neighbours, or your kid’s schoolmates, or people who have to choose buying food over buying toothpaste?

Water fluoridation has been around for a long time (since 1945) and has been extensively studied. I view water fluoridation as a way of safely strengthening teeth over a community. Of course, its more necessary for some people than others. But hey, if it means that significantly less Kiwi kids need fillings or extractions, I see that as a good thing for us all.

Let me know what you think, and if you’d like me to do more posts on fluoride, or any other oral health topic ☺