Fluoride – Why the controversy?

Fluoride often comes as sodium fluoride, and is a mineral salt much like table salt. The key difference is that when it is applied to the surfaces of the teeth (such as when you use fluoridated tooth paste) or when it is consumed by drinking fluoridated water, it hardens the teeth against being dissolved by acids. Tooth decay happens because acids produced by bacteria (i.e. plaque) dissolve the tooth and allow a cavity to form.

Fluoride has been known about for a long time, it was noted in American frontier towns in the 1850-1900 period that some towns had little dental decay and some had a lot. Eventually the cause was discovered – some towns had more fluoride in their drinking water! Fluoride’s use in preventing tooth decay is thought by the US Centres for Disease Control to be one of top-10 most important public health advances in human history, along with things like sanitation and vaccination.

In the UK most of our drinking water is not fluoridated. Some parts of the country have fluoride added to their water supply and some have a little fluoride in the water naturally. See this map if you want to know more.

So what is the controversy? There are groups of people who seek a “natural” solution to problems who feel fluoride might cause harm. Despite fluoride being a natural substance, that is naturally in the water in many parts of the UK.  No strong (or even reasonably strong) evidence exists to support this idea. I was horrified to visit YouTube and see hundreds of videos by people saying fluoride is terrible, its a government conspiracy etc and only a few by reputable organisations saying it is beneficial. Until I realised these hundreds are offering their opinion, and very little credible evidence. It was a powerful reminder, that just because a lot of people shout loudly (as they do on YouTube) it doesn’t mean they are right!

I will consider one strand of anti-fluoride thinking and that is that water fluoridation is giving medication without consent, but I reject this position. If you feel this way you can avoid fluoridated tap water by drinking mineral water (which might contain natural fluoride anyway, it is a mineral after all)  – do not deprive the least well off of the chance to have fewer fillings.

If we look at those who support using fluoride to protect your teeth they include:

  • US Centres for Disease Control
  • British Dental Association
  • American Dental Association
  • World Health Organisation
  • The NHS

The list of reputable organisations goes on and on. They use evidence to guide them not rumour/here-say/conspiracy theories.

I personally use fluoridated toothpaste as do most people, I also prescribe higher strength fluoride toothpaste for people at risk of tooth decay with spectacular results (many people I have treated have avoided multiple fillings due to timely introduction of increased fluoride, along with better diet and brushing). I would like our water supply to be fluoridated, which would bring the greatest benefit to the most deprived, who might not have good quality toothpaste available, or be using it very much at all.

As a conclusion I will summarise by saying that all of the good quality evidence (and there are thousands of studies to support this position) say that fluoride in the correct doses, by toothpaste and/or drinking water, is safe and effective at reducing between 20-50% of tooth decay.