OK, confession time: up until a few weeks ago I had no idea what fluoride was or how it worked to protect teeth against decay. I’d heard of it, vaguely assumed it was probably in the water I drink, but that was about as far as it went.

Then one day I posted on my Instagram stories about a chic and exciting new toothpaste I was going to try. It was blackcurrant flavour, and it looked really nice on my bathroom shelf, especially in comparison to my usual supermarket-bought tubes. But then I started getting replies from dentists who follow me. 

“Unless dentures will be chic and exciting in a few years I’d avoid like the plague” said one message. Another read: “Just a quick warning that by all means use this but also use a fluoridated toothpaste twice a day. Decay rate goes through the roof when people change to non-fluoride toothpaste because it’s the only defense against it.”

Was I an idiot for not realising just how important fluoride was? Probably. I did a poll (naturally) and it turns out the majority of those who answered (403 people out of 515) didn’t realise, either. Of course there were some people who knew, but I’m glad it turned out I really wasn’t alone.

So, after a quick lesson via my DMs – the main things that I learnt were that level of fluoride in toothpaste should ideally be 1450ppm (it’s listed on the back of tubes and is found in all the usual suspects like Colgate and Oral B), and once you’ve brushed your teeth spit the toothpaste out but don’t rinse with water or mouthwash, otherwise you wash away tiny particles of fluoride that work throughout the day – I decided to go back to basics and find out exactly what fluoride is, how it works and whether it is actually in my water.

What is fluoride?

“Fluoride is a naturally occurring mineral found in water. It can help prevent tooth decay, which is why it’s added to many brands of toothpaste and, in some areas, to the water supply through a process called fluoridation,” explains Dr Simon Chard, co-founder of Pärla.

Is there fluoride in UK water supplies?

“Around 5.8 million people in England receive fluoridated water. Areas where the schemes are in place include parts of the West Midlands, the North East, the East Midlands, Eastern England, the North West, Yorkshire and Humber,” says Dr Chard. “Birmingham was the first place to introduce a water fluroidation scheme in the UK in 1964.”

According to the NHS, some parts of the UK water supply naturally contains a level of fluoride similar to that found in the schemes, but your local supplier should be able to tell you how much is in it and whether more is added. It’s also found in some food and drink, like fish and tea.

How does fluoride work to protect teeth?

“It helps prevent tooth decay by slowing the breakdown of enamel and increasing the rate of the remineralization process,” says Dr Reena Wadia, dental expert, gum specialist and founder of RW Perio. “The new enamel crystals that form are harder, larger and more resistant to acid. Tooth enamel is hard yet porous, and plaque on the surface of teeth can produce acids that seep into the pores of the enamel and break down its internal structure. This process, called demineralisation, can create a weak spot in the tooth that may become a cavity if left untreated.”

Is it important to use a toothpaste with fluoride in it?

In short, yes. “I would not recommend toothpaste without fluoride. At the moment there is not an equivalent or alternative to fluoride,” says Dr Wadia. However, some people believe fluoride is bad for your health but studies haven’t found any evidence that fluoride added to water causes harmful side effects.

So, while those chic tubes might look just as good on your bathroom shelf as they do mine, it’s always best to have a ‘sensible’ option that you use more often than not. That’s not to say you can’t use toothpaste without fluoride, but just make sure you use something that does contain it as well. 

Main image: Getty