5 surprising toothpaste facts you need to know

Can whitening toothpastes really whiten your teeth? What does remineralising actually mean? Is there anything to watch out for with 'eco' or natural toothpastes?

We've interrogated the facts behind the big marketing claims made by toothpaste brands, enlisting the help of a panel of dental experts to get to the bottom of what the evidence is behind the bold statements on the box.

We found that many common marketing phrases are based on the inclusion of fluoride, which can be found in even the cheapest toothpastes, and that with some claims you really need to read the small print.

These are the toothpaste facts you need to know.

Choosing the best toothpaste - we reveal which common toothpaste ingredients for whitening, enamel repair and sensitivity really work

1. Whitening toothpaste won't actually 'whiten' your teeth

Or, at least, not in the way you might expect it to.

Whitening toothpastes can help to remove surface stains caused by things such as smoking or drinking coffee, which can help your teeth look whiter, but none will change the underlying colour of your teeth.

Your teeth can be stained in two different ways: intrinsic staining happens inside your teeth and can be caused by trauma, certain medical treatment or excessive childhood fluoride consumption (but this is rare in the UK). Teeth can also yellow as you age.

The only way to lighten this intrinsic colour is through bleaching and the only way to achieve this effectively is through dentist-adminstered professional products (using hydrogen peroxide).

Whitening toothpastes tackle extrinsic staining, which is basically surface discolouration.

This type of staining is typically caused by things such as smoking or drinking tea, coffee and red wine. Toothpastes that make whitening claims are essentially stain-removing, not whitening.

Find out which whitening ingredients to look for and whether you really need to spend big on premium whitening pastes, in our guide to choosing the best toothpaste.

2. Fluoride is the foundation of many toothpaste claims

Fluoride is the key ingredient to look for in your toothpaste. It infiltrates the enamel's surface and reaches areas that brushing can't - providing you brush for around two minutes - leading to less tooth decay.

It makes the tooth surface harder (known as remineralising) and more resistant to attack by sugar-loving bacteria.

Claims around preventing cavities are generally based on the inclusion of fluoride, as are some about repairing or remineralising enamel.

There are a couple of different types of fluoride. Stannous fluoride also effectively combats sensitivity for some sufferers and has antibacterial properties, so claims to relieve tooth sensitivity and prevent gum disease may also be based on fluoride.

This is why (despite some pricier toothpastes having extra ingredients that can have an effect), even the cheapest fluoride toothpaste is an effective way to keep your teeth healthy.

3. You probably aren't getting the fluoride you need from your water supply

Some people may assume that they don't need fluoride in their toothpaste because they're getting it from the tap water supply.

The British Fluoridation Society (BFS) says past research has found that 40% of people believe they receive fluoridated water.

But in reality, only around 10% of the UK population receives water with optimal levels of fluoride.

To find out if your area is one of them, visit the BFS website or contact your local water supplier.

4. Natural toothpastes may be missing this vital ingredient

Natural, eco-friendly and vegan toothpastes (or chewable tablets) are on the rise, often accompanied by a high price. But these products don't always contain fluoride, and that's not always immediately obvious from the packaging.

Mechanically brushing with a fluoride-free paste will clean teeth and remove plaque, but it won't help with reaching the areas of teeth where brushing doesn't reach, and you increase your risk of developing dental cavities even if you also follow a low-sugar diet. Fluoride remains the most evidence-backed way to maintain your dental health.

There are products that give you the best of both, though. Colgate's 'Smile for Good' paste has recyclable packaging and a vegan-friendly formula, and Kingfisher has fennel and mint toothpastes containing fluoride, alongside their fluoride-free offerings.

Other eco or natural brands may well contain fluoride (the ideal amount is between 1,350 to 1,500 parts per million/ppm), but check the ingredients carefully before you buy.

5. Don't assume a trendy ingredient has scientific evidence to back it up

Charcoal has enjoyed a real surge in popularity in recent years as a whitening ingredient in toothpaste, but whether this is deserved is another matter.

It certainly looks dramatic when you've got a mouthful of black foam and this might make you think your teeth look whiter after brushing, but Dr Nigel Carter, chief executive of the Oral Health Foundation, says there is currently no robust evidence to support the claims made by many of these products in terms of tooth whitening.

In fact, as many are also fluoride-free, he says: 'Some products may actually be harmful as they don't contain fluoride and so put consumers at an increased risk of tooth decay.'

He also warns that some of the products may be overly abrasive and, if used too often, could wear away tooth enamel.

So, don't get bamboozled by the eye-catching marketing - if you're on a budget, just find a simple fluoride toothpaste and pay attention to your brushing technique.

For more information on enamel repair, sensitivity and whitening ingredients that are worth looking out for, see our guide to choosing the best toothpaste.

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