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Should I try SLS-free toothpaste?

SLS-free toothpaste has become increasingly common on our supermarket shelves; but what is it, and should you be using it?

SLS-free Toothpaste is free from a chemical called Sodium Lauryl Sulfate (SLS), a powerful detergent commonly used in other cleaning agents we find in the home – shampoos, shower gels, and soaps.

In toothpaste, SLS kills microbes and reduces plaque, and it also helps make the toothpaste foamier, making it easier to spread around your mouth.

However, as Dr Chris van Tulleken discovered in an earlier Trust Me experiment, Sodium Lauryl Sulfate can irritate the skin, especially for people with sensitive skin, so could it be irritating our mouths too? Many of our viewers think so, and have written to us to say that SLS-free toothpaste helped to free their mouths from ulcers.

So is there anything to it?

The evidence

There have been a number of studies on ulcers and SLS in toothpaste, but the evidence is mixed. Some reported that people with mouth ulcers who used SLS-free toothpaste experienced a 70% reduction in ulcers. But other studies found no change.

In one trial, 90 people who regularly suffered from mouth ulcers were asked to try 8 weeks on a toothpaste with SLS, and 8 weeks on an SLS-free toothpaste. The trial was ‘double-blind’, so neither the participants nor the researchers knew who was using which toothpaste. The researchers found that the SLS free toothpaste did not reduce the number of ulcers or the frequency with which people got them.

However, they did find that while using the SLS-free toothpaste, the volunteers self-reported feeling less pain and that the ulcers healed slightly quicker.

So, if you get ulcers, it might just be worth trying an SLS-free toothpaste – they’re a bit less foamy, but they might work for you.