In the UK we’re incredibly lucky that we have high-quality tap water throughout the country. Even if you use water softeners in Gerrards Cross, the overall quality of the water that comes out of your taps will be very good.

Of course, there have been debates before about whether adding things to our tap water is a good idea if it prevents health problems – just look at the continued discussions over the merits (or not) of adding fluoride to tap water.

But now scientists from the University of Copenhagen have suggested that adding lithium to our water supplies could be one way of preventing dementia cases from developing.

In a study that spanned almost half the population of Denmark, the researchers found that those who had higher levels of lithium in their tap water were 17 per cent less likely to develop dementia than their counterparts in areas where lithium levels in water were lower.

They have suggested that further research is conducted to ensure that the higher lithium levels are the reason why these people saw a drop in their risk of developing dementia.

Professor emeritus of pharmacology at the University of Oxford David Smith told Net Doctor that it’s important to approach the results with caution, adding that at this stage we wouldn’t know what level of lithium salts should be added to tap water.

The UK Dementia Institute points out that the UK faces a “huge challenge” when it comes to tackling dementia and finding a treatment for the various conditions that sit underneath this banner. According to the organisation, 850,000 people in the UK currently suffer from dementia.