Tap water in the UK is anything but pure H2O.
Depending on where you live, many substances are added to make it cleaner, clearer and supposedly better for you.
With Scottish researchers investigating whether lithium should be added to the water to boost mood, we look at what's being put in your water before it reaches your glass - and its impact on your health.
Should lithium be in the water supply?
Scientists in Scotland are looking into whether adding lithium to water supplies could help mental health. Lithium is prescribed as a mood-stabilising drug (a typical daily dose is 300 mg), mainly for bipolar disorder, and is thought to work by modifying certain chemicals in the brain.
But it occurs naturally in many water sources in Scotland, leaching out from volcanic rock at very low concentration (providing a daily dose of about 2 mg per two litres of water).
Now researchers at the University of Glasgow School of Medicine are investigating where there is a link between lithium in water and lower suicide rates - previous research in Austria and Japan suggests that people whose water supply naturally contains lithium are less likely to take their own lives.
Source - Daily Mail