Researchers in Scotland are set to test whether areas with higher naturally occurring levels of lithium in drinking water supplies are associated with lower levels of suicide among the local population. 

The research follows several recent studies from different parts of the world which have appeared to identify an ‘anti-suicidal effect’ in water supplies with high levels of lithium, a naturally-occurring chemical which is the standard pharmaceutical treatment for bipolar disorder. 

‘We have a considerable body of evidence that suggests that high levels of the chemical in the water supply could save lives,’ Professor Allan Young, Professor of Mood Disorders at the Institute of Psychiatry, Kings College, London. 

Lithium remains the standard treatment for bipolar disorder because of its dual ability to reduce the symptoms of mania, including impulsive behaviour, as well as depression. As such, it’s most robust impact is in halving the risk of suicide in people with bipolar disorder. 

'The key to lithium’s impact on reducing suicide as a pharmaceutical agent is in reducing impulsivity as well as depression,’ Professor Young said, speaking at the Royal College of Psychiatrist's International Congress in London, this week. ‘We are now embarking on urgent research to establish the impact of taking low levels on lithium as medication, as well as adding lithium to the water supply in much the same way as fluoride is added to prevent tooth decay.’

So far two large studies in Texas and Japan, along with several smaller studies carried out between 1989 and 2013, have found that suicide rates are higher in areas where there are low levels of lithium in the drinking water. ‘If we can become deficient in calcium and zinc, there is absolutely no reason why we cannot become deficient in lithium,’ said Dr Daniel Smith, Reader of Mental Health at the Institute of Health & Wellbeing at the University of Glasgow. 

He is currently conducting a pilot study of lithium levels in Scotland, a country that offers a perfect opportunity to carry a low-cost full-scale study that will answer the question once and for all.

‘Previous studies have not always taken different variables such as poverty and unemployment into account when making this comparison,’ he said. ‘In Scotland, we have ideal conditions in which to carry out this research. A single organisation, Scottish Water is able to measure levels of lithium by postcode and we can make use of the excellent routine data which is available from sources such as the Scottish Health Survey and from the Information Services Division of NHS Scotland.’