Millions of Brits sent warning of increased risk of dementia

Scientists believe that 40% of the UK population could be at a greater risk of dementia because of lower mineral levels in their tap water.

The first-of-its-kind study suggests people who live in softer water areas – around 27million Britons – may be more susceptible to the degenerative disease because of low calcium and magnesium levels.

Scientists from Imperial College London and China have speculated that the minerals protect the brain and their absence could also have a corrosive effect on water pipes, increasing the risk of lead and other toxic elements entering the supply.

Research carried out by scientists on a data pool of nearly 400,000 UK residents showed that those living with soft water had structural brain differences in 20 different areas, making them more vulnerable to a host of neurodegenerative diseases including dementia and multiple sclerosis.

Soft water is defined as having between zero and 60mg of calcium per litre, while hard water has between 120 and 300mg per litre. Low calcium and magnesium in water supplies correlated with a 34% higher risk of developing vascular dementia compared with hard water areas, the study found.

Soft water naturally occurs when rainwater which hasn’t passed through limestone or other rocks displays low mineral content, a phenomenon that is most common in Devon, Cornwall, North Yorkshire, Cumbria and western parts of Wales.

Water softeners can also treat hard water by removing magnesium and calcium to prevent scale build up in pipes and combat dry skin – with thousands of homes in hard water areas including the south and east of England around London reliant on treatment systems.

Alongside the research, scientists from the Shanghai Jiao Tong University School of Medicine said the groundbreaking analysis of how water mineral content impacts neurodegenerative diseases “highlighted the importance of optimising water quality standards to ensure long-term health benefits”.

Dr Tom Russ, director of the Alzheimer Scotland Dementia Research Centre, said more work had to be done to understand the impact of people’s environment on their dementia risk but admitted that water “may potentially be a part of that”.

“There’s still a much bigger risk of dementia from other risk factors such as smoking, high cholesterol and high blood pressure and most people shouldn’t be too worried about the effect that tap water might have,” he told the Mail.

“If it has any effect, it’ll be very small.”

NHS data showed record numbers of dementia diagnoses in England last year, with 499,068 people confirmed to have the disease – a jump of 19,416 from the previous 12 months.

It was also the leading cause of death in the UK in 2023 according to Alzheimer’s Research UK, with 75,393 patients passing away after diagnosis.