Higher lithium levels in drinking water linked to lower risk of dementia
Researchers in Denmark studied 800,000 people and found that people who drink water with higher levels of lithium, which is natural found in tap water, appear to have a lower risk of developing dementia.
Although the findings are not clear-cut, it showed that the highest levels of lithium cut risk and moderate levels were worse than low ones.
Experts said it was an intriguing and encouraging study that hinted at a way of preventing the disease.
The study, at the University of Copenhagen, looked at the medical records of 73,731 Danish people with dementia and 733,653 without the disease.
Tap water was then tested in 151 areas of the country.
The results showed moderate lithium levels (between 5.1 and 10 micrograms per liter) increased the risk of dementia by 22% compared with low levels (below 5 micrograms per liter).
However, those who drank water with the highest lithium levels (above 15 micrograms per liter) had a 17% reduction in risk.
According to the researchers, this is the first study they are aware of that investigated the association between lithium in drinking water and the incidence of dementia.
“Higher long-term lithium exposure from drinking water may be associated with a lower incidence of dementia,” they said.
Lithium is known to have an effect on the brain and is used as a treatment in bipolar disorder.Experiments have shown the element alters a wide range of biological processes in the brain.
However, the lithium in tap water is at much lower levels than is used medicinally.
This broad impact could explain the mixed pattern thrown up by the different doses, as only certain dosing sweet-spots change brain activity in a beneficial way.
Prof. Simon Lovestone, from the department of psychiatry at the University of Oxford, said the study is “really intriguing”.
“In neurons in a dish and in mouse and fruit-fly models of Alzheimer’s disease, lithium has been shown to be protective. Not only that, but lithium is used to treat people with bipolar disorder and some studies have suggested that people on lithium for this reason, often for life, might also be protected from Alzheimer’s,” he noted.
He said there should now be studies to see if regular, small doses of lithium could prevent the onset of dementia.
At the moment, there is no drug that can stop, reverse or even slow the progression of the disease.
