Lithium in Drinking Water May Reduce Dementia
New research suggests that higher trace levels of lithium in drinking water can reduce dementia rates in the general population. In a 2017 article in the Archives of General Psychiatry, researcher Lars Kessing and colleagues compared data on 73,731 patients in Denmark with a diagnosis of dementia to 733,653 control participants without this diagnosis between the years 1970 and 2013. They were able to match the data to recorded levels of trace lithium in the drinking water in participants’ municipalities of residence.
Lithium levels in the water ranged from 0.6 micrograms per liter to 30.7 micrograms per liter in 151 different locations throughout Denmark. Compared to those exposed to 2.0 to 5.0 micrograms of lithium per liter of water, those exposed to more than 15.0 micrograms per liter had a lower incidence rate of dementia. However, those exposed to 5.1 to 10.0 micrograms per liter had a higher incidence of dementia. The same relationship was also found between lithium exposure levels and both Alzheimer’s disease and vascular dementia.
The lithium levels in the water were approximately 10,000 to 300 times lower than typical clinical doses (typically 900–1500mg/day, which produce concentrations ranging from 0.6 to 1.2 meq/L in patients’ blood). The minute exposures to lithium in the drinking water occurred over decades in the Danish study, and suggest that there may be long-term positive effects to chronic lifetime exposure to very low lithium levels.
These data follow others regarding exposure to trace lithium. In 2011, researcher Orestes V. Forlenza and colleagues reported in the British Journal of Psychiatry that low dose lithium (150–600mg/day) over a period of one year decreased the progression of mild cognitive impairment compared to placebo, while researcher Marielza Andrade Nunes and colleagues reported in the journal Current Alzheimer’s Research in 2013 that an even smaller dose (0.3mg/day) over a period of 15 months slowed the progression of Alzheimer’s dementia. Thus, low or microscopic doses consumed over long periods could slow cognitive deterioration.
