Lithium is being touted as an overlooked micronutrient, and dietary supplements containing very low doses of it are being promoted for everything from improving mood and countering cognitive decline to preventing violent behavior and prolonging lives.
Lithium is a chemical element present in soil, rocks, and groundwater. Traces are found in many foods. But lithium is not considered an “essential” nutrient-that is, humans don’t need to consume it to stay healthy.
In high doses, lithium is a psychiatric drug typically prescribed to treat bipolar disorder or as an adjunct treatment for certain people who don’t respond to antidepressants. While prescription doses are usually 300 to 1,800 milligrams of lithium carbonate a day, of which about 20 percent is elemental lithium, most supplements provide a tiny fraction of that (0.3 to 10 milligrams of elemental lithium, usually in the form of lithium orotate).
Some animal studies have linked low-level lithium consumption to health benefits, as have some human observational studies that looked at lithium intake, usually from water. For instance, a study in JAMA Psychiatry in 2017 found that Danes whose tap water had the highest levels of lithium were at reduced risk for dementia, though water with mid-range levels was linked to elevated risk, which the researchers could not explain.
But overall the observational research has produced inconsistent findings. For instance, some studies have suggested benefits from higher lithium intake from tap water only in men, some only in women; some found no apparent benefits at all. There have been few published clinical trials on low-dose lithium supplements, none demonstrating benefits. One exception was a sketchy Brazilian study in Current Alzheimer Research in 2013, which suggested that a “microdose” of lithium helped prevent further cognitive decline in people with Alzheimer’s, compared to a placebo.
High doses of lithium, as provided by medication, can have serious adverse effects, including hypothyroidism, convulsions, and kidney disease. Little is known about the safety of long-term use of low-dose lithium supplements.
Bottom line: There’s no reason to take lithium as a dietary supplement.