Researchers have discovered that naturally occurring lithium in the brain is depleted early in Alzheimer’s disease, especially in the prefrontal cortex, and that restoring physiological levels with lithium orotate in mice can prevent brain damage and memory loss.

A few limited clinical trials of lithium for Alzheimer’s disease have shown some efficacy, but the lithium compounds they used — such as the clinical standard, lithium carbonate — can be toxic to aging people at the high doses normally used in the clinic.