Can a Simple Mineral Protect Against Alzheimer’s?

Lithium is a naturally occurring mineral found in trace amounts in many foods and drinking water. In medicine, lithium salts—especially lithium carbonate—have been used for decades as mood stabilizers for bipolar disorder and treatments for certain headache disorders.

Now, emerging research suggests this simple mineral might play a role in brain health and Alzheimer's prevention.

The lithium-Alzheimer’s connection

Several lines of evidence point to lithium's potential protective effects against cognitive decline and Alzheimer’s disease (AD), the world’s most common form of dementia.

A groundbreaking new brain study

In August, Nature published an elegant study. Researchers analyzed 27 trace metals in the brains and blood of older adults—some with normal cognition, others with Alzheimer's or mild cognitive impairment (MCI), an early phase of memory loss that often progresses to AD. The researchers found lithium was the only metal significantly reduced in the brains of people with MCI and Alzheimer’s.

The researchers then turned to mice. When they depleted lithium from the animals’ diets, the results were striking. The mice developed accelerated Alzheimer's pathology, including:

• Amyloid-β plaques and tau tangles (hallmarks of AD)
• Brain inflammation from activated microglia cells
• Loss of neural connections (synapses and axons)
• Cognitive decline and memory loss

Interestingly, supplementing with a form of lithium called lithium orotate protected against all these changes. Remarkably, when given to aged mice without AD pathology, lithium restored their memory to levels seen in young adult mice.

The mechanism? Lithium appears to inhibit an enzyme called GSK-3β, which is elevated in both lithium-deficient mice and humans with Alzheimer’s. This enzyme contributes to plaque formation, tangles, neuroinflammation, and oxidative stress—all core features of AD.

Population studies offer intriguing clues

Research examining trace lithium levels in drinking water has found associations between higher natural lithium exposure and lower dementia rates. While these population studies can't prove cause and effect, they support the idea that even low lithium doses might offer neuroprotective benefits.

Human trials show mixed but promising results

Small clinical studies have tested lithium carbonate (150-600 mg daily) in older adults with MCI or Alzheimer's. While individual trial results varied, a meta-analysis of three placebo-controlled trials (199 patients total) found lithium significantly slowed cognitive decline compared to placebo, with no major differences in side effects. These results should be considered suggestive, very preliminary, and neither conclusive nor confirmatory.

In one two-year study of 61 patients, 16% of those taking lithium progressed from MCI to dementia, compared to 30% on placebo—though this difference didn't reach statistical significance. The lithium group performed better on three of seven cognitive tests, but improvements were modest.

Why we’re not there yet

Despite these intriguing findings, significant limitations remain:

• The associations between lithium in water and reduced dementia are correlational. Lifestyle, genetics, and environmental factors could influence results.
• Existing trials involve limited participants and haven't run long enough to conclusively demonstrate Alzheimer's prevention. Notably, no human trials using lithium orotate (the form showing promise in mice) have been published.
• Results in animals, while compelling, don't necessarily replicate in humans. The leap from mouse to human neurobiology requires rigorous validation.
• Even at low doses, lithium can affect kidney and thyroid function, and the long-term safety of microdosing remains uncertain.

Finally, lithium isn’t approved by any major health authority for preventing or treating Alzheimer’s. Current clinical guidelines don’t yet support its use for cognitive protection.

The bottom line

The findings from recent studies are genuinely noteworthy and open a promising new research path—but it’s still early days. Human clinical trials—especially using potentially more effective forms like lithium orotate at lower and possibly safer doses—are essential before any medical recommendations can be made. The next critical step is well-controlled human studies that can definitively answer whether lithium supplementation could help prevent or slow Alzheimer’s disease.

Until then, while lithium shows exciting promise in lab and animal studies, it’s not ready for primetime. For now, this remains a fascinating area of research to watch—but not yet one to act on.

— Dr. David Dodick