Could Lithium Hold the Key to Alzheimer’s? New Research Raises Hopes

In a striking breakthrough nearly ten years in the making, scientists from Harvard Medical School have uncovered new evidence that lithium, long used to treat mood disorders, may be essential to brain health and play a protective role against Alzheimer’s disease and age-related cognitive decline.

For decades, lithium has been known primarily as a mood stabilizer, used in treating bipolar disorder and depression. But new findings, published in Nature, reveal that the element is not just a drug, it’s a trace nutrient naturally present in the body, similar to iron or vitamin C, and may be critical to maintaining a healthy brain.

In experiments involving mice, researchers found that when dietary lithium was removed, the animals developed signs of inflammation and accelerated brain aging. In genetically modified mice bred to develop Alzheimer’s-like pathology, low lithium levels triggered faster accumulation of harmful beta amyloid proteins, hallmarks of the disease, and hastened memory loss.

But there was good news too: “Maintaining normal lithium levels protected the mice from Alzheimer’s-like changes,” said Dr. Bruce Yankner, professor of genetics at Harvard Medical School and the study’s lead author.

“Compelling evidence”

Dr. Ashley Bush, director of the Melbourne Dementia Research Center in Australia, praised the study in a Nature editorial, writing that it offers “compelling evidence that lithium does in fact have a physiological role and that normal aging might impair the regulation of lithium levels in the brain.”

The research points to a mechanism whereby beta amyloid plaques bind to lithium, even the small amounts naturally found in the body, depleting the mineral and disrupting the function of microglia, the brain’s waste-clearing cells. This creates a cascade: as more beta amyloid accumulates, it soaks up more lithium, reducing the brain’s ability to clear harmful proteins.

“It is a potential candidate for a common mechanism leading to the multisystem degeneration of the brain that precedes dementia,” Yankner explained. “The data are very intriguing.”

A new formulation shows promise

To counter the lithium-binding effect of beta amyloid, researchers tested various lithium compounds. One form, lithium orotate, did not attach to amyloid plaques and showed remarkable effects. In mice showing signs of Alzheimer’s, the compound reversed memory decline and reduced brain plaque accumulation.

“Mice treated with lithium were once again able to navigate mazes and identify new objects,” the study notes. Those given a placebo showed no improvement.

Important caution: Don’t self-medicate

Despite the promising results, Yankner emphasized caution. “A mouse is not a human,” he said. “Nobody should take anything based just on mouse studies.”

Although the lithium levels used in the research were about 1,000 times lower than therapeutic doses for mood disorders, the element can be toxic at higher levels, causing thyroid or kidney issues in some patients. Tests on the mice showed no such side effects, but human trials are needed to assess safety and proper dosage.

Yankner confirmed that he and his team do not hold financial interests in the research. The study was primarily funded by the National Institutes of Health, along with private grants.

Prior studies point in same direction

Previous epidemiological studies support the new findings. A 2017 Danish study revealed that areas with higher lithium concentrations in drinking water had lower dementia rates. A 2022 UK study found people prescribed lithium were about half as likely to be diagnosed with Alzheimer’s.

Still, Yankner believes lithium’s psychiatric use overshadowed its potential role in normal physiology. Until recently, the levels present in the body were too minuscule to measure, but new technology allowed his team to detect and analyze lithium in brain tissue.

In samples from brain banks at Rush University, Massachusetts General Hospital, Duke, and Washington University, scientists consistently found lower lithium levels in patients with Alzheimer’s or early memory decline. “At first, frankly, we were skeptical,” said Yankner. “But it held up.”

What causes lithium to drop?

The researchers suspect a drop in brain lithium may be tied to aging-related decreases in absorption from the blood, influenced by diet, genetics, and environmental factors. Foods rich in lithium include leafy greens, legumes, nuts, and spices like turmeric and cumin. Some mineral waters also contain higher levels of the element.

In other words, many foods already linked to better brain health may owe part of their protective effect to lithium.

As Yankner put it: “Oftentimes one finds in science that things may have an effect, and you think you know exactly why but then subsequently turn out to be completely wrong about why.”

For now, the scientific community is watching closely as this once-overlooked element potentially opens the door to a new era in Alzheimer’s research and treatment.