Study Reveals Lithium Deficiency Linked to Alzheimer’s Risk

BOSTON, Massachusetts — Researchers at Harvard Medical School have discovered a potential link between lithium deficiency in the brain and Alzheimer's disease, presenting new insights into how lithium could play a role in brain health and aging.

This research, which took ten years to complete, shows that lithium is essential for maintaining brain function and may provide protection against cognitive decline. The findings were explained by study authors Bruce Yankner and Liviu Aron.

“Most people associate lithium with psychiatric treatment. Our study shows, for the first time, that naturally occurring lithium plays a crucial role in maintaining brain health during aging—even at concentrations far below those used in clinical psychiatry,” they stated.

The study analyzed a series of experiments on mice and human brain tissue and blood samples from various cognitive health stages. The researchers found that lithium was significantly depleted in the brains of individuals with mild cognitive impairment, an early sign of Alzheimer’s.

“We found that lithium deficiency is one of the earliest biochemical signs of the disease, possibly years before clinical symptoms appear,” Yankner noted.

The research also highlighted that higher lithium levels in individuals correlated with better cognitive function. This raises questions as to why some people exhibit Alzheimer’s-like symptoms without developing the full disease.

In experiments with mice, reduced lithium levels led to accelerated brain pathology and memory decline. The researchers concluded that lithium binds to amyloid plaques—misfolded proteins associated with Alzheimer’s—thereby reducing its availability.

“In people that start experiencing memory loss, lithium gets trapped by amyloid plaques, reducing its function just when it’s most needed,” the authors explained.

The study also introduced a new lithium compound that avoids binding to amyloid plaques, restoring memory in experimental mice. If these findings hold true in humans, they could point toward lithium as a preventive measure against Alzheimer’s.

“The idea that lithium deficiency could be a cause of Alzheimer’s disease suggests a different therapeutic approach,” Yankner said, noting that trials are needed to confirm these results.

Furthermore, previous studies indicate that geographical areas with higher lithium levels in drinking water have recorded lower rates of dementia. Yankner’s team hopes that these findings could lead to routine blood tests to identify individuals at risk of Alzheimer’s.

“Our study adds to growing evidence that Alzheimer’s may be preventable—by keeping brain lithium at healthy levels as we age,” Yankner concluded.

The findings were published in the journal Nature. While the research shows promise, clinical trials are necessary to evaluate the effectiveness of low-dose lithium supplementation in humans.