Lithium Deficiency Identified as a Potential Driver of Alzheimer’s Disease Onset
CAMBRIDGE, Massachusetts, United States – August 7, 2025: Big news from Harvard Medical School! Scientists there think they’ve found a direct link between not enough lithium in the brain and the start of Alzheimer’s. They’re saying that not having enough of this trace element could be a key trigger for the brain disease we didn’t know about before. The study, which you can find in the Nature journal, shakes things up! It shows that when Alzheimer’s starts and those toxic amyloid-beta plaques form, they grab lithium. This lowers lithium levels and sets off a chain reaction that looks a lot like Alzheimer’s getting worse. This discovery gives us a different idea about how Alzheimer’s starts. It also suggests we could treat it by getting lithium levels back up.
Lithium: Not Just for Moods
For years, lithium has been known to help people with bipolar disorder feel more stable. But this new research from Bruce Yankner’s team at Harvard suggests lithium does more than that. They think even small amounts of lithium are important for keeping brain cells healthy and helping them resist aging.
Some studies hinted at this before, showing that when there’s more lithium in drinking water, fewer people get dementia. Now, the Harvard team has a specific reason why this might be happening. They’ve found that lithium isn’t just helpful; it’s essential, and when you don’t have enough, things can go wrong.
How Plaques Steal Lithium
The main thing they found is that when amyloid-beta proteins start clumping together to form plaques, they act like a lithium sink. They grab lithium and pull it out of the brain. This is one of the first things they saw in both human brains and mice, even before people had many symptoms.
When lithium drops, it causes problems for brain cells, including neurons and microglia (the cells that clean up the brain). The researchers discovered that without enough lithium, microglia don’t do as good of a job clearing away amyloid plaques. This means more plaque buildup, which grabs even more lithium, making the problem snowball.
Mice Give Us Clues
To test their ideas, the team did some tests on mice. They fed healthy mice a diet low in lithium, and their brain lithium levels dropped to what you see in people with Alzheimer’s. This led to faster brain aging, brain inflammation, and loss of connections between brain cells, which made the mice not think clearly.
When they did this to mice that were made to get Alzheimer’s, things got worse! The lithium drop sped up the forming of amyloid-beta plaques and neurofibrillary tangles (the two main signs of the disease). This strongly suggests that lithium levels and Alzheimer’s are related.
A New Way to Fight Alzheimer’s?
Because of these findings, the researchers are trying out new treatments. They made a new form of lithium, lithium orotate, that’s designed to avoid the amyloid-beta plaques and get lithium right to the brain cells.
When they gave this to mice, it worked really well! It reversed the bad changes caused by Alzheimer’s, lowered the amount of amyloid and tau stuff, and helped the mice remember things again. This is cool because it might be a way to treat the cause of the disease, not just the symptoms.
What’s Next for People?
The researchers are excited, but they know they need to be careful. These results are good in mice, but they need to see if they hold up in people. They think one thing they could do is test people’s blood to see if they have low lithium levels.
If they can find people with low lithium, they might be able to help them early on. Professor Yankner hopes that keeping lithium levels healthy as we get older could be a simple way to prevent or delay Alzheimer’s. This work has started an exciting chapter in the search to understand and beat this terrible disease.
