A team of scientists in Japan has found a promising way to support memory and brain health as we get older—by using something that comes from melatonin, the natural hormone that helps us sleep.
This research was led by Tokyo Medical and Dental University and offers new hope for preventing memory loss in aging.
Melatonin is a chemical made by the body that helps regulate sleep. But the study found that melatonin may also help protect memory—thanks to the substances it breaks down into after being processed in the body. These are called metabolites.
The scientists focused on one special metabolite called AMK. They wanted to know if AMK could help prevent or reduce memory loss, which is common as we age.
To test this, they used mice, which are often used in memory research. Mice have a natural habit: if they see a new object and one they’ve already seen, they’ll usually spend more time looking at the new one. This shows they remember the old one. But if a mouse has memory problems, it won’t tell the difference and treats both objects the same.
In the experiment, researchers first showed mice several objects to get them familiar. Then they gave the mice melatonin or its metabolites, including AMK. The next day, the scientists tested whether the mice could remember the familiar objects.
The results were exciting. The mice that received melatonin’s by-products had better memory, especially those that got AMK. They were able to recognize the familiar objects and showed more interest in the new ones.
The researchers also studied the mice’s brains. They found that AMK and the other by-products had gathered in the hippocampus, the part of the brain responsible for memory.
When they stopped melatonin from turning into AMK, the memory benefits went away. This means AMK is likely a key part of how melatonin helps the brain remember things.
Even more encouraging was the fact that AMK helped not just young mice, but older ones too. Older mice, which usually have memory problems, also showed big improvements after receiving AMK. That’s important, because memory loss becomes more common as people age.
In humans, memory problems in older age can lead to conditions like Mild Cognitive Impairment (MCI), and sometimes Alzheimer’s disease. That’s why this study is so important. It gives scientists a new path to explore for helping people keep their memory strong.
While this study was done in animals, it suggests that melatonin’s by-products—especially AMK—might one day be used to help people stay sharp as they age. If future studies in humans show similar results, it could lead to new ways to slow down or even prevent memory loss.
The research was published in the Journal of Pineal Research, a journal focused on melatonin-related studies. More research is needed, but this discovery brings new hope that a familiar sleep hormone might also protect our brains as we grow older.
If you care about sleep, please read studies that Sleeping pill lowers key Alzheimer’s disease markers and Scientists discover the link between sleep apnea and dementia risk.
For more health information, please read studies that Common sleep supplement could improve memory and Scientists find link between short sleep and higher risk of long COVID.
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