People who get more deep sleep appear less likely to develop Alzheimer’s. That may be because this phase of sleep allows the brain to clear out waste products.
During deep sleep, the brain appears to wash away waste products that increase the risk for Alzheimer’s disease.
A host of new research studies suggest that this stage of sleep — when dreams are rare and the brain follows a slow, steady beat – can help reduce levels of beta-amyloid and tau, two hallmarks of the disease.
“There is something about this deep sleep that is helping protect you,” says Matthew Walker, a professor of neuroscience and psychology at the University of California, Berkeley.
The research comes after decades of observations linking poor sleep to long-term problems with memory and thinking, Walker says. “We are now learning that there is a significant relationship between sleep and dementia, particularly Alzheimer’s disease.”
The strongest evidence involves deep sleep, he says. That’s when body temperature drops and the brain begins to produce slow, rhythmic electrical waves.
So Walker and a team of scientists set out to answer a question: “Can I look into your future and can I accurately estimate how much beta-amyloid you’re going to accumulate over the next two years, the next four years, the next six years, simply on the basis of your sleep tonight?” [ … ]