How Much Sleep Is Needed for Glymphatic Flow (Brain Cleaning)?

One function of sleep is the clearance of toxic waste byproducts through a newly discovered drainage system in the brain. Glymphatic brain filtration may help explain why those who routinely get fewer than seven hours of sleep a night are at increased risk of developing cognitive disorders, such as dementia.

In the next video, I share the best sleeping position for glymphatic flow (

For how to sleep better in general, see How to Get a Good Night’s Sleep Without Sleeping Pills (

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Thanks for watching. I hope you’ll join in the evidence-based nutrition revolution!
-Michael Greger, MD FACLM

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