The glymphatic system works by bringing cerebrospinal fluid to the brain while we sleep, which removes protein waste products like tau proteins and amyloid beta—which are well known risk factors for Alzheimer’s and dementia.

And for starters, Nedergaard notes, there appears to be a bidirectional relationship between sleep and the glymphatic system, and neurological conditions. Namely, she writes, cardiovascular, neurological, and several inflammatory diseases have all been shown to worsen glymphatic function—as does chronic stress and aging in general.

Further, this toll on the glymphatic system predisposes individuals to neurodegenerative diseases like Alzheimer’s.

But on the flipside, Nedergaard explains, better sleep could mean an improved glymphatic system. “Common approaches that are known to reduce stress and improve sleep and life quality all act by improving glymphatic flow and restoring brain homeostasis,” she adds.