You may think of Alzheimer's disease as something that impacts only your friend's grandpa, but we're learning that cognitive decline is actually shockingly common. In fact, Alzheimer's Association experts estimate that 12 to 18 percent of Americans 60 and older experience some form of mild cognitive impairment (MCI), which often progresses to officially diagnosable forms of dementia, including Alzheimer's disease.
This week, the U.S. Food & Drug Administration (FDA) fast-tracked aducanamab, the first drug that might potentially slow the progression of early-diagnosed Alzheimer's. But there's still no cure for any form of dementia, so our best bet is to do everything possible to prevent it in the first place. We've recently learned that walking three times per week, playing music and eating a Mediterranean-style diet can help keep your brain healthy as you age.
New research published June 1 in PLOS Biology adds another brain-benefiting tip to our Alzheimer's prevention arsenal: deep sleep.
Pennsylvania State University scientists discovered that sleep-dependent brain activity-the kind that occurs during deep, restful non-rapid eye movement (NREM) sleep-can help the body excrete toxic proteins related to Alzheimer's disease. (ICYMI, we just learned that a healthy gut can help you score more high-quality, deep sleep so be sure to load your diet with these probiotic, prebiotic and fermented foods!)
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Extensive research suggests that one way Alzheimer's disease develops is when levels of the proteins amyloid-β (Aβ) and tau build up in the brain. This often occurs over the course of 10 to 20 years prior to an official diagnosis. By the way, this is not the first research that hints to this brain protein burden and sleep link: In 2018, scientists found that a single night of sleep deprivation increases the Aβ load within the brain.
The cerebrospinal fluid (CSF) can usher these waste products out of the body through the glymphatic system, which is part of the central nervous system. Glial cells in the brain team up with blood vessels to help protect neurons from physical and chemical damage. If the glymphatic system can't drain this "brain waste" effectively, the extracellular accumulation of these proteins could progress to Alzheimer's disease.
But deep sleep might help the brain wash away these Alzheimer's-related toxins. During NREM sleep, which is the kind that occurs when it's *really* tough to wake up because you're so fully "off," the brain creates slow, steady electrical waves that act as an internal cleaning mechanism.
"The study linked the coupling between the resting-state global brain activity and [CSF] flow to Alzheimer's disease pathology. The finding highlights the potential role of low frequency (less than 0.1 [hertz]) resting-state neural and physiological dynamics in the neurodegenerative diseases, presumably due to their sleep-dependent driving of [CSF] flow to wash out brain toxins," Xiao Liu, Ph.D., an assistant professor of biomedical engineering at the Pennsylvania State University, tells Medical News Today.
The study authors caution that this is not a proven cause-and-effect scenario (yet), but recommend that sleep analysis be added to Alzheimer's disease detection protocol.
Regardless, carving out time for enough (AKA seven to nine hours) of restful sleep certainly doesn't sound like a bad prescription! In case you could use a little R&R rehab, we spoke to a sleep expert to round up four ways to get a better night of sleep.