Shakespeare described sleep as “the main course in life’s feast, and the most nourishing.” New research suggests it may also be a key nutrient in warding off Alzheimer’s disease.
Poor sleep has long been linked to Alzheimer’s, but the relationship is akin to the chicken-and-egg conundrum. It isn’t clear which came first. During deep sleep, the brain produces slow electrical waves and flushes out neurotoxins including amyloid and tau, two hallmarks of the disease.
Studies have shown that even one night of lousy deep sleep can lead to an increase of amyloid. A week of disrupted sleep can raise the amount of tau, which is especially insidious because over time it can strangle neurons from the inside out.
Those with Alzheimer’s experience sleep disturbances years before they develop cognitive symptoms, but the pathology that underlies the disease can itself disrupt sleep. Poor sleep, then, may increase the risk of Alzheimer’s and be an early symptom of it. It’s also possible that those who are at higher genetic risk for the disease are more prone to sleep disturbances.