Too Little, and Too Much, Sleep Ages the Brain

Achieving quality sleep is an anti-aging essential, yet many of us fail to feel rested upon waking.  Elizabeth Devore, from Brigham and Women's Hospital (Massachusetts, USA), and colleagues evaluated associations of sleep duration at midlife and later life, and change in sleep duration over time, with memory in 15,263 participants of the Nurses' Health Study. Participants were female nurses, ages 70 or older and were free of stroke and depression at the initial cognitive assessment.  The team found that women who slept five or fewer hours, or nine or more hours per day, either in midlife or later life, can cause memory declines equivalent to nearly two additional years of age.  Further, the researchers noted that women whose sleep duration changed by greater than two hours per day over time had worse memory than women with no change in sleep duration.  The study authors submit that: “Extreme sleep durations at midlife and later life and extreme changes in sleep duration over time appear to be associated with poor cognition in older women.”