Fifty years ago conventional scientific wisdom was that the need for sleep declined gradually but consistently across the lifespan. By the time adults approached their retirement years, according to this view, five or six hours of sleep each night could be both normal and adequate.
Current understanding of older adult needs for sleep point in just the opposite direction. From ages 35 to 85 we lose on the average of an hour of sleep per night. But according to psychologist Sean Drummond, a sleep expert at the University of California, San Diego, “The biggest, most common, most robust change is that we spend more time awake in the middle of the night.” Having periods awake during the night indicates a decrease in sleep efficiency, but does not indicate a decreased need for sleep.
The effects of lack of sleep can mimic the effects of aging, making our brains less able to learn and recall facts. Drummond found that it was not the quality of sleep, but the actual number of hours of sleep that improved performance of older adults on memory tasks. Lack of sleep effects brain performance in ways similar to aging. And Drummond speculates that getting an adequate quantity of sleep can prevent aspects of the cognitive decline that accompany growing older.
Learning and memory seem particularly sensitive to adequate sleep. “It’s critical to sleep before learning. Sleep almost prepares the brain like a dry sponge to soak up new information,” according to Dr. Matthew Walker of the University of California at Berkeley
Further, getting enough sleep is likely to contribute to longevity, support the immune system, support healthy metabolism, and foster other restorative functions like muscle growth, tissue repair, protein synthesis and hormone release according to the Division of Sleep Medicine at Harvard Medical School. Sleep has also been found to retard the development of Alzheimer’s Disease and reduce the pain of arthritis.
In one article we cannot cover all the positive benefits of sleep for those of us who are retired. But remember getting enough sleep can make us smarter, healthier, and even better looking. Seven, eight or even nine hours of sleep a night, every night, is the prescription. And a cat nap during the day can have the same helpful results. Don’t be so concerned if you wake up in the middle of the night and need to walk around, snack, or read for a little while. Go on back to bed. Remember for older adults, the quantity of sleep can be even more important than the quality. Happy dreams!