Tossing and turning in bed? You might have more memory problems when you’re old and gray. New research reports that people who wake more than five times an hour at night build up more amyloid plaques (proteins linked with Alzheimer’s disease). To collect the data, the researchers asked 100 people who were all free of dementia (ages 45 to 80), half with a family history of Alzheimer’s, to fill out sleep surveys and wear a device for two weeks while they slept. Collectively, the group averaged about eight hours in bed each night, 6.5 hours of actual sleep, and some of the sleepers were more “efficient” at staying asleep than others. The efficient sleepers—those who actually slept more than 85 percent of the time—were less likely to build amyloid plaques as well. A great reminder to get some shut-eye—it matters!

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