According to a study published in Nature Aging, seven hours is the ideal amount of sleep for people who are middle-aged and older. Specifically, the research that this is the optimal amount of sleep for cognitive performance and good mental health.
The researchers examined data from nearly 500,000 adults ages 38-73 from the UK Biobank. Study participants provided information about their sleep patterns, mental health and well-being, and they took part in a series of cognitive tests. Brain imaging and genetic data were available for almost 40,000 of the study participants.
Results revealed that lack of sleep and too much sleep were associated with impaired cognitive performance, such as processing speed, visual attention, memory and problem-solving skills. Seven hours of sleep per night was the optimal amount of sleep for cognitive performance and good mental health.
"Getting a good night's sleep is important at all stages of life, but particularly as we age. Finding ways to improve sleep for older people could be crucial to helping them maintain good mental health and well-being, and avoiding cognitive decline, particularly for patients with psychiatric disorders and dementias," said professor Barbara Sahakian from the Department of Psychiatry at the University of Cambridge.