7 hours of sleep is optimal amount, new research suggests

7 hours isthe magic number according to new research that looked at the connection between sleeping and age-related memory loss. Researchers at the Brigham and Women’s Hospital in Massachusetts found that extreme sleep duration,either too much or too little, in middle-aged women led to worse memory later in life.
The same was observed in women who reported erratic sleep patterns: those whose sleep durations changed by more than two hours a day also increased their risk of developing faulty memories later in life compared to those who kept regular sleep schedules.
"Given the importance of preserving memory into later life, it is critical to identify modifiable factors, such as sleeping habits, that may help achieve this goal," said study co-author Elizabeth Devore in a statement.
“Our findings suggest that getting an ‘average’ amount of sleep, seven hours per day, may help maintain memory in later life and that clinical interventions based on sleep therapy should be examined for the prevention of cognitive impairment."
For the research, scientists looked at the past sleep patterns and memory skills of about 15,260 female nurses aged 70 or older who were participants in the long-running Nurses’ Health Study.