Are you feeling very ‘grotty’ in the mornings? You could be getting too much sleep.
Research has found that if we sleep for longer than 7 hours it could in fact have the opposite effect.
The study was led by researchers at Washington University School of Medicine in St. Louis.
“It’s been challenging to determine how sleep and different stages of Alzheimer’s disease are related, but that’s what you need to know to start designing interventions,” said first author Brendan Lucey, MD, an associate professor of neurology and director of the Washington University Sleep Medicine Center. “Our study suggests that there is a middle range, or ‘sweet spot,’ for total sleep time where cognitive performance was stable over time. Short and long sleep times were associated with worse cognitive performance, perhaps due to insufficient sleep or poor sleep quality. An unanswered question is if we can intervene to improve sleep, such as increasing sleep time for short sleepers by an hour or so, would that have a positive effect on their cognitive performance so they no longer decline? We need more longitudinal data to answer this question.”
The researchers found a U-shaped relationship between sleep and cognitive decline. Overall, cognitive scores declined for the groups that slept less than 4.5 or more than 6.5 hours per night — as measured by EEG — while scores stayed stable for those in the middle of the range. EEG tends to yield estimates of sleep time that are about an hour shorter than self-reported sleep time, so the findings correspond to 5.5 to 7.5 hours of self-reported sleep, Lucey said.
“It was particularly interesting to see that not only those with short amounts of sleep but also those with long amounts of sleep had more cognitive decline,” said co-senior author David Holtzman, MD, a professor of neurology. “It suggests that sleep quality may be key, as opposed to simply total sleep.”
Each person’s sleep needs are unique, and people who wake up feeling rested on short or long sleep schedules should not feel compelled to change their habits, Lucey said. But those who are not sleeping well should be aware that sleep problems often can be treated.
Ideas to help with lack of sleep may include;
- Turn off all phones and computers by 6pm – this helps the mind to relax
- Have a warm relaxing bath, putting in your favourite bath bombs and oils
- Go for a walk for 20 minutes to release excess energy
- Breathing exercises can help to relax the body, many of us start to breathe shallow when things are on our mind
- Read one of your favourite books