I’m about to reveal the “sweet spot” for sleep that can help you maintain good mental and physical health.
Once we reach middle age, we need to sleep a certain number of hours each night to maintain good health. And that number is 7. No more, no less.
Researchers at the UK’s University of Cambridge analyzed data from nearly half a million people aged 38 to 73.
The result: 7 hours a night was the optimal amount of sleep for cognitive performance. The data also showed that fewer than 7 hours of sleep AND more than 7 hours was linked to reduced mental processing speed, visual attention, memory, and problem-solving skills. Study participants who slept 7 hours a night also experienced less anxiety and depression, and higher overall wellbeing, compared to when they slept longer or shorter periods of time.
The researchers say one reason is that getting less than 7 hours a night means people are getting less “deep sleep.” And without that restorative deep sleep, damaging proteins build up in the brain, which is one of the hallmarks of dementia. Too little sleep also hurts the brain’s ability to flush out toxins, which can trigger inflammation and age-related brain diseases.
And sleeping more than 8 hours a night after middle age is linked to depression.
So, to maximize your brain function in middle age and beyond? 7 hours is your sweet spot.