And with Britain being the most sleep deprived nation in the world, according to a separate annual relaxation survey, scientists say a good night’s sleep has never been more important. Research author Dr Severine Sabia, University of Paris, said: “This study highlights the importance of good sleep for brain health.” Scientists followed 7,959 Whitehall employees for more than 25 years. Those who slept six hours or less at age 50 or 60 were more likely to develop the disease.
But dementia rates have increased by 30 percent among people with consistently short sleep patterns between the ages of 50 and 70. This was compared to peers who managed the recommended seven or eight hours.
Dr Sabia said: “Regularly sleeping six hours or less a night in middle age is associated with a higher risk of dementia. This adds to the growing evidence that sleep is essential for health.”
She said sleep was necessary to remove unwanted brain proteins called beta amyloid. They kill neurons, leading to memory loss and confusion.
The accumulation of these proteins is found in patients with Alzheimer’s disease.
Over 920,000 people in the UK are living with dementia.
Professor Derk-Jan Dijk, University of Surrey and UK Dementia Research Institute Group Leader, said: “This is solid research that adds to the growing evidence for a link between sleep and dementia. The study was published in Nature Communications.