Science Says Sleeping for Less Than Six Hours Each Night May Increase Your Risk of Dementia by 30 Percent

Health experts have long touted the benefits of getting a good night's sleep. From a reduced risk of obesity and heart disease to less stress and an overall better outlook on life, getting at least seven to eight hours of sleep each night can improve our health. A groundbreaking new study is further proving that sleep can play a major role in our health later than life. Researchers found that getting less than six hours of sleep each night during your 40s and 50s may increase your risk of dementia by 30 percent.

tired woman at work desk
tired woman at work desk

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The study, which was published in the journal Nature Communications, followed nearly 8,000 participants for 25 years and found that there was a higher risk of dementia in adults ages 50 and 60 who slept less than six hours each night, compared to those who got at least seven hours of sleep. Additionally, persistent short spurts of sleep between the ages of 50 through 70 was also associated with a 30 percent increased dementia risk, which was independent of "sociodemographic, behavioral, cardiometabolic, and mental health factors," including depression, the study said. This sleep study found no significant differences between dementia risks among men and women.

Related: How to Combat Short-Term Insomnia for a Better Night's Sleep

"Sleep is important for normal brain function and is also thought to be important for clearing toxic proteins that build up in dementias from the brain," said Tara Spires-Jones, who is deputy director of the Centre for Discovery Brain Sciences at The University of Edinburgh in Scotland, in a statement.

Tom Dening, who heads the Centre for Dementia at the Institute of Mental Health at the University of Nottingham in the UK, said that this study cannot entirely establish cause and effect between a lack of sleep and dementia. "Maybe it is simply a very early sign of the dementia that is to come, but it's also quite likely that poor sleep is not good for the brain and leaves it vulnerable to neurodegenerative conditions like Alzheimer's disease."

Previous health studies also found a link between a lack of sleep and cognitive impairment later in life. A 2017 study found that people who get less REM, or dream-stage sleep, may be at higher risk for developing dementia. Although there is no proven way to prevent dementia altogether, experts agree that maintaining a healthy lifestyle and diet can certainly help. "The best evidence suggests that not smoking, only drinking in moderation, staying mentally and physically active, eating a balanced diet, and keeping cholesterol and blood pressure levels in check can all help to keep our brains healthy as we age," Sara Imarisio, who leads strategic initiatives at Alzheimer's Research UK, told CNN.