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We sleep long enough, but not well enough

17 November 2020

The treatment of sleep problems should focus more on the quality of our sleep. We sleep long enough, but not well enough. This is according to one of the largest studies ever done on sleep behaviour. Poor sleep is harmful to health.

Fall asleep and sleep through

About 10 to 20 percent of the Dutch sleep badly. More than 90 percent achieve the recommended sleep time of 7-9 hours per night, but have problems falling asleep and staying asleep. Also, many people do not wake up rested. ‘And sleeping long enough is certainly not the same as having a good night’s sleep,’ says research leader Henning Tiemeier of Erasmus MC. “A really good sleep keeps your brain healthy and ensures that the body recovers.” In the short term, good sleep improves memory and concentration. In the long term, sleeping well can reduce the risk of brain disorders such as depression, stroke and dementia.

In total, the sleep of more than 1.1 million people has been examined in the largest study of its kind ever; 200,358 Dutch, 471,759 people from Great Britain and 409,617 people from the United States aged 1 to 100 participated. For the Netherlands, this even means that the sleep of more than 1% of the Dutch population has been studied. The sleeping behavior of the Dutch resembles that of the British. Americans have up to three times more sleep complaints. The reason for this has not been investigated in this study.

Improve sleep quality

The researchers argue that the treatment and prevention of sleep problems should focus more on improving sleep quality, such as falling asleep faster or staying asleep, rather than simply trying to prolong sleep. Doctors and researchers now often focus only on the duration of sleep. “We are therefore not tackling the problem thoroughly enough,” says sleep researcher Annemarie Luik of Erasmus MC.

The importance of good sleep is underestimated by many people. People with sleeping problems can in many cases improve their sleep quality themselves. Liège: “For example, make sure that your bedroom is quiet and dark, and do only relaxing activities at least an hour before going to bed and not intensive sports. It also helps to get up at the same time every day and not drink coffee or alcohol in the hours before going to bed.”

More research

However, this does not solve all sleeping problems, warns co-researcher Eus Van Someren of the Netherlands Institute for Neuroscience. Despite these good sleeping habits, about 10% of the population suffers from chronic insomnia. “This disorder is serious and is still under-researched. A missed opportunity, because it is the most important risk factor for even more suffering, especially by developing an anxiety disorder, depression or a post-traumatic stress disorder.’ Van Someren wants to do more research on this with the help of many volunteers who sleep poorly. They can participate via

The researchers from the Netherlands Institute for Neuroscience and Erasmus MC, among others, have published their findings in the leading scientific journal Nature Human Behaviour. Our poor sleep quality can be harmful to our health. The project is financed by the Brain Foundation and forms the basis for policy-making on sleep by the Brain Foundation and the Trimbos Institute.


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