Experts have repeatedly stated about the negative effects of lack of sleep. But the excess of sleep can be hazardous to health.
Previously, scientists found that too much sleep harms the brain. New work by Chinese scientists showed that people who do not mind a good NAP in the afternoon or sleeping more than nine hours a night may increase the risk of stroke.
the study involved 31750 people in China, who initially had serious health problems. The average age of the volunteers was 62 years.
the participants of the experts have observed on average for six years. During this period, 1557 man suffered a stroke.
the Researchers collected medical data and conducted surveys to get more information about the habits associated with night sleep and day time activities of people (note that the daily routine of many people in China include NAPs).
it turned Out that 8% of the participants used to NAP during the day more than 90 minutes. But 24% admitted that their night’s sleep usually lasts nine hours and more.
analysis of the data showed that people who sleep nine or more hours at night, later 23% more likely to suffer from stroke than those who sleep seven to eight hours (this is set by experts a normal night’s sleep for adults).
At the same time, participants whose night’s sleep had lasted at least seven hours or eight to nine hours, the risk of stroke was lower than those who slept more than seven but less than eight hours.
Volunteers who regularly slept in the day more than 90 minutes, had 25% more chance of getting a stroke than those whose afternoon NAP lasted no more than 30 minutes.
on average, among people who are accustomed to sleep at night and also indulge in a long afternoon sleep, the incidence of stroke was 85% higher than those who did not NAP a day and slept at night for seven or eight hours.
All these results were adjusted for otherswhich factors that may affect the risk of stroke. These include hypertension, diabetes and Smoking.
in addition, researchers asked volunteers about the quality of sleep. It was found that the participants who slept poorly at night, 29% often faced with a stroke than people who reported high sleep quality.
the Authors note that further research was needed to determine a causal relationship between the duration of day and night sleep and risk of stroke in middle-aged and elderly.
But the researchers already have some hypotheses. So, earlier it was found that people used to sleep both day and night, occur unfavourable changes in cholesterol levels and increased waist circumference. This risk factors for stroke, reminiscent of scientists.
Also, long sleep may indicate an inactive lifestyle, which increases the likelihood of stroke.
by the Way, the authors also noted that in this case, information about sleep was gathered from the questionnaires and the exact duration of sleep and wakefulness of the participants was not monitored.
read More about the work done are described in the article submitted to the journal Neurology.
earlier, experts have found that sleep more than nine hours may be an early sign of dementia.
Also “Conduct.Science” (nauka.vesti.ru) talked about the benefits of a short daytime sleep for children, teenagers and adults, and that sleep on the weekends is unhealthy.