In order to preserve girlish beauty for a long time, to be vigorous and full of strength, it is necessary to sleep at least nine hours a day - so the famous Sophia Loren thought and this is what she did all her life. But the "iron lady" Margaret Thatcher slept no more than four hours a day. At the same time, anyone could envy her cheerfulness and ability to work. And she always looked great. So how much should a woman sleep in order to maintain health, vigor, beautiful appearance, mental and physical performance?
“More than a man, anyway,” says Jim Horn, director of the Loughborough University Sleep Research Center. According to him, this is due to the fact that women, unlike men, as a rule, solve several tasks at once, performing many duties at the same time. Therefore, the potential of the brain in women is involved more than in men, therefore, they should rest longer.
The specialists of the Sleep Center conducted research on the effect of sleep duration on men and women. It turned out that the lack of sleep affects women more negatively than the strong half of humanity. From lack of sleep, a woman can even experience psychological stress. Chronic sleep deprivation is defined as a constant sleep duration of less than seven to eight hours. Jim Horn explains that when we sleep, our brain, like a computer operating system, performs defragmentation, that is, it processes all the information received during the day and "puts it" on the shelves. Sleep deprivation disrupts the effective communication of synapses (contacts between two neurons, or a neuron and a receiving cell) and over the years can lead to Alzheimer's disease.
This problem was investigated in more detail at a private research institution - Duke University (North Carolina, USA). Its specialists monitored the condition of more than two hundred middle-aged men and women. For the study, people were selected who did not have sleep problems, did not take any medications, and were nonsmokers.
The subjects wrote down their routine, their state of health every morning, immediately after waking up. They also had blood samples taken in the morning to track specific biomarkers.
It turned out that more than a third of the subjects had sleep problems, although they were unaware of it. Moreover, in women, they were more pronounced, as evidenced by both the psychoemotional state and the blood test, and such a high level of c-reactive protein that it caused the risk of cardiovascular diseases.
One of the most negative factors of sleep deprivation in women is the increased level of insulin in the blood, which over time can lead to type 2 diabetes.
In their research, Harvard University researchers decided to identify a specific relationship between sleep duration and diabetes. Their study involved nearly 60 thousand women aged 55 to 83 years. According to the results of these studies published in the journal Diabetologi, women whose sleep lasted less than six hours was at increased risk of diabetes. Ladies who spent seven to eight hours of sleep each day had a minimal risk of developing diabetes. But those who, compared to the beginning of the study, increased their sleep by two hours (regardless of how long it was before), a 15 percent increased risk of acquiring diabetes of the second degree.
Summarizing all the data, scientists at Harvard University came to the conclusion that on average a woman should sleep at least seven, but not more than nine hours a day.
Scientists at the University of California, San Diego will argue with this. For 14 years they researched another relationship - sleep and life expectancy.The experiment involved nearly 500 women. It began in 1995, and already in this century, fourteen years later, the results were summed up. All this time, the condition of the subjects was constantly monitored. Particular attention was paid to the frequency and duration of sleep. During the test, a fifth of the volunteers, mostly of advanced age, died. Most of the older women who saved their lives slept between five and six and a half hours a day. From what scientists have deduced the most optimal duration of sleep for women - four hours of sleep is not enough, and seven is too much.
Now back to Sophia Loren and Margaret Thatcher. The duration of sleep they set does not fit into this framework in any way. And it shouldn't, say Pennsylvania and Washington university scholars. In order to identify the relationship between the duration of sleep and a person's well-being, they conducted an experiment. Fifty men and women with excellent health, who are accustomed to sleeping 7-8 hours a day, were divided into four groups.
In the first, people were not supposed to sleep at all for three days. In the second, they slept for four hours, in the third, six, and in the fourth, eight. The last three groups followed the new regime for two weeks. All this time, doctors monitored their condition.
The result of the experiment: those who slept for eight hours did not show any changes in their state of health. Various deviations (decreased cognitive functions, deterioration of reaction, memory lapses) were revealed in those who slept for six hours a day. Those who slept for four hours - these deviations were recorded more often than the previous ones. The worst indicators were for those who did not sleep at all.
The main conclusions of the experiment are that any person (regardless of gender) needs to sleep as much as his body needs. 7-8 hours of this is indeed the optimal sleep duration, but it is average. Each person is different, and each has its own length of time to recover the body. Stories are known of cases where people were content with two hours of sleep a night, such as Thomas Jefferson. The same Margaret Thatcher, according to the testimony of her secretary, on some days managed one and a half or two hours of sleep. However, firstly, these are extraordinary personalities, and, secondly, lack of sleep tends to accumulate. For example, the participants in the experiment at US universities deteriorated gradually. Even when they clearly did not feel the lack of sleep, it was reflected in various indicators of their well-being.
With different conclusions from the studies carried out, all scientists who have studied the problem of sleep duration are unanimous in only one thing: if a person's regular sleep duration exceeds 12 hours a day, he needs to see a doctor.