Human beings spend about one third of their life sleeping. But the place of sleep in the life of human beings is not restricted to this time; the quality of a person’s sleep also affects the waking hours. Moreover, the growth hormone secreted during sleep plays an essential role in the development of children. On the other hand, other functionary hormones are employed in the care, restoration, and refreshment of the body.
Sleep is known as one of the basic needs that are necessary to sustain life in addition to eating, drinking, and respiration. There have been some studies about the endurance of people to sleeplessness. The period that a normal person can do without sleep is three or four days on average. At the end of this period, some problems arise such as absent-mindedness, irritability, not knowing the time, hallucinations, stammering, not understanding what is said, trembling of the hands, inflammation in the body, pain, and defective vision. The longest one of these experiments was carried out on an American undergraduate student. After 11 days of sleeplessness, the experiment was ended when his health was under serious threat.
Various studies on sleep show that the period of sleep we need for a healthy and balanced life is between 4-10 hours for an average person, depending on genetic factors. It is about 6-8 hours for adults. On the other hand there are some studies that show that we do not have to sleep eight hours a day, on the contrary six, five, even four hours can be sufficient.
Those who sleep too much or very little tend to face health problems as compared to those who enjoy regular sleep. In a long-term study, more than 71,000 women were observed over ten years and two important points were determined: firstly, long hours of sleep increased the risk of heart disease; secondly, those who slept too much faced as many health problems as those who slept very little. Sleeping too much can cause obesity, diabetes, high blood pressure, a decrease in muscle volume, a reduction in the immune system function, and depression.
We can see in our own experiences and that of others that there is no direct proportion between the amount we sleep and the amount we rest. A person who sleeps little can feel rested more than one who sleeps too much; the former one has had a restful sleep that is sufficient.
There are some important points in daily life and prior to sleeping that need to be focused on:
- One should have a light meal in the evening, at least two hours before sleeping. Heavy meals carry risks for those who have problems with snoring and respiration. Drinks that have stimulating effect, such as tea, coffee, and cola delay sleeping.
- The sleeping atmosphere is important. The ideal atmosphere for quality sleep requires low light, quiet, and a warm room with a bed which is not too hard or too soft.
- One should have a regular sleeping habit. One of the conditions for enjoying quality sleep is to sleep and wake up at the same hours. It is particularly important to have regular sleep on week days. The disruption of this regularity at the weekend is one of the stumbling blocks standing in the way of a quality sleep.
- One should lie on the right or left side. Lying flat on one’s back or lying prone can bring certain problems. Snoring or interruption of respiration only occurs while lying flat on one’s back. The most suitable position for sleeping is to turning to the right or left. A person unconsciously moves and changes position 10 or 15 times during his sleep as a result of Divine Mercy. Here one remembers the verses of the Holy Qur’an about the sleeping positions of the “people of the cave”: . . . We caused them to turn over to the right and the left... (Kahf 18:18). It is striking that there is no expression of lying flat on one’s back or lying prone. Moreover lying on one’s right is also the tradition of the Prophet Muhammad, peace and blessings be upon him.
In order to determine the ideal hours for sleeping it is important to know the events that occur in the human body during sleep at different periods. We should know that the pineal gland is installed in the human body as a system. Located in the mid-lower part of the brain, this gland has to secrete certain hormones. One of them is melatonin. God eases sleep with this hormone and regulates the cycle of sleep and waking. The secretion of melatonin begins in the evening and goes on until it peaks at two or three o’clock. That means a system was innately installed in the human body that makes sleeping easy in the evenings. On the other hand, being exposed to extreme artificial light, watching television at midnight, and external effects, such as electromagnetic fields, decrease the production of melatonin and is harmful to the running of the system.
Further research has shown that sleep plays an important role in bringing the TSH hormone under control. TSH helps control our metabolism and, indirectly, our levels of energy. Therefore, nowadays those who have low TSH level, that is about 25 or 35 %, are recommended to wake up during the night. This new scientific research is completely in accordance with the habit of the Prophet; he used to sleep shortly after Isha prayer (earlier than most people sleep nowadays), and wake in the very early morning hours (sometimes as early as midnight) again to pray. This sleeping system takes its resource from Holy Qur’an. God orders the Prophet in the Qur’an as follows:
O you enwrapped one! Rise to keep vigil in the night, except a little; Half of it, or lessen it a little; Or add to it (a little); and pray and recite the Qur’an calmly and distinctly (with your mind and heart concentrated on it). We will surely charge you with a weighty Word (and with applying it in your daily life and conveying it to others). Rising and praying at night impresses (mind and heart) most strongly and (makes) recitation more certain and upright.” (Muzammil 73:1-7)
There are also some facts about napping. The best time for a nap is midday according to the experts. A half-hour siesta consisting of a deep and slow period is equal to two hours of nighttime sleep. Therefore when one sleeps at midday, they will need less sleep at night. Midday is known as being the least efficient period of day and human beings have the tendency to sleep at this time. By having a short siesta, one spends other periods in the day more energetically and efficiently. This sleep is frequently practiced in hot climate zones. In some companies in Japan, certain places are allotted in order to encourage people to sleep at midday.
The day time nap is a sleep that the Prophet Muhammad practiced and advised, which is known as “qaylula.” This sleep lasts from mid-morning to just past noon. This sleep is part of the Prophet’s tradition as it allows a person to rise at night to pray. In this way one is prepared for midnight prayer.
There are two more periods of time in the day and it is not recommended to sleep at these times. The first one is “ghaylula.” This is from pre-dawn to forty minutes or so after the sun has risen, the time when prayer is allowed, but not recommended. Sleep at this time is contrary to the practices of the Prophet. The time most appropriate for preparing to work for one’s livelihood is when it is cool. When this time has passed, lethargy descends. It has been established through numerous experiences that just as this is detrimental to that day’s labor and indirectly to one’s livelihood, so also is it the cause of unfruitfulness. In a hadith, the Messenger of God said: “The early morning has been blessed for my Community.”1 As a matter of fact, when the Prophet was about to send an army, he sent it at an early time of the day. Sahr ibn al-Wada, the conveyor of above-mentioned hadith, was a merchant and used to begin his travels very early in the morning. Therefore, he became rich and he had much property. It is also a known fact that the best time of working for sustenance is the early morning.
The other sleep that is not recommended is “faylula.” This is from the afternoon prayer till sunset. This sleep leads to a diminution of life, that is, it makes the life of that day shorter and makes it pass in a state of semi-sleep due to drowsiness, thus causing a physical deficiency. So too, in an immaterial aspect, since most of the results of that day, material and immaterial, became apparent after the afternoon prayer, to pass that time in sleep is as if one has prevented the results of one’s action and makes the day feel as though it has not been lived.
In brief, the “sleep” mentioned in the Holy Qur’an is a great bounty for human beings. However as with all bounties, it is important to find the middle course in sleeping if we want to live a balanced life and to benefit from this bounty during the recommended hours and in the recommended ways.