It is widely accepted in modern culture that people should eat three meals: breakfast, lunch, and dinner. Nutritionists generally recommend adding two snacks (one in the morning and the other in the afternoon) to help control appetite.

Interestingly, the practice of eating three meals a day is a recent phenomenon. Ancient Romans had only one meal, which they usually had at about four in the afternoon, and they believed it was unhealthy to eat more than once a day. What the Romans ate in the morning and at noon was very light and fast [1]. Later, rules in monasteries affected people’s behavior around food and drink.

During the industrial revolution, breakfast gained importance; workers needed food before work. And dinner didn’t become popular – at least in its current form – until the prevalence of artificial lighting made it possible to eat before dawn and after dusk [2]. The understanding that eating three meals a day is a healthy choice stems from a combination of belief, culture, and early epidemiological studies [3].

There are studies suggesting that having a regular eating habit positively impacts health, regardless of frequency of meals. On the other hand, in a recent and comprehensive study by Kahleova et al., which studied 50,660 adult members of churches in the USA and Canada, it was found that eating one or two meals a day caused lower weight than eating three meals, and also a relatively lower body-mass index (BMI) which got even lower as overnight fasts got longer [4]. The authors state that the positive effects of such a diet are caused by a combination of timing, meal frequency, and overnight fasting, as well as having less frequent meals coupled with precise timing. These results indicate that eating one or two meals is better than eating three or more.

The Prophet’s example

The Prophet Muhammad’s, peace be upon him, recommendations and behaviors lend support to modern medical studies in the area of nutrition, as in many others. He would eat no more than two meals and ensure that one of the meals should consist of light food (such as dates). The Prophet recommended that dinner be eaten, even if it was only a small meal. “Do not leave dinner, even if it is only a handful of dates, because abandoning it makes one weak” (Sunan Ibn Majah).

He defined dinner as the second and last meal of the day, and that it should be eaten after dusk or immediately after the evening prayer.

The Prophet set so many examples about nutrition. He highlighted the dangers of obesity, stating that “What I fear most about my community are developing a belly, oversleeping and idling.” This was centuries ago; nowadays, obesity is an epidemic raging across the world, and its prevalence has almost doubled in more than 70 countries since 1980. In 2015, a total of 107.7 million children and 603.7 million adults were obese [5]. Seventy-five percent of the world’s population is overweight. Obesity, along with dyslipidemia and hypertension, is one of the major factors in cardiovascular diseases. Studies have shown that exercise, as well as meal timing and frequency, are quite effective in weight control [6].

As for table manners, the Prophet said, “The human does not fill any container that is worse than his stomach,” and, “It is sufficient for the son of Adam to eat what will support his back.” Throughout his 63-year-long life, the Prophet never left the table on a full stomach or ate before getting hungry; he recommended that food should not be swallowed without chewing, a practice he maintained. By refusing to sit at tables where there were several types of food, our Prophet was occasionally unable to find anything to eat. There is also no information that our Prophet ever had lunch.

The Prophet’s insistence on fewer meals looks very wise. Not only does eating fewer meals lead to lower incidences of obesity; if it includes a reduction in carbohydrate intake, it can also lead to decreases in total and LDL (bad) cholesterol levels [7]. Considering meal frequency and timing, it is crucial which meals are maintained. In general, breakfast-eaters tend to run a lower risk of weight gain than non-breakfast-eaters – and a significantly lower risk of heart disease [4].

Current studies indicate that food content has as much impact on blood lipids and insulin as meal frequency. Although we cannot fully explain the effects of a single factor on physical health, we are pretty much sure that meal frequencies are closely related to meal timing and which kind of foods are eaten.

The Prophet’s main requirement of food was that it should be lawful and clean, as well as beneficial for the body. His two meals consisted of breakfast and dinner, as is recommended by modern medicine. In a nutshell, the amount of intake and eating etiquette recommended by our Prophet is allocating “one third of the stomach for food, one-third for drink, and one-third for air” (Tirmidhi, Zuhd, 47) and completing meals without getting full. Increasingly, science suggests this may have been good advice!

References

1. Flandrin, J.-L.; Montanari, M. Storia dell’alimentazione; Laterza: Bari, Italy, 2003. 2.Affinita, A.; Catalani, L.; Cecchetto, G.; De Lorenzo, G.; Dilillo, D.; Donegani, G.; Fransos, L.; Lucidi, F.; Mameli, C.; Manna, E.; et al. Breakfast: A multidisciplinary approach. Ital. J. Pediatr. 2013, 39, 44.
2. Potter, C.; Griggs, R.L.; Brunstrom, J.M.; Rogers, P.J. Breaking the fast: Meal patterns and beliefs about healthy eating style are associated with adherence to intermittent fasting diets. Appetite 2018, 133, 32–39.
3. Kahleova, H.; Lloren, J.I.; Mashchak, A.; Hill, M.; Fraser, G.E. Meal frequency and timing are associated with changes in body mass index in adventist health study 2. J. Nutr. 2017, 147, 1722–1728
4. Collaborators, G.B.D.O.; Afshin, A.; Forouzanfar, M.H.; Reitsma, M.B.; Sur, P.; Estep, K.; Lee, A.; Marczak, L.; Mokdad, A.H.; Moradi-Lakeh, M.; et al. Health effects of overweight and obesity in 195 countries over 25 years. N. Engl. J. Med. 2017, 377, 13–27.
5. Paoli, A.; Moro, T.; Marcolin, G.; Neri, M.; Bianco, A.; Palma, A.; Grimaldi, K. High-intensity interval resistance training (hirt) influences resting energy expenditure and respiratory ratio in non-dieting individuals. J. Transl. Med. 2012, 10, 237.
6. McGrath, S.A.; Gibney, M.J. The effects of altered frequency of eating on plasma lipids in free-living healthy males on normal self-selected diets. Eur. J. Clin. Nutr. 1994, 48, 402–407.

Radiation, which refers to emissions of light or particles, is a type of energy transfer. Radiation takes place at any given moment in the environment or the body. Among sources of radiation to which humans are exposed daily are sun rays, radio waves coming from devices such as mobile phones and TV sets, appliances such as ovens or irons that emit heat, and medical machines such as ultrasounds. The radiation emitted from devices and machines do not cause ionization. Ionizing radiation is made up of high-energy wavelengths or particles, and this is the kind of radiation we get from x-ray, CT, and nuclear imaging. This is used to penetrate tissue to reveal the body’s internal organs and structures. Ionizing radiation can damage DNA, and when our cells cannot fully repair the damage, this may result in DNA mutations.[1] The radiation which poses real danger to humans and has the power to ionize is when radioactive—or unstable—atoms decay and emit alpha (α), beta (β), and gamma (γ) rays.

The earth, air, water, and all living things are more or less radioactive because radioactive atoms are everywhere. The average person is annually exposed to radiation levels of 2.6 – 10 mSv (millisievert), which is not that alarming. The maximum limit recommended for people exposed to radiation for occupational reasons is 100 mSv. The lungs of a person who smokes one pack of cigarettes a day are exposed to an annual radiation of 106 mSv.

How can we protect ourselves?

It is recommended by the World Health Organization that children younger than 16 should not use mobile phones; when they do, their calls should not exceed 10 minutes. When purchasing devices, you should also take into account its SAR (Specific Absorption Rate). Prefer devices with a SAR<1 W/kg. It is also recommended to unplug electrical devices when you are not using them, to keep electrical appliances as far away from your head as possible, use the hairdryer for short periods and in intervals, and to avoid using mobile phones for long conversations (or use headphones!).

It’s also worth reconsidering whether using radiation-emitting devices such as mammography, x-rays, or ultrasounds are absolutely necessary. In 2010, the British Department of Health and Social Care banned using tomography for screening purposes. Another study in the US found that one in ten people are exposed to high levels of radiation because of medical tests.

The average radiation rates (mSv) a person was exposed to during use of certain imaging devices is as follows:

Researchers also found that employees in nuclear power plants were exposed to amounts of radiation that far exceeded allowable amounts.

Beware of radon

The natural radiation humans are exposed to most is the gas radon. Some matter with radioactive atoms such as uranium and thorium – both present in the earth since its birth – emit radon, which seeps through the earth and into the walls of houses and through gaps in plumbing. It is recommended to air houses at least 15 minutes every 24 hours as the only way to be protected from radon.

The resistance of living things

Creatures have been created with different forms of resistance to the elements, including radiation. For example, dogs have a lower resistance than humans, while many other creatures such as rabbits, tortoises, and fruit flies have a higher resistance. And then there is the cockroach, which can survive even a nuclear attack. The lethal radiation dose for cockroaches is an incredible 670- 1000 Sv, whereas it is 6-8 Sv for humans.

Scorpions are also much more radiation-resistant than humans. They can withstand up to 1500 Sv, an amount that is 250 times the maximum dose humans can take. Studies have found a correlation between the strength of a scorpion’s venom and their resistance to radiation. The greater the amount of venom, the greater the resistance they have. The presence of the neural transmitter serotonin supports this view.

Are humans radioactive too?

Humans contain trace amounts of radioactive atoms, namely uranium (²³⁸U), potassium (⁴⁰K), and carbon (¹⁴C). An 80 kg human has natural radiation of 8000 becquerel every second, which is equal to 100Bq per kilogram. This amount is not high enough to cause any worry. The human body has 40 trillion cells on average, and every cell has about 100 trillion atoms. The proportion of the radiating atoms in the body is about 8000/4×10²¹.

Precision protection

The radioactive atoms in the body with the highest probability for carcinogenic effects are potassium (⁴⁰K) and carbon (¹⁴C) atoms. The decomposition that leads to cancer stems from mutations in genes, but the molecules that are the building blocks of genes do not have potassium atoms. The likelihood that a cell gets harmed is very low: it is necessary that the particles emitted from the radioactive potassium atom crash into the DNA molecule and harm it, which is as unlikely as threading a needle when blindfolded. The DNA is precisely protected inside the nucleus located at the center of the cell. If we consider the fact that the average diameter of a cell is about 10 microns (1 micron is one-thousandth of a millimeter), we can better appreciate how little space DNA occupies.

Radiocarbon atoms (¹⁴C), on the other hand, might be present in DNA molecules, and they are more dangerous because the emitted particles are more likely to find the target despite having weaker radioactive properties than potassium. A radioactive carbon atom turns into a nitrogen (¹⁴N) atom and may thus cause a chemical change in the DNA. In other words, the carbon atom is possibly to blame for the unexpected development of cancer.

The likelihood of harmful radioactive particles hitting a person’s DNA is low, and the protective system provided for it lowers the likelihood of developing cancer even more. New DNA molecules that form during DNA coupling are repeatedly checked by inspector enzymes. If there is an error, it is detected and then corrected. The broken code is taken out to be replaced with the correct version. Meanwhile, all these steps are checked by other enzymes assigned to the task. More errors might be made in the newly produced DNA molecule because of external factors. Yet ribosomes in the cell start to produce repair enzymes, as per the instructions from the DNA.

When thinking about all the protective factors that have been coded into the DNA for our survival against the 8000 radioactive activities that occur in our body every second, one cannot help but feel awe for the infinite mercy and wisdom that operate in our lives.

References

• http://time.com/5069317/california-mobile-phone-radiation/
• https://www.health.harvard.edu/cancer/radiation-risk-from-medical-imaging
• Choppin, G. et al., Radiochemistry and Nuclear Chemistry, Oxford: Elsevier Science & Technology, 1995.
• www.physics.isu.edu/radinf/natural.htm

[1] https://www.health.harvard.edu/cancer/radiation-risk-from-medical-imaging

Can a person live without sleep?

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.

How much sleep does a healthy person need?

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.

What are the consequences of too much or too little sleep?

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.

What kind of relationship is there between the amount of sleep and rest?

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.

What should be done to enjoy quality sleep?

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.

During which hours should we sleep?

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.

Note

1. Abu Dawud, Jihad, 85; Tirmidhi, Buyu, 6.

References

• Nursi, S., The Flashes Collection, Sozler Publications, Istanbul: 1995.
• Kaynak, H., Uyku (Sleep), Turk Uyku Arastirmalari Dernegi (Turkish Sleep Research Society), http://www.tsrs.org.tr/
• Burns, K., MH, ND, “Studies Show Fajr Prayer is Healthy,” http://www.islamonline.net/
• “Sleep, Blessed Sleep,” http://media.wiley.com/