There are many ongoing studies into fasting, a practice prescribed across many religions. Increasingly, there is evidence to support that intermittent fasting is beneficial to human health.

The opposite of fasting – overeating – has been revealed to be a major culprit in many illnesses, including cancer, obesity, and heart disease. For many years, the medical consensus was that fasting, i.e. prolonged hunger, too, could have deleterious effects on the human body. From kidney failure to loss of muscle, fasting was believed to be harmful – thus calling into question the benefits of this widespread religious commandment.

People of faith – including Muslims – have long believed that God wouldn’t recommend a practice that was harmful to the body. The hardships and troubles that accompany a religious practice are not too extreme for people aware of their servitude to God: they regard their trials as a testament of their faith. Part of that faith is the certainty that God wouldn’t recommend a harmful or unbearable practice.

In this article, we will share with you two unknown benefits of fasting that have been recently discovered.

Regenerating stem cells

There is a substantial body of evidence showing that staying hungry during certain periods of the day heals the body’s metabolism, hastens loss of fat, decreases oxidative stress,* and improves the functions of the tissues that make up various organs including the liver, the intestines, and the brain. The first of the two new discoveries about the underlying processes, however, provides a missing piece of the puzzle by helping us understand the incredible changes hunger triggers in stem cells.

Researchers at MIT, Duke University School of Medicine, and Whitehead Institute for Biomedical Research in Cambridge published an article recently on stem cells, indicating that part of stem cell’s mystery could lie in the oxidation (burning) of fat in the mitochondria [1]. Omer H. Yilmaz and his fellow researchers found that a 24-hour fast hastens fat breakdown in intestinal stem and special progenitor cells of rats.

To run the study, Yilmaz and colleagues let the mice go hungry for 24 hours to study the state of their stem cells. They found that the functions of intestinal stem cells increased, and fat metabolism quickened, in both young and aged mice, even during early periods of hunger. They saw that the body’s tapping into fat for its energy needs maintained the health and strength of the intestinal stem cells. Moreover, they noticed that if the aged mice did not fast, they started to lose their ability to break down and use fats for energy expenditure.

The researchers obtained more interesting results as the studies progressed. It was found that a single period of hunger for 24 hours boosted renewal of intestinal cells – and the stem cell functions increased even more significantly in aged mice. Another interesting finding was that mice with damaged intestines that were fasted recovered faster than those that were fed.

“My lab is really interested in understanding how diet, in general, can be used to improve tissue function,” Yilmaz said. “One of the tissue types I study is the intestine. In my lab we study the intestine because it’s one of the largest organs in the body. It’s also a tissue that experiences rapid cellular turnover.” [2]

The intestine is lined by a single layer of cells, Yilmaz explains, that turns over every 5 to 7 days. The workhorses of the intestinal lining and this cellular turnover are intestinal stem cells. These cells must retain a high level of function or cellular health in order to replenish the intestinal epithelium on a regular basis. Intestinal stem cells are particularly important in terms of repairing intestinal damage caused by gut infections and chemotherapy, for example.

The single layer of epithelial cells needs to be renewed every 5-7 days: the aids and enzymes secreted in the intestine for digestive and absorptive activities damage cells despite the protective mucus layer, and some other cells already burst and die as they empty their secretions. Moreover, some medications, particularly chemotherapy, cause the destruction and breakdown of the epithelial cell layer. However, fast-multiplying stem cells replenish the epithelial cells. Stem cells are very active and young and have the ability to divide and multiply continuously.

Dr. Yilmaz also says:

“As we age, stem cells in the intestine as well as in many other tissues of the body, including in the blood and nervous systems, become less functional. We believe that reduced adult stem cell function contributes to some of the decline of function associated with old age. My lab is very interested in studying low-calorie interventions to delay this decline. As a field, we’ve known for over 100 years that low-calorie states such as fasting or caloric restriction can have positive effects on tissue health and aging. We’ve seen evidence that fasting during times of intestinal infections that lead to diarrhea may promote healing of the intestinal lining, for example.” [2]

This quote emphasizes the importance of the issue. Yilmaz adds that despite all this knowledge, the cellular mechanisms of this renewal have not been discovered, and he and his team are working to find out how fasting and hunger enable this recovery.

Stem cells become happy in fat!

The researchers discovered through the experiments that the stem cell function could be brought about in hungry mice by the burning (oxidation) of fatty acids in intestinal cells. When they stopped the fat metabolism through genetic engineering, they noticed that the benefits of fasting on intestinal stem cells were negligent.

In the present dietary conditions, we obtain nearly 60-70% of our energy from carbohydrates or sugar, 20% from fats and 10% from amino acids. Yet an interesting finding revealed by Dr. Yılmaz and his research team is that we essentially obtain much greater energy from using fats once we fast. According to their experiments on mice, during fasting, the intestinal stem cells in both young and aged mice switch from carbohydrates to fats as the primary source of energy, and this shift enables improvement in stem cell functions.

It is not yet known what underlies the fat metabolism that boosts stem cell functions in response to fasting, but it is observed that stem cells work better when they burn fat. The ability to metabolize fats efficiently decreases with age.

It is likely that this hastened metabolism – encouraged by certain diets, like the keto diet, where the amount of fat ingested is raised to 70% and carbohydrate intake is limited to 5% – helps with epileptic seizures and similar neurological disorders: the ketone bodies generated during metabolism of fats are used as energy sources by the brain.

According to Dr. Yilmaz, if fasting can improve the functions of intestinal stem cells through metabolism of fats, the key is the mitochondria, the powerhouses of the cell responsible for this function. Fat metabolism, or the immediate breaking down or “burning” of the fat entering the cell, is carried out in the mitochondria. Disrupted energy generation associated with aging and decreasing mitochondria can be a reason for the brain’s susceptibility to age-related illnesses. Positive developments in brain functions can therefore be viewed in connection with the correlation between fasting and the oxidation of fatty acids.

Cleaning by fasting

Just like the spring cleaning in our homes, our cells need a thorough cleaning to function properly. Wrongly folded protein particles, remains of damaged organelles, broken molecular pieces, and aged cells that can no longer divide should be disposed out of our cellular structure. Fasting perfectly performs the task of cleaning these wastes and clearing the area in the cell.

“Everything has zakat (a means of cleaning), and the zakat of the body is fasting.” (Ibn-i Majah, Siyam: 44)
“Fasting is a protective shield.” (Bukhari, Sawm: 2)

What is autophagy?

Autophagy is the compound of two ancient Greek words: auto (self) and phagos (eating). What is meant by “self-eating,” is the breaking down and recycling of protein waste and old, impaired molecules by intracellular digestive organelles called lysosomes. In this way, proteins or cellular organelles are digested and taken out of circulation. We can liken autophagy to garbage collection.

Japanese researcher Yoshinori Ohsumi’s study, which brought him the 2016 Nobel Prize for Medicine, found that the autophagy that occurs inside the cell due to fasting or starvation plays an important role in preventing ageing, infections, and tumors. If autophagy breaks down, many illnesses may be triggered, including cancer. Conversely, if autophagy activity is regular, tumors may be suppressed – depending on the stage of development and type of tumor. Cancer research has long focused on channeling these autophagic activities. Restriction of food intake through fasting shows promise: it may protect normal cells while triggering autophagy and thus increasing the effect of cancer treatments. Autophagy might offer solutions or treatment options for other illnesses, too, including inflammatory diseases [3], neurodegeneration [4], metabolic and cardiovascular diseases [5], obesity [6], and metabolic disorders.

Preclinical studies have shown that dietary restrictions by fasting contribute to the increase of a person’s lifespan and slow the development of age-related diseases such as cancer and neurodegenerative and cardiovascular diseases [7].

* Oxidative stress: The damage caused as a result of excessive proliferation of free oxygen radicals released from foods that spike blood sugar (with high glycemic index) as metabolic waste. A good example of oxidative stress is the browning of certain foodstuff such as apples, bananas, etc. sometime after they are peeled.

References

1. Yilmaz, Omer H. et al. 2018. “Fasting Activates Fatty Acid Oxidation to Enhance Intestinal Stem Cell Function during Homeostasis and Aging.” Cell Stem Cell, Vol. 22, Issue 5, May 3, pp. 769–778.
2. Paige Brown Jarreau. 2018. “Eating (Or rather, Fasting) Our Way to Rejuvenated Stem Cells?” in Life and Tech @ LifeOmic. June 7. A Medium Corporation.
3. Cadwell K. 2016. “Crosstalk between autophagy and inflammatory signaling pathways: balancing defence and homeostasis.” Nat Rev Immunol.16 (11): 661–75.
4. Menzies FM, Fleming A, Caricasole A, Bento CF, Andrews SP, Ashkenazi A et al. 2017. “Autophagy and Neurodegeneration: Pathogenic Mechanisms and Therapeutic Opportunities.” Neuron. 93 (5):1015–34.
5. Bravo-San Pedro JM, Kroemer G, Galluzzi L. 2017. “Autophagy and Mitophagy in Cardiovascular Disease.” Circ Res. 120((11)):1812–24.
6. Lavallard VJ, Meijer AJ, Codogno P, Gual P. 2012: “Autophagy, signaling and obesity.” Pharmacol Res. 66 (6):513–25.
7. O’Flanagan CH, Smith LA, McDonell SB, Hursting SD. 2017. “When less may be more: calorie restriction and response to cancer therapy.” BMC Med. 15(1):106.

Some medications are effective directly over the area they are applied to. Some however are transported to distant regions via blood flow and that is where they are most effective. Medication is either taken orally or through injection. When medicine passes into the blood stream from the place of administration, it is considered to be absorbed. A good example is the transportation of medicine into the blood stream of capillary vessels between the muscle cells when injected into muscle tissue. A drug taken orally however is absorbed through the blood vessels in the gastro-intestinal system.

For orally-taken medication to be absorbed, it should be able to dissolve in gastro-intestinal fluids. First, it is broken into smaller units due to the corroding effects of stomach acid and various enzymes are secreted, then chemicals in the drug composition pass into the gastro-intestinal fluid in a molecular form. This event resembles the dissolving of a sugar cube inside a glass of hot tea. First, the sugar cube gets broken into pieces and then dissolves. A mix with a tea spoon makes this event happen a little faster. In a similar fashion gastro-intestinal movements help with the absorption of medicine. Liquid drugs like syrups dissolve in the gastro-intestinal fluid faster since they are already in smaller units; therefore they get absorbed faster.

Drugs mostly get absorbed through the small intestine. The most important task of this organ is to enable the absorption of nutrients. It is approximately 10 meters long and 4 centimeters wide. The inner lining of the small intestine has finger-like projections called villus and even smaller projections that are located on these villi are called microvillus. One of the reasons, maybe the most important reason, why the our intestines are created in this way is that as a result, the inner surface area of intestines increases multifold. Such that the inner surface area of a human beings small intestine can increase up to 200 m2 and this greatly facilitates the absorption. These projections are made of intestinal cells.

The molecules carrying the medication reach the capillary vessels by passing through these cells and then join the blood stream by crossing through capillary vessel cells. Furthermore, intestinal cell membranes host a special protein that filters unwanted substances for the cell and returns them back to intestinal lumen. Thus these unwanted substances are excreted out of the body along with other unabsorbed matter. In the same way, some drugs are held by this protein and released back into the lumen thus decreasing absorption rate for drugs experiencing this reaction.

Liver: The organ responsible for eliminating the harmful effects of medication

As soon as medication joins the bloodstream after absorption, it is first transported to the liver. This is because pulmonary veins that collect blood from the intestines are connected primarily to the liver. One of the many functions of the liver is the elimination of harmful substances entering the body. For this reason, absorbed substances are directly sent to the liver. The liver is employed with the task of chemical conversion with these substances that are transported to it. One of the wisdoms behind liver metabolism is to reduce the effects of these harmful substances via these events and to convert them into an excretal material. In the same way, drugs are metabolized in the liver, lose their efficacy and prepare for excretion.

Many drugs interfere with each other’s metabolism. If one drug’s metabolism is inhibited, blood concentration of such chemicals increase and adverse effects of drugs become more frequent. Irresponsible drug use must be avoided for this reason. Drug interactions may lead to major damage in addition to the drug’s individual adverse effects. Moreover different nutrients also affect drug metabolism. For instance, grapefruit inhibits metabolism of certain medicines, as a result blood concentration of these medicines increase and adverse effects can be observed. On the other hand, some nutrients like broccoli, cabbage, and charcoal roasted meat speed up the metabolism of certain medicines. In this case, the blood concentration of the affected drug drops and may lead to reduced benefits from intended use. Because of this reason, patients on long-term medicine treatment should not consume these types of food.

The rest of the drug molecules that escape these metabolisms is directed towards blood vessels feeding other organs. Some drug metabolisms in the liver present individual differences as metabolic levels change from person to person. Thus, a drug with the same dosage develops desired blood concentrations for some people, fails to meet this level for others or can even cause high blood concentrations enough to generate adverse effects in other individuals. That is why a medicine that has benefited a patient should never be used by somebody else without consulting a doctor.

The function of bile

Bile secretion originating from the liver and gall bladder has critical importance in the digestion and absorption of fats. Bile breaks apart fats into small pieces so that digestive enzymes can affect them. As a result of this, absorption is provided for fats and vitamins like A, D, E, K that are soluble in fats. In a similar fashion bile improves solubility and absorption of some drugs that does not dissolve in gastro-intestinal fluid. Another task of bile secretion is the removal of certain substances from the body. Waste materials in the bile that is dumped into duodenum are excreted through the digestive track. Some drugs are excreted in this way.

Drug intake before or after meals

It is a well known practice that medications are advised either to be taken after or before meals. When medications are taken after a meal, they cause less of the possible unwanted disturbances such as stomach sickness, aches or indigestion.

On the other hand, nutrients may reduce intake of certain drugs, therefore they need to be taken before meals. However medications taken right before a meal does not apply in this case since the food will still mix with the medication in the stomach. When taking these medicines, it should at least be an hour before meals. Generally consumption of a medicine before or after a meal does not really change its absorption level. But medications taken before meals pass the stomach into the intestines without delay and therefore get absorbed faster. This practice is important in cases where an immediate effect is desired such as pain relief. Plentiful water intake also helps with faster and improved absorption of drugs.

Some medications are packed into capsules made of gelatin-like substances. Medicines with undesirable taste and smell can be offered in this form for consumption. Moreover, if a drug is harmful to the stomach or gets degraded in stomach acid, then this drug can be prepared in capsules that are durable to stomach acid but soluble in the intestines. That is why consumption of medication without its intended capsule should be avoided. In a similar fashion, some medicinal tablets are designed to deliver its molecular contents particularly to the intestines. These types of medication must be taken as a whole unit. Otherwise it can be ineffective or may lead to harmful reactions.

Delivery of drugs to targeted regions

The molecules carrying medication that join the blood via absorption get dispersed by blood circulation throughout the body. These molecules reach various parts of the system via blood vessels, and then diffuse into organs via capillary vessels. However, their entry to the brain is difficult because this vital organ of the body has a special protection to guard itself from possible harmful effects of various substances that enter the body from the outside. Capillary vessels in the brain are different from other capillary structures in the rest of the body as they are created without an intercellular space in between vessel cells. Furthermore, these cells are bound to each other with their tight connective regions.

These capillaries are surrounded by a thicker membrane compared to other capillary vessels. This membrane is also host to various cells that wrap around the vessel. Therefore, because of these factors and other similar ones, some medications can enter the brain in very limited amounts. Drug molecules can display their targeted effects when they bind to target proteins, called receptors, in the organs. These proteins, which are very unique to each drug, exist on the cell membrane or in the cell. In addition, drug molecules also bind to other receptors that are not specific for them, and this causes adverse effects as a result.

Excretion of drugs from the body

Drugs are excreted from the body via the liver and kidneys. One function of these organs is to filter the blood from foreign substances. It was previously mentioned that absorbed substances from intestines are transported to the liver first where some amount gets metabolized and the remaining amount rejoins blood circulation that feeds other organs. Drug molecules that pass through the liver return back to it repeatedly many times because of continual blood circulation. In each of these arrivals, some amount is again metabolized. Molecules of metabolized drugs are excreted out of the body via the kidneys and through the bile at a limited level.

Only some portion of drug molecules get excreted via the kidneys without being metabolized. This ratio is higher with some medications. These types of medications are considered to be removed only by the kidneys, whereas some other drug types cannot be excreted without getting metabolized through the liver. As previously mentioned, the purpose of drug metabolism is to convert drugs into easily removable forms. If these types of drugs are not metabolized, they are rejoined to the blood circulation after filtration by the kidneys without joining the urine. It is impossible for the liver to sense these happening within the kidneys if it was not that the liver and every cell in it were employed by one authority who created them in the first place. Drug molecules concentrate in the liver and kidneys since these organs are employed with drug removal. As a result harmful effects of drugs are often experienced in these organs. Therefore unnecessary drug use should be avoided, otherwise the health of these organs deteriorate and eventually fail to carry out their basic functions.

As noted above, events that are taking place within many of our organs, stomach and elsewhere like kidneys impact on the journey of drugs in our body, therefore changing its effect. The harmonious creation of our organs that are home to many miraculous events is the major component of the entire process in which causations have their due role only as much as they are allowed by their Creator. As a test for humankind, both illness and the cure is provided by God, the All-Healer. Therefore it is the duty of a patient to see a doctor, take the medication properly and never forget that cure is only provided by the Almighty, without obsessing over causational chains.

References

• Guyton, Arthur C., John E. Hall. 1991. Textbook of Medical Physiology, Saunders.
• Patton, Kevin T., Gary A. Thibodeau. 1993. Anatomy & Physiology, Mosby.
• Rang, Humphrey P., Maureen B. Dale, James M. Ritter. 1999. Pharmacology, Churchill Livingstone.
• Brunton, Laurence, John Lazo, Keith Parker. 2006. The Pharmacological Basis of Therapeutics. McGraw-Hill Professional