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Fasting—The Astonishing Physical And Spiritual Benefits

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When you’ve been fasting for twelve hours, your body enters a stage called ketosis.[i] During this time, stored fat begins to be tapped by the liver in order to produce ketones, an alternative to glucose. Even in the resting state, the brain claims more than half of glucose usage. In this way, ketones are an effective way of using stored fats when the body is triggered to produce them, even before activity is added to lifestyle.[ii] And, because of the fat-burning, hormonal, and metabolic shifts that facilitate ketosis within the body’s systems, the metabolic rate increases considerably during this time. Additionally, because ketones offer minimal inflammatory byproducts in comparison to glucose, the brain operates better on them, which is why increased cognitive lucidity often accompanies low-carb diets and intermittent fasts. At the eighteen-hour mark of fasting, ketone production increases to the point that these agents begin to act as hormone-like communicators throughout the body, alerting systems to take such measures as to “reduce inflammation and repair damaged DNA for example.”[iii]

By the twenty-four-hour mark of fasting, the previously mentioned stage of autophagy has initiated.[iv] As cells and tissues are rejuvenated and replaced with newer, healthier cells, immunity is increased and mental clarity continues to improve as a result of operating off ketones rather than glucose. Since growth hormone is secreted as a byproduct of ghrelin, the hunger-sensing hormone, an increasingly insatiate appetite over this moderate period of time lends to the increase of this beneficial hormone, which encourages lean tissue health, boosts cardiovascular health, and diminishes fat accumulation and storage. By the time you have been fasting for forty-eight hours, your “growth hormone level is up to five time as high” as it was before you started the fast.[v] When you’ve been food-deprived for fifty-four hours, insulin will be nearing a type of “reset” point, meaning that the body has adapted its insulin process to become more insulin-sensitive, and thus less insulin-resistant.[vi] This helps decrease inflammation, along with arming your system with protective measures against such ailments as chronic disease, diabetes, and even cancer.

At the seventy-two-hour mark, autophagy hits an all-new level. On a cellular plain, IGF-1 (insulin-like growth factor 1) and PKA (protein kinase A) activity subsides. These two agents assure the life and growth of individual cells—regardless of their health—and thus inhibit autophagy. Considering that these elements exist to ensure that individual cells thrive, their inhibition may sound counterproductive, until we factor in the idea that these elements promote growth, division, and reproduction even in unhealthy, degenerate, or maladaptive cells. “PKA is the key gene that needs to shut down in order for…stem cells to switch into regenerative mode,” and, IGF-1 is a “growth-factor hormone…linked to aging, tumor progression and cancer risk.”[vii] By depriving the body of food for a prolonged time, these agents are subdued; thus, individual cellular survival is forfeited for the sake of overall, uniform cellular health throughout the entire body.

During moderate to advanced stages of autophagy (when the body has fasted for seventy-two hours or more), your body additionally begins the miraculous process of replacing cells within the immune system. Not only are dead and degenerate cells throughout the rest of the body being replaced with newer, healthier ones, but immune cells are actually undergoing the process as well. This springs from the fact that stem cells are renewed and white blood cells flourish, something many studies have linked to being beneficial for those who have recently undergone or are still undergoing chemotherapy. While chemotherapy has long been regarded as a lifesaving tool for many patients, doctors also acknowledge the wreckage it places on the immune system. However, “prolonged fasting for 72 hours has been shown to preserve healthy white blood cell or lymphocyte counts in patients undergoing chemotherapy.”[viii]

So, how does autophagy rejuvenate the immune system? “White blood cells, also known as leukocytes, are the cells which the immune system uses to fight against foreign invaders like viruses and bad bacteria.”[ix] When we experience moderate periods of food deprivation, studies show that the hematopoietic stem cell system—a vital element of the immune system that is responsible for the health of blood and immune cells, but which is diminished in immunocompromised patients, such as those undergoing chemotherapy—hits a sort of reset button.[x] Studies with mice have shown that this process “has implications for chemotherapy tolerance and for those with a wide range of immune system deficiencies, including autoimmunity disorders.”[xi] This means that not only does the body have the potential to overcome current illness, but the system with the ability to prepare for and ward off future sickness is rearmed, having been given a complete overhaul.

When the body has fulfilled a seventy-two-hour fast, old, dead, dying, or degenerate tissues are being broken down and absorbed—replaced with fresh, healthier material. The immune system has been cleaned and rejuvenated. The entire physiology is cleansed, refreshed, and ready to defend against incoming agents of destruction; insulin sensitivity v. resistance is more balanced; metabolic rate is reset at a higher (faster) level; and the cognitive abilities of the mind are revitalized.

A quick Google search of the subject of healing while fasting renders hundreds of stories claiming miraculous healing during such an endeavor. I (Joe) prayed many times with a friend who went through a very difficult season after being diagnosed with a terminal brain tumor. After following an intermittent fasting regime that spanned more than two years, he announced that his body had “eaten” the tumor he had been battling. I’m certainly not claiming that everyone who practices intermittent fasting will experience a reversal of this magnitude, but I am saying that all levels of healing become possible when we submit, 100 percent, to all measures of healthy practices in our ardent search for God’s will.

Jesus’ Fasting

In religious circles, fasting is a period designated for complete or partial abstinence from food or other nutrients to appeal to God in a prayerful way. We see in Matthew 4 that, after He was baptized, Jesus was led by the Holy Spirit into the wilderness in order to fast for forty days and nights. Toward the end of this time, the devil tempted Him by exploiting His bodily desires, testing His level of authority, and even challenging His identity as the Son of God. After Jesus resisted the devil’s persuasions, angels nourished Him (Matthew 4:11). He had fasted for an unprecedented length of time while facing these temptations. However, during His conversation with Satan, Jesus continually refuted the wiles of His foe by referring to Scripture, beginning His rebuttals with, “It is written…” (Matthew 4: 4, 7). In this way, Jesus set the example for us: In our ultimate weakness (in His case, having gone forty days with no nutrition), our strength and healing are found in the Lord. While fasting may, at times, make us feel as though our flesh is being weakened, our spirit gains strength when we deprive our flesh of its needs. Fasting isn’t only a medically beneficial practice, but, as stated in Timebomb, it’s a spiritual strengthener as well:

[Scripture tells us not to be] given to our fleshly desires, but…[to transcend] to a place where we look to Him to meet our needs. The desires of the flesh are often misconstrued as being merely sexual, but this isn’t always true. The desires of the flesh include anything finite that keeps us from following the will of God. When we are fatigued, sluggish, or ineffective, our discernment cannot be sharpened. To truly surrender to the will of God is to follow Him in all our ways. Especially in light of the knowledge that many of us are biologically addicted to food, this heightens the alarm that our food is a combatant that we must arm ourselves against.[xii]

The ironic thing about this is that, across the centuries since these passages were written, mankind has had a spiritual understanding of the stronghold of gluttony and the supernatural, deliverance-rendering power of fasting. However, only recently has science shown how making sacrifices of fleshly satisfaction can bring about healing on a medical level. These principles are confirmed by studies indicating that fasting rejuvenates every part of the body, clearing the mind of chemical inhibitors that slow cognitive ability while revitalizing the immune system, blood, organs, and other tissues by cleansing them of old, degenerate cells and supplying them with fresh, healthy ones.

It is also stated throughout Scripture that God expects us to fast:

“Therefore also now,” saith the Lord, “turn ye even to me with all your heart, with fasting, and weeping, and with mourning.” (Joel 2:12)

In the same way the body moves into a type of self-preservation mode when fasting, operating to rejuvenate and safeguard the body with a sense of urgency, the spirit, likewise, adopts a senses of determination when we fast. We are aware that, during a fast, the cellular level of the body is engaged in a type of preparation-preservation. It’s interesting that fasting is a way of bringing the physical body into the same heightened spiritual plane of rejuvenation and rebirth that the mind enters while the flesh is being denied:

Fasting is calculated to bring a note of urgency and importunity to our praying, and to give force to our pleading in the court of heaven. The man who prays with fasting is giving heaven notice that he is truly in earnest.… He is using a means that God has chosen to make his voice be heard on high.[xiii]



Word of Caution

Intermittent fasting can be confused for a diet, since many people lose weight over the course of its practice, but it’s really more about adopting a nutritional pattern than it is about ruling out certain foods while promoting others. With all this discussion of the health benefits that occur around the seventy-two-hour mark of fasting, you may be thinking that we’re proposing that you immediately stop eating for at least three days.

That is not what we’re suggesting.

In some circumstances, you should not attempt to fast without consulting a natural healthcare practitioner for guidance. Some who suffer medical conditions such as diabetes, poor blood-sugar regulation, or blood-pressure issues; who are severely underweight or have ever struggled with eating disorder;, who are pregnant, breastfeeding, attempting to conceive, or struggling with irregular menstrual cycles; or who are on regular prescription medications may be told that they should either avoid fasting altogether or engage in short durations of deprivation at most.

While the health benefits of moderate to prolonged fasting periods are certainly appealing, those with doubts of any kind regarding their medical response to the practice should seek the advice of a professional.

Additionally, fasting is a practice that takes practice. Sound redundant? That’s because it’s necessary to stress that the seventy-two-hour fast is a goal we must work up to. Many may believe that they’re “tough enough” to take it on in one swoop, but they may be unaware of certain nutritional deficiencies that could cause a sudden attempt at such a long fast to be dangerous. The body needs time to adjust to such practices. With this said, for those who do decide to consider fasting, allow us to give some thoughts on how to initiate the habit.

How To Go About It

First of all, as stated, if you have a medical condition that could compromise your health when fasting, it’s vital that you consult a natural healthcare professional. As mentioned, some who fast regularly may declare that they do so for days on end, which can be intimidating to those who are considering it for the first time. Important to remember is to ease into it, slowly. For example, if you’re used to eating all hours of the day and night, your first step could be to take on a 12:12 (twelve-hour by twelve-hour) fasting schedule. This means that for twelve hours of the day, you’ll refrain from food intake of any kind. So, if you eat breakfast at 8 a.m., then you should eat nothing after 8 pm.

It is generally accepted that coffee, green tea, and lemon/lime water are permissible during a fast, as long as you consume them in moderation. I (Joe) have found that green tea in particular helps tremendously with feelings of weakness or hunger during extended fasts. Herbal teas containing any fruit are not allowed, as many contain sugar that spikes insulin and ends the fast. You can drink water with healthy salt to keep the adrenal glands healthy during this time.

Once you’ve become accustomed to this schedule, you can transfer to a 14:10 regimen, meaning that all your eating must take place within a ten-hour period of each day. So, a breakfast at 8 a.m. will bring a dinner conclusion at 6 p.m. As you adapt to this, you can kick it up a notch by implementing a sixteen-hour fast (16:8). You can do this by eating an early dinner, followed by a late breakfast the next morning. This will be fairly simple, because it’s likely that you’ll be asleep for a large part of the fast. When you’ve had success at this, begin to implement your fasting twice a week. On one of the two days each week, narrow the eating hours on the day before a sixteen-hour fast, until you can convert it to a twenty-four-hour duration. After mastering this, work on the second sixteen-hour fast each week, until the practice has become two periods of twenty-four hours per week (from dinner that first day to dinner on the second day).

Eventually, you can take on the habit of eating an even earlier dinner on the day before a twenty-four-hour fast, followed by a later breakfast on the day following, which extends this period to thirty-six hours. As you continue to reduce your eating hours before or after the fast, the window of time you won’t be consuming anything will eventually stretch to seventy-two hours. However, as stated already, a don’t attempt to fast this long until you’ve have become thoroughly acquainted with how fasting impacts your body.

After the seventy-two-hour mark, additional health benefits occur and are worth looking into for anyone wishing to pursue more intense fasting. However, we’re more interested in helping you reach a realistic level, which will benefit those who are struggling with illness or looking to boost overall health. For that reason, we won’t discuss fasting longer than the three-day duration.

Another important—and commonly overlooked—element of fasting is re-introducing food into the system. Many people, motivated by elevated hunger sustained over a long period of time, follow a fast by succumbing to the seduction of overeating, indulging in gratuitous simple carbs, or even taking in toxic foods, presuming them to be justified in wake of their recent sacrifice for better health. Not only is this counterproductive, but it also throws off the system off as it reacclimates to the higher level of nutritional intake.

The food eaten at the end of a fast should be healthy, balanced, and organic. The diet should include complex carbohydrates (preferably from vegetables) in balance with proteins. When reintroducing food to the system, enteroendocrine cells in the gut release GLP1 (glucagon-like peptide 1) into the blood, which keep insulin balanced as the body readjusts to the nutritional intake.[xiv] If this influx is restored at a slow and steady pace, rather than in a spiking surge, GLP1 will remain in balance so it can then enter the brain’s chemistry and help maintain improved cognitive function and insulin management by “act[ing] directly on neurons to promote synaptic plasticity, enhance cognition and bolster cellular stress resistance.”[xv]

By spending time and effort on recreating your eating patterns, you’ll likely more carefully scrutinize what you eat as well. After all, to take such ownership of your diet will inspire you to ramp up the quality of what you’re eating as well. We’ll discuss how to go about that in an upcoming chapter.

How Long? That’s Between You and God

Ultimately, when, how often, and the length of your fast are completely between you and God. We simply want to make you aware of the vast spiritual and physical benefits of adopting the practice. Further, the correlation between the seventy-two-hour mark and myriad seemingly miraculous health profits becomes our motivation for encouraging those who are physically able to fast to do so. However, we also understand that many readers may have complicated health issues that keep them from being able to fast that long.

If other health issues do prevent you from such an extreme fast, you have other options. For example, you might be able to miss one meal at a time, or you might choose one item to abstain from—such as coffee or a particular snack. Similarly, a modified version of intermittent fasting is known as the 5:2 method, wherein you can consume “500–600 calories on two non-consecutive days of the week, but eat normally the other 5 days.”[xvi] This may be a good option for those whose doctors have warned against fasting altogether.

Even if you’re unable to engage in long-term fasting, we want to encourage you by saying this: Any effort you make will be seen and honored by God.

UP NEXT: The Other Super Key—A Good Night’s Sleep





[iii] Ibid.

[iv] Ibid.

[v] Ibid.

[vi] Ibid.

[vii] Wu, “Fasting Triggers,” Retrieved April 24, 2020.

[viii] Jarreau, “The 5 Stages,” Retrieved April 24, 2020.

[ix] Huang, Sabrina. “Fasting for 72 Hours Can Regenerate the Entire Immune System.” Six Senses Healing Online. January 11, 2019. Retrieved April 24, 2020.

[x] Wu, “Fasting Triggers.” Retrieved April 24, 2020.

[xi] Ibid.

[xii] Horn & Anderson, Timebomb. Pg. 210.

[xiii] Arthur Wallis, God’s Chosen Fast. (Christian Literature Crusade: Fort Washington, PA, 1968), Pg. 42.

[xiv] Jarreau, “The 5 Stages.” Retrieved April 24, 2020.

[xv] Ibid.

[xvi] Gunnars, Kris. “Intermittent Fasting 101—The Ultimate Beginner’s Guide.” Healthline Online. April 20, 2020.Retrieved April 24, 2020.

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