Listen to your body during workouts. If you get light headed, make sure you are consuming enough water. If you notice a significant drop in performance, make sure you are eating enough calories (especially fats and protein) during your feasting window. And if you feel severely “off,” pause your workout. Give yourself permission to EASE into intermittent fasting and fasted workouts. This is especially true if you are an endurance athlete.

"If you’ve never fasted before, be aware that in the early stages you may get dizzy and have headaches. This is part of the body’s cleansing process and will pass with time. Be sure that you break the fast gradually with fresh fruit and vegetables. Do not overeat after the fast. Chili and pizza may sound good after several days of not eating, but please, exercise a little restraint and say no!” – What Christians Need to Know about Fasting by Sam Storms
It can level up your brain, including positively counteracting conditions like Parkinson’s, Alzheimer’s, and dementia. As explained here in this TEDx talk by Mark Mattson, Professor at Johns Hopkins University and Chief of the Laboratory of Neurosciences at the National Institute on Aging fasting is grounded in serious research and more studies are coming out showing the benefits:
I asked him what happened after he stopped fasting. He laughed and said, "I am still very clear on these things, but there's also a time after I end fasting that the whole world seems more vivid and more colorful than ever before. I can distinguish tastes again. The sky seems bluer than before. The air seems crisper in the mountains. All of my senses seem to be heightened toward what is God's creation-which is always good- and what is man's invention-which very often has an element of evil to it."
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“…a progression should be observed in your fasting, especially if this discipline is new to you and you are unfamiliar with its physical effects. Don’t start out with a weeklong water fast! Begin by skipping one meal each day for two to three days and setting aside the money it would have cost to give to the poor. Spend the time praying that you would have used for eating."
Mattson points out that, from an evolutionary perspective, the brain power that fasting generates makes sense. Mammals typically go days without food, often hunting on an empty belly. Semi-starved animals with enhanced smarts and energy would be more likely to obtain food and live another day. “If you are that wolf or lion, now a week with no food, you better be able to focus your mind and concentrate on what you need to do to get food,” he says.
A randomized controlled trial that followed 100 obese individuals for one year did not find intermittent fasting to be more effective than daily calorie restriction. [6] For the 6-month weight loss phase, subjects were either placed on an alternating day fast (alternating days of one meal of 25% of baseline calories versus 125% of baseline calories divided over three meals) or daily calorie restriction (75% of baseline calories divided over three meals) following the American Heart Association guidelines. After 6 months, calorie levels were increased by 25% in both groups with a goal of weight maintenance. Participant characteristics of the groups were similar; mostly women and generally healthy. The trial examined weight changes, compliance rates, and cardiovascular risk factors. Their findings when comparing the two groups:
A fast for God doesn't have to be all day. It can be one meal. You could choose to give up sugar or caffeine. Fasting for God is sacrificing something that is important to you. Surrendering to God means giving of yourself for Him. We cry out, "All of you, none of me." Fasting tears down strongholds, fasting causes divine power to loose the chains of injustice and sets the captive free. A fast for God ushers in every ministering spirit to go forth on your behalf bringing solutions to every problem. If you want to see God's power working in your life, then fast.
If you keep fast, to count everyday pledge yourself you will act honest, sincere, controls your desires, mediate. This is a way how you make yourself free of five thieves: "On the ninth day(naomi) of the month, make a vow to speak the Truth, and your sexual desire, anger and desire shall be eaten up. On the tenth day, regulate your ten doors; on the eleventh day, know that the Lord is One. On the twelfth day, the five thieves are subdued, and then, O Nanak, the mind is pleased and appeased. Observe such a fast as this, O Pandit, O religious scholar; of what use are all the other teachings? ||2||" (Guru Granth Sahib Ji, Ang 1245)
Finally, fasting was frequently associated with supplicatory prayer. David prayed and fasted over his sick child ( 2 Sam 12:16 ), weeping before the Lord in earnest intercession (vv. 21-22). Nehemiah, having heard of Jerusalem's desolation, wept, fasted, and prayed that God would give him favor with King Artaxerxes of Persia so that he might return to his homeland and repair its ruins ( Neh 1:4-11 ). Esther, under similar circumstances, urged Mordecai and the Jews to fast for her as she planned to appear before her husband the king ( Esther 4:16 ). Clearly, fasting and petition are here one and the same (cf. Jer 14:12 ).
Another type of intermittent fasting, alternate day fasting has you severely restricting the amount of calories you eat during fasting days, then eating to your stomach’s content on non-fasting days. Food isn’t completely off the table, but you’ll stick to about 25 percent of your normal caloric intake. Someone eating 2,000 calories would cut back to 500, for example. Alternate-day fasting isn’t necessarily a long-term plan, because it can become difficult to stick to, but it can be helpful to get a healthy habit in motion.
As researchers study the different fasting mechanisms to try to determine the ideal protocol for a variety of outcomes in a variety of populations, however, the general public must proceed by trial and error. That leaves dietitians such as myself concerned that the hype around fasting could encourage people to follow harmful plans that severely restrict nutrients, cause stress or unsuccessfully treat serious conditions.

The increase in longevity is also clearly associated with a decrease in disease states that would cut your life short, and calorie restriction is associated with a number of health improvements, including reduced visceral fat, reduced inflammation, lower blood pressure, and improved insulin sensitivity,5,6 just to name a few. Earlier research has demonstrated that calorie restriction helps extend the lifespan of animals by improving insulin sensitivity and inhibiting the mTOR pathway.
There is no long-term fasting research yet, but the benefits are promising and the risks low: You can always just quit. A limited-time fast might bump you off a plateau or out of a rut, says Keri Glassman, R.D., who advised our fasters during their diets, though she says that for some, fasting, even short-term, may be too rigid. That hints at the larger takeaway: Perhaps more than for traditional diets, these plans won't work for everyone.
Jimmy Kimmel lost 25 pounds on the 5:2 diet, eating fewer than 500 calories on Mondays and Thursdays then eating whatever he wants the rest of the week. Actor Benedict  Cumberbatch also lost on the 5:2 diet while Hugh Jackman had a different intermittent fasting schedule. Each day he ate during an eight hour period but fasted for the remaining 16 hours. Is this just a Hollywood fad or are there real benefits to intermittent fasting?
Those fasting may experience side effects of fatigue, malaise, aches and pains, emotional duress, acne, headaches, allergies, swelling, vomiting, bad breath, and symptoms of colds and flu. These reactions are sometimes called healing crises, which are caused by temporarily increased levels of toxins in the body due to elimination and cleansing. Lower energy levels should be expected during a fast.
Additionally, various studies ( in both animals and humans) have shown that intermittent fasting could be an effective way for losing weight, especially belly fat, as it may slightly boost your metabolism while helping you consume fewer calories. The diet plan may also boost digestion and reduce bloating, as well as improve mental clarity. One of the best things about IF is that it may help those who tend to overeat with late-night snacking as fasting can reduce hunger, helping you stick to your diet plan.
Lowers insulin levels: Intermittent fasting acts on insulin in two ways. First, it boosts your adiponectin levels, which helps restore insulin sensitivity to prevent weight gain and diabetes. Second, fasting decreases your fasting insulin levels. Lowered insulin is the cue your body needs to make the switch to burning stored fat instead of glucose.[7]
Because it simplifies your day. Rather than having to prepare, pack, eat, and time your meals every 2-3 hours, you simply skip a meal or two and only worry about eating food in your eating window. It’s one less decision you have to make every day. It could allow you to enjoy bigger portioned meals (thus making your tastebuds and stomach satiated) and STILL eat fewer calories on average.

On the other five days of the week, there's no calorie cap, and no food is off-limits. This freedom isn't permission to binge and make up for your two fast days, but it does mean you shouldn't feel guilty about eating a slice of cake. U.S. News experts evaluate the Fast Diet poorly in all rankings, mostly due to its tough-to-follow nature and health risks in some populations.


If you're worried you’ll be starving while fasting, you’ll be pleasantly surprised! Intermittent fasting decreases your hunger hormone ghrelin, which in turn can increase dopamine levels in the brain. (Just another example of the gut-brain axis at work.) Fasting can also help free people from emotional eating and kill cravings by transitioning your metabolism from unstable sugar-burning to steady fat-burning.
In order for a fast for God to be effective, you must also pray. Praying and fasting to God is a powerful weapon against adversity. Joel 1:14 says, "Declare a holy fast; call a sacred assembly. Summon the elders and all who live in the land to the house of the Lord your God, and cry out to the Lord." A fast for God puts your trust in Him as the only one who can help you. During your fast for God, remember that He is faithful and true, willing and able to help you in any way He can.
On my fasting days, I would wake up, have coffee, and start my day without any food. This would continue until about 5:30 p.m., when I would prepare a dinner that didn’t vary from my regular dinner in terms of either what or how much I ate. So, my fasting dinner would be something normal for me, like stir-fry, pasta, soup, sandwich, sushi, etc. This dinner looked like any other and occurred at the usual time. This made it simpler — I was just resuming eating with no special fanfare.

I know many of you are itching to get started right away, but IF is not for everyone. It is not recommended for pregnant women, women who are breastfeeding, people with diabetes, or other people who need to closely regulate their blood sugar. In addition, there has not been research on participants who are underweight, very old, or very young (<18 yrs. old) and these populations could be at higher risk for experiencing negative consequences of fasting (Longo and Mattson , 2014). So please:
Autophagy is spring cleaning for your cells. It’s Latin for “self-eating,” which is spot-on: when autophagy turns on, your cells sift through their internal parts, get rid of anything that’s damaged or old, and install shiny new versions.[8] Autophagy is like a tune-up for your car: afterward everything runs more smoothly. It reduces inflammation and even boosts longevity. Intermittent fasting triggers, to quote researchers, “profound” autophagy, especially in your brain.[9]
Fasting is obligatory for every Muslim one month in the year, during Ramadhan. Each day, the fast begins at sun-rise and ends at sunset. During this time Muslims are asked to remember those who are less fortunate than themselves as well as bringing them closer to God. This also helps to give the digestive system a break. Non obligatory fasts are two days a week as well as the middle of the month, as recommended by the Prophet Muhammad.

Classical Pentecostalism does not have set days of abstinence and lent, but individuals in the movement may feel they are being directed by the Holy Spirit to undertake either short or extended fasts. Although Pentecostalism has not classified different types of fasting, certain writers within the movement have done so. Arthur Wallis writes about the "Normal Fast" in which pure water alone is consumed.[75] The "Black Fast" in which nothing, not even water, is consumed is also mentioned. Dr. Curtis Ward points out that undertaking a black fast beyond three days may lead to dehydration, may irreparably damage the kidneys, and result in possible death.[76] He further notes that nowhere in the New Testament is it recorded that anyone ever undertook a black fast beyond three days and that one should follow this biblical guideline. Dr. Herbert Shelton advises that one should drink water according to natural thirst.[77] In addition to the Normal Fast and the Black Fast, some undertake what is referred to as the Daniel Fast (or Partial Fast) in which only one type of food (e.g., fruit or fruit and non-starchy vegetables) is consumed.[75] In a Daniel Fast, meat is almost always avoided, in following the example of Daniel and his friends' refusal to eat the meat of Gentiles, which had been offered to idols and not slaughtered in a kosher manner. In some circles of Pentecostals, the term "fast" is simply used, and the decision to drink water is determined on an individual basis. In other circles profuse amounts of pure water is advised to be consumed during the fasting period to aid the cleansing of internal toxins. Most Pentecostal writers on fasting concur with Dr. Mark Mattson who says that sensible intermittent fasting with a sensible water intake can strengthen the organism and assist thwarting degenerative diseases.[78]


Some of the best evidence on the impact of fasting on bodyweight and fat comes from a December 2018 systematic review. The researchers looked at randomized controlled trials of intermittent fasting and found that the people who fasted lost about 4 to 8 percent of their original bodyweight, on average. So fasting worked, but, interestingly, it didn’t outperform regular, continuous calorie restriction (“eat less every day” dieting), and it didn’t lead to dramatic weight loss.
Scot McKnight is an Anabaptist theologian and is the Karl A. Olsson Professor in Religious Studies at North Park University. The author of more than10 books and numerous articles and chapters in multi-authored works, McKnight specializes in historical Jesus studies as well as the Gospels and the New Testament. As an authority in Jesus studies, McKnight has been frequently consulted by Fox News, WGN, US News & World Report, Newsweek, TIME, as well as newspapers throughout the United States.

The ancient Greek physician Hippocrates wrote, “To eat when you are sick, is to feed your illness”. Another ancient Greek writer and historian Plutarch is also credited with penning “Instead of using medicine, better fast today”. In more recent times one of our founding fathers, Benjamin Franklin, stated, “The best of all medicines is resting and fasting”.


Feelings over hunger may also become more tolerable over time. Studies of alternate-day fasting have shown that people rate their hunger at 8 on a scale of 1 to 10 for their first few fast days, but after two weeks, that number drops to 3. Mattson puts the window at three to four weeks, after which, he says, "you're not hungry on fasting days." (Try clean eating to shed stubborn pounds. This plan gives you 150 delicious recipes you'll love!)
For Roman Catholics, fasting, taken as a technical term, is the reduction of one's intake of food to one full meal (which may not contain meat on Ash Wednesday and Fridays throughout Lent) and two small meals (known liturgically as collations, taken in the morning and the evening), both of which together should not equal the large meal. Eating solid food between meals is not permitted. Fasting is required of the faithful between the ages of 18 and 59 on specified days. Complete abstinence of meat for the day is required of those 14 and older. Partial abstinence prescribes that meat be taken only once during the course of the day. Meat is understood not to include fish or cold-blooded animals.
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