This type of fasting is also known as cyclic fasting. Intermittent fasting is a catch-all phrase for eating (and not eating) intermittently. In fact, almost all of the fasting methods below are types of intermittent fasting! Typical intermittent fast times range from 14 to 18 hours. The longest period any one of these plans would require you to abstain from solid food would be about 32–36 hours.
There are a couple of other caveats here. Fasting diets require working through hunger, saying no to the bagels and muffins put out in your morning meeting or the food at your business lunch. So it’s no surprise that many people can’t stick to fasting diets long enough to keep the weight off. In another 2018 review of the literature on fasting’s impact on weight, the researchers note, “Dropout rates have been as high as 40 percent. Thus, despite the statistical significance of weight loss results, the clinical significance and practicality of sustaining an [intermittent fasting] regimen are questionable.”
How It Works: This one’s easy: Eat very little one day, and eat like normal the next. On the low-calorie days, that means one fifth of your normal calorie intake. Using 2,000 or 2,500 calories (for women and men, respectively) as a guide, “fasting” (or “down”) day should be 400 to 500 calories. Followers can use this tool to figure out how many calories to consume on “low-calorie” days.
“I used to crave foods like crazy when I first started,” says Dr. Sylvia Tara, author of The Secret Life of Fat, in a Bulletproof Podcast episode. “after six to eight weeks, I didn’t feel it anymore.” Dr. Tara kept a journal or foods and schedules to find how fasting worked for her. Her advice for weight loss with intermittent fasting? “For people who have those 20 pounds, know, number one, it can be done. Number two, it might be a bit more effort than you thought it was going to be… Third, know that it gets easier with time and you can maintain it. It really isn’t as bad once you get into it, and it’s extraordinarily effective.”
Confront injustice through fasting. Fast as a way of expressing poverty in your body, to show solidarity with those who are impoverished by injustice in our fallen world. Divest yourself of some resources – food – for the good of others. Convert what you give up in food when you fast into gifts for the poor by estimating the cost of the food you would have eaten if you hadn’t fasted and giving that amount to charities that help poor people. Use the time you would have spent eating to serve people in need and help bring more justice to the world. Use your fasting to call attention to other people’s needs, such as when you’re working to find solutions to the problems causing injustice and want to inspire others (like government leaders) to take action as well. However, be sure not to call attention to yourself, simply to try to impress others with your fasting. Use fasting to confront injustices in our own attitudes and behaviors, as well – to break the hold of unhealthy habits in your life and help you grow in holiness. Ask God to give you a clear vision of what He would like your life to look like. Then, through fasting, express your complete surrender to that vision.
Whether a regimen calls for two fasting days a week or eating your meals in a smaller "window" of time in the day, all plans share a near-freedom from calorie counting, a big plus for weary food diarists. Once you have planned your fasting-period menu—say, a 500-calorie day of chicken and veggies—you're set. And in your nonfasting periods, you eat normal, healthy meals (even that steak!) without worrying about every bite.
In addition to our attitudes towards God and our stance before man, our motives must also be correct. We should fast in order to further the building up of God’s kingdom by seeking to minister to others. The prophet Isaiah received from the Lord the acceptable motives for our fasts: “Is not this the kind of fasting I have chosen: to loose the chains of injustice and untie the cords of the yoke, to set the oppressed free and break every yoke? Is it not to share your food with the hungry and to provide the poor wanderer with shelter -- when you see the naked, to clothe him, and not to turn away from your own flesh and blood?” (Isaiah 58:6-7).
Jesus was teaching that after His departure, the entire dynamic would change and the disciples would need a different type of preparation and provision. Fasting was to be a vital part of this new preparation. The new covenant is based on the truth that we have received everything in Christ, “Praise be to the God and Father of our Lord Jesus Christ, who has blessed us in the heavenly realms with every spiritual blessing in Christ” (Ephesians 1:3).
Often, the major argument for periodic caloric restriction is that we did not evolve to eat three meals a day, every day. Some fasting proponents argue that our bodies were designed to be able to run on little or no food for as long as several weeks or even months. After all, we didn’t have access to a steady food supply until the advent of agriculture, and it wasn’t until the neolithic revolution that humans adopted a more regular meal pattern.
^ Cléir, Síle de (5 October 2017). Popular Catholicism in 20th-Century Ireland: Locality, Identity and Culture. Bloomsbury Publishing. p. 101. ISBN 9781350020603. Catherine Bell outlines the details of fasting and abstinence in a historical context, stating that the Advent fast was usually less severe than that carried out in Lent, which originally involved just one meal a day, not to be eaten until after sunset.
In section 106, of the same book, Yudhishthira says, "the disposition (of observing fasts) is seen in all orders of men including the very Mlechchhas..... What is the fruit that is earned in this world by the man that observes fasts?" Bheeshma replies that he had asked Angiras "the very same question that thou has asked me today." The illustrious Angiras says Brahmans and kshatriya should fast for three nights at a stretch is the maximum. A person who fasts on the eight and fourteenth day of the dark fortnight "becomes freed from maladies of all kinds and possessed of great energy."
Improves cholesterol: Intermittent fasting diets impact cholesterol by decreasing your levels of LDL and VLDL cholesterols (the bad stuff). While improving your cholesterol won’t directly lead to weight loss, overweight and obese people are more likely to have dangerously high LDL and VLDL cholesterol, and the cardiovascular risk that comes with it.
Mosley tried this "intermittent fasting" diet when his doctor showed him that though he was only a few pounds overweight, his cholesterol was high and his blood sugar was headed in the wrong direction. He writes that he knew fasting would be difficult, but his hunger pangs passed quicker than he expected. He also felt that fasting sharpened his senses and his brain. Plus, the diet delivered all the results he hoped for.
The second major day of fasting is Tisha B'Av, the day approximately 2500 years ago on which the Babylonians destroyed the first Holy Temple in Jerusalem, as well as on which the Romans destroyed the second Holy Temple in Jerusalem about 2000 years ago, and later after the Bar Kokhba revolt when the Jews were banished from Jerusalem, the day of Tisha B'Av was the one allowed exception. Tisha B'Av ends a three-week mourning period beginning with the fast of the 17th of Tammuz. This is also the day when observant Jews remember the many tragedies which have befallen the Jewish people, including the Holocaust.
Some participants would have preferred a later eating window — more like noon to 8 p.m. — to fit in dinner with their family after work, but experts advised against it. It appears the more you can eat your food earlier in the day, the better, said Courtney Peterson, assistant professor of nutrition sciences at the University of Alabama at Birmingham. She’s the author of a small study published last year that found people who finished eating all their meals by early afternoon had smaller fluctuations in hunger and burned slightly more fat than people who ate throughout the day.
Save high-intensity interval training and heavy weight training for feed days/during your feed window, if you can, when you have the calories for fuel and nutrients for recovery. But if your training schedule calls for a grueling workout on a fast day that can’t be moved, add the calories burned to your count for the day so you don’t burn through muscle. At 200 or 300 calories, you don’t need to compensate, but if you burn 500 or more on a fast day, instead of just 500 maintenance calories with 50g of protein, eat 1,000 calories with 80g or more of protein, Varady advises.
Fasting should not be considered a "dieting method" either. We shouldn't fast to lose weight, but rather to gain deeper fellowship with God. Yes, anyone can fast. Some may not be able to fast from food (diabetics, for example), but everyone can temporarily give up something in order to focus on God. Even unplugging the television for a period of time can be an effective fast.
Fasting is a practice in several Christian denominations and is done both collectively during certain seasons of the liturgical calendar, or individually as a believer feels led by the Holy Spirit. In Western Christianity, the Lenten fast is observed by many communicants of the Catholic Church, Lutheran Churches, Methodist Churches, Reformed Churches, Anglican Communion, and the Western Orthodox Churches and is a forty-day partial fast to commemorate the fast observed by Christ during his temptation in the desert. While some Western Christians observe the Lenten fast in its entirety, Ash Wednesday and Good Friday are nowadays emphasized by Western Christian denominations as the normative days of fasting within the Lenten season.