A healthy diet is always the key to a healthy lifestyle. It’s especially important to eat healthy if you are fasting; even though you’re eating less, you still need to take in the essential vitamins, minerals, and nutrients your body needs to function . Try to get the recommended servings of fruits and vegetables, as well as protein and grains, into your daily diet.
Alternative medicine A period of voluntary abstinence from foods and/or drinks; fasting is integral to many religions, as it is believed to purify the mind and spirit; fasting rests the GI tract, and may rid the body of toxins and undigested metabolites; fasting leads to a loss of water, Na+, and K+, resulting in postural hypotension, and decreased blood sugar resulting in depression, fatigue, decreased libido, and malaise, increased nitrogen in the circulation due to protein breakdown, and may result in premature childbirth—Yom Kippur effect
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.
Intermittent fasting (specifically the 5:2 diet) became popular in the UK in 2012 after the BBC2 television Horizon documentary Eat, Fast and Live Longer. Via sales of best-selling books, it became widely practiced. In the United States, intermittent fasting has become a trend among Silicon Valley companies. According to NHS Choices as of 2012, people considering the 5:2 diet should first consult a physician, as fasting can sometimes be unsafe. A news item in the Canadian Medical Association Journal expressed concern that promotional material for the diet showed people eating high-calorie food, such as hamburgers and chips, and that this could encourage binge eating since the implication was that "if you fast two days a week, you can devour as much junk as your gullet can swallow during the remaining five days".
TV/Movie Fast: You can take a break from a weekly favorite and use the time to pray or read the Bible. Is there a small group at church that you've thought about joining but it's during the time your show is on? Do you spend your Saturday binging Netflix when you could take some time to mentor someone God has placed on your heart? This is also a good time to evaluate how much of your time is spent watching TV and whether you need to cut back to make time for other priorities.
In section 109, of the same book, Yudhishthira asks Bheesma "what is the highest, most beneficial" and fruitful "of all kinds of fasts in the world". Bheeshma says "fasting on the 12th day of the lunar month" and worship Krishna, for the whole year. Krishna is worshipped in twelve forms as Kesava, Narayana, Madhava, Govinda, Vishnu, the slayer of Madhu, who covered the universe in three steps, the dwarf (who beguiled Mahabali), Sridhara, Hrishikesha, Padmanabha, Damodara, Pundhariksha. and Upendra. After fasting, one must feed a number of brahmans. Bheeshma says " the illustrious Vishnu, that ancient being, has himself said that there is no fast that possesses merit superior to what attach to fast of this kind." 
If your doctor has told you that you're in danger of developing diabetes, ask him or her if IF is worth a try. This type of eating plan may help your cells become more sensitive to insulin, says Foroutan. The reason: Every time you eat, your body releases the hormone insulin in an attempt to shuttle sugar from your bloodstream into your cells for energy. But people who are prediabetic are insulin resistant, which means the cells in your body don't respond well to insulin and can't take up glucose so your blood sugar levels stay elevated. Going longer between eating may help because it requires your body to pump out insulin less often.
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:
DU: The biggest benefit of fasting is disciplining us to focus on God long enough to be changed by Him. I have seen brothers and sisters who, after spending much time in God’s presence through prayer and fasting, have been significantly empowered to carry out God’s call on their lives. From a medical perspective, there are a significant number of credible studies showing that fasting substantially reduces the risk for type 2 diabetes, heart disease, and cancer. I reviewed scientific literature on the health benefits of fasting going back up to 70 years, and what I found is that fasting improves our health span if it is done consistently and intermittently as a lifestyle.
Hunger suppression. A ketogenic diet suppresses hunger, too. On a keto diet, your liver turns fat into little bundles of energy called ketones, which it then sends through your bloodstream for your cells to use as fuel. Ketones suppress ghrelin, your body’s main hunger hormone. High ghrelin makes you hungry. On keto, your ghrelin stays low, even when you don’t have food in your system. In other words, you can go longer without eating and you won’t get hungry. Fasting becomes significantly easier on keto so you can fast for longer windows to reap all the benefits.
In 2017, Longo was a co-author on the first human trial of whether fasting might reduce the risk factors for diseases like diabetes, cancer, and cardiovascular disease. The researchers randomized 100 people into one of two groups for three months: The first group ate anything they wanted, and the second fasted for five consecutive days each month. (By “fasted” here, I mean, they followed the fasting-mimicking diet.) After three months, the first group was crossed over into the fasting group, so the researchers could gather even more data on fasting.
^ Guéranger, Prosper; Fromage, Lucien (1912). The Liturgical Year: Lent. Burns, Oates & Washbourne. p. 8. St. Benedict's rule prescribed a great many fasts, over and above the ecclesiastical fast of Lent; but it made this great distinction between the two: that whilst Lent obliged the monks, as well as the rest of the faithful, to abstain from food till sunset, these monastic fasts allowed the repast to be taken at the hour of None.
The findings were clear: Fasting just five days per month improved people’s health outcomes. The group that fasted lost weight (about 7 pounds on average), lost some body fat, lowered their blood pressure, and decreased their IGF-1, a genetic marker for diseases such as cancer. (Their total cholesterol, blood glucose, and triglycerides didn’t budge.)
That’s the principle behind the diet method known as intermittent fasting. Unlike many popular diets, intermittent fasting has the backing of scientific research (including a massive 2017 study analysis by the International Society of Sports Nutrition), which suggests that intermittent fasting is just as effective as daily calorie restriction—sometimes better—at improving body composition. Furthermore, intermittent fasting doesn’t involve any calorie counting, and may suppress hunger better than traditional low-calorie diets.
Jesus’ statements concerning fasting are simple and straightforward. His disciples will fast (Luke 5:33-35 Luke 5:33-35 33 And they said to him, Why do the disciples of John fast often, and make prayers, and likewise the disciples of the Pharisees; but your eat and drink? 34 And he said to them, Can you make the children of the bridal chamber fast, while the bridegroom is with them? 35 But the days will come, when the bridegroom shall be taken away from them, and then shall they fast in those days.
If you really want to lose fat, intermittent fasting is the perfect tool. Research shows that intermittent fasting — cycling in and out periods of fasting and eating — has huge benefits for your body and brain. It can ward off chronic disease, improve memory and brain function, and boost your energy levels. What’s more, intermittent fasting is a powerful hack for losing weight quickly, and keeping it off.
I sometimes hear people say, "I'm giving up chocolate" and they regard this as a type of fasting. I think this is a rather frivolous approach. The first and foremost purpose of a biblical or spiritual fast is to get a breakthrough on a particular matter that one lifts up to the Lord in prayer. A spiritual fast involves our hearts and the way in which we relate to and trust God. It relates to discerning and receiving strength to follow through on what God might reveal to us about circumstances in our lives or a direction we are to take.
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.
Although I do not fast like you do (from sunrise to sunset) I do continue to fast not just to maintain my weight but to free the mind and body or the extra weight and burdens that it must carry. You see when your stomach is not full and your mind is not sluggish from trying to digest a heavy meal you start to have more energy think clearer, sleep better and feel better. When you can have this in your life for free why not take it. Some people spend thousands to have access to these feelings when we can experience a little bit of this each week.
Fasting can take up a significant portion of the calendar year. The purpose of fasting is not to suffer, but according to Sacred Tradition to guard against gluttony and impure thoughts, deeds and words. Fasting must always be accompanied by increased prayer and almsgiving (donating to a local charity, or directly to the poor, depending on circumstances). To engage in fasting without them is considered useless or even spiritually harmful. To repent of one's sins and to reach out in love to others is part and parcel of true fasting.