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.
Fasting from food is not necessarily for everyone. Some health conditions keep even the most devout from the traditional course. However, fasting is not limited to abstaining from food. As Martyn Lloyd-Jones said, “Fasting should really be made to include abstinence from anything which is legitimate in and of itself for the sake of some special spiritual purpose.”
Many physiological changes occur in the body during fasting. During the first day or so, the body uses its glycogen reserves, the sugars that are the basic energy supply. After these are depleted, the body begins using fat. However, the brain, which has high fuel requirements, still needs glucose (sugars converted from glycogen). To obtain glucose for the brain, the body begins to break down muscle tissue during the second day of the fast. Thus, during fasting some muscle loss will occur. To fuel the brain, the body would need to burn over a pound of muscle a day, but the body has developed another way to create energy that saves important muscle mass. This protein-sparing process is called ketosis, which occurs during the third day of a fast for men and the second day for women. In this highly efficient state, the liver begins converting stored fat and other nonessential tissues into ketones, which can be used by the brain, muscles, and heart as energy. It is at this point in the fast that sensations of hunger generally go away, and many people experience normal or even increased energy levels. Hormone levels and certain functions become more stable in this state as well. The goal of most fasts is to allow the body to reach the ketosis state in order to burn excess fat and unneeded or damaged tissue. Thus, fasts longer than three days are generally recommended as therapy.
Good Friday, which is towards the end of the Lenten season, is traditionally an important day of communal fasting for Methodists. Rev. Jacqui King, the minister of Nu Faith Community United Methodist Church in Houston explained the philosophy of fasting during Lent as "I'm not skipping a meal because in place of that meal I'm actually dining with God".
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." 
1) A soul cleansing. How often we forget that our bodies are the temple of the Lord—especially when deciding what to eat! Fasting is a great time to remember the spiritual connection we have to our physical bodies. Without the toxins we put in our bodies, we not only give our bodies a break from the digestive process, but we also allow our spirits to be detoxed. Fasting is a faith-move, an expectation we have that God will fill us with His Holy Spirit, just as He promised. But as Christ told His disciples, “[N]o one pours new wine into old wineskins. Otherwise, the wine will burst the skins, and both the wine and the wineskins will be ruined. No, they pour new wine into new wineskins." By fasting, we meditate cleanses the soul and makes it new so we can receive the Holy Spirit and become empowered to live for Christ in a new way.
So what’s the first step in getting started? Each method has its own guidelines for how long to fast and what to eat during the “feeding” phase. Below, you’ll find the five most popular methods and the basics of how they work. Keep in mind, intermittent fasting isn’t for everyone. Those with health conditions of any kind should check with their doctor before changing up their usual routine. Note that personal goals and lifestyle are key factors to consider when choosing a fasting method.
^ Harris, Elizabeth J. (7 June 2010). "Violence and Disruption in Society: A Study of the Early Buddhist Texts". Access to Insight. John T. Bullitt. Retrieved 7 June 2011. If you, Rahula, are desirous of doing a deed with the body, you should reflect on the deed with the body, thus: "That deed which I am desirous of doing with the body is a deed of the body that might conduce to the harm of self and that might conduce to the harm of others and that might conduce to the harm of both; this deed of body is unskilled (akusala), its yield is anguish, its result is anguish.
The Fast Diet is only an eating pattern, but that doesn't mean you shouldn't exercise. In fact, being physically active lowers your risk of heart disease and diabetes, helps keep weight off and increases your energy level. Most experts suggest getting at least 30 minutes of moderate-intensity exercise – like brisk walking – most or all days of the week.
Keep in mind that the initial weight lost on a fast is primarily fluid or "water weight," not fat. And when you go back to eating, any lost weight usually gets a return ticket back. Not only do most people regain weight lost on a fast, they tend to add a few extra pounds because a slower metabolism makes it easier to gain weight. Worse, the weight that is regained is likely to be all fat -- lost muscle has to be added back at the gym.
Another aspect of fasting for God is comparable to a person dedicating an action to a cause. For God and country was, at one time, a familiar declaration in the United States. It implied that the action being taken was to answer a noble call and serve a higher motive, the expectation of reward or compensation being far removed. The motivation came from a spiritual, emotional and dedicated commitment to do what is right. Similarly, a fast may be undertaken for God because it represents a lofty act, a selfless commitment to an act considered meritorious and virtuous.
The participants ended up eating 350 fewer calories a day compared to a control group just because they couldn’t squeeze in their normal food intake between 10 a.m. to 6 p.m., the prescribed eating window in the study, said Krista Varady, co-author and an associate professor of nutrition at the University of Illinois, Chicago, who has been studying fasting for 12 years.
In a sense, everyone fasts. When we are in bed asleep, we go without any food or drink. That is fasting. That is why the first meal of the day is called breakfast. However, when people speak of fasting, they usually mean a longer period of time of deliberately choosing not to eat and drink. It can be for a whole day, part of a day or more than a day.
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.