This is a type of spiritual fasting. Based off of Daniel’s experiences in the Bible’s Book of Daniel, the Daniel Fast is a partial fast where vegetables, fruits and other healthy whole foods are featured prominently, but meat, dairy, grains (unless they’re sprouted ancient grains) and drinks like coffee, alcohol and juice are avoided. Most people follow this fast for 21 days in order to experience a spiritual breakthrough, have more time to reflect on their relationship with God or just to feel closer to what Daniel would have experienced in his time.

A systematic review of 40 studies found that intermittent fasting was effective for weight loss, with a typical loss of 7-11 pounds over 10 weeks. [2] There was much variability in the studies, ranging in size from 4 to 334 subjects, and followed from 2 to 104 weeks. It is important to note that different study designs and methods of intermittent fasting were used, and participant characteristics differed (lean vs. obese).  Half of the studies were controlled trials comparing the fasting group to a comparison group and/or a control group (either continuous calorie restriction or usual lifestyle), with the other half examining an intermittent fasting group alone. A brief summary of their findings:

Thirty-six young healthy male volunteers were placed on a 24-week calorie-restricted diet of about 1,600 calories per day. They also had to walk for about 45 minutes a day. But instead of resulting in continuous weight loss, at 24 weeks their weight had stabilized, and no more weight loss could be elicited even when he reduced calorie intake down to 1,000 or less per day.
I take a 1200 calorie diet and I exercise. A lot. In the morning I have a cup of coffee and do a 1:30hr workout consisting of 2 HIIT workouts and a strength workout along with A 20 minute fat burning yoga. I open my fast at 2pm and stop eating at 8pm after 3 hours before sleeping I do another 1 hr workout. One HIIT workout and some cardio. Then I go to sleep. Acc to my calorie calculator I burn around 600-800 calories. I try my best to eat as healthy as possible but I’m seeing no results. I tried following all the advices I could find but I don’t understand what’s wrong. People are losing this much weight in a week. It’s very disheartening for me.
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)
Where diets complicate life, fasting simplifies. Where diets are expensive, intermittent fasting is free. Where diets can take time, fasting saves time. Where diets are limited, fasting is available anywhere. Where diets have variable efficacy, fasting has unquestioned efficacy. There is no more powerful method for lowering insulin and decreasing body weight.

Longo warned that any fasting diet should start with a visit to the doctor. Fasting studies have not been done in children, very elderly people, or people who are underweight — so it’s possible fasting could be harmful in these cases. “If you’re a diabetic and taking insulin or any other drugs, or if you have metabolic disorders, you should not fast,” he added, noting that fasts done poorly can also increase the risk of gallstones.

Fasting during religious festivals is also very common. Common examples are Maha Shivaratri (Most people conduct a strict fast on Maha Shivratri, not even consuming a drop of water ), or the nine days of Navratri (which occurs twice a year in the months of April and October/November during Vijayadashami just before Diwali, as per the Hindu calendar). Karwa Chauth is a form of fasting practised in some parts of India where married women undertake a fast for the well-being, prosperity, and longevity of their husbands. The fast is broken after the wife views the moon through a sieve. In the fifth month (Shravan Maas) of the Hindu calendar, many celebrate Shraavana. During this time some will fast on the day of the week that is reserved for worship of their chosen god(s), while others will fast during the entire month.[82]
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).

Meaning and definition of fasting, what is fasting in the bible, fasting definition, why should I fast, the power of prayer and fasting, Location of Galilee, where was galilee in the bible?, fasting definition, Galilee region, cities of Galilee, Sea of Galilee, Definition of biblical fire, what is fire in the bible?, fire and brimstone, fire meaning, baking bread with fire, Definition of the biblical firmament in Genesis, what is the firmament in the bible?, was the firmament the third heaven, firmament meaning, did the firmament bring the flood of Noah?.

Thank you very much for the great article. As a Muslim, we are encouraged to fast two days a week (Monday and Thursday)! It is not a must, just preferred. We fast from sunrise to sunset. No food or drink is allowed during this period (no water). As you mentioned a true fast can be a mental and physical cleansing time. From a personal experience, fasting is really great. I strongly believe it has many benefits on the mind and body as well if done correctly.
Still, it's important to note that the results of intermittent fasting are no better than a calorie-restricting diet. A 2017 study in JAMA showed that alternate-day fasting doesn't produce superior benefits for weight loss than daily calorie restriction, and similar conclusions were drawn in a 2018 study published in the American Journal of Clinical Nutrition. So if you don't think fasting is right for you, restricting calories works just as well.
You’re consuming less food and thus spending less money. Rather than overeating to put on 1 pound of muscle and 4 pounds of fat in a week or two, you’re aiming to eat exactly enough to put on 1 pound of muscle without adding much fat on top of it.  Yeah, it’s a delicate balance, but there’s far less swing involved. You are just slowly, steadily, and consistently building muscle and strength over many months.

As long as you’re aware that it isn’t nutritional magic, Sasson isn’t against intermittent fasting altogether. “I’ve worked with patients who need positive reinforcement to see that their weight went down to feel better, and they feel in control for the first time,” she says. “That self-efficacy, that feeling that they could do it—for some, that might be important.”
By the ninth century b.c. fasting had become institutionalized or formalized to the extent that days or other periods of fasting were called as occasions for public worship. The usual way of describing such convocation is "to call for" or "proclaim" a fast. Thus, Jezebel, to provide an occasion whereby Naboth would be unjustly accused and condemned, proclaimed a fast ( 1 Kings 21:9 1 Kings 21:12 ). Jehoshaphat later, and with much nobler motives, called for such an assembly in order to implore God's intercession on Judah's behalf ( 2 Chron 20:3 ). The same formula appears in ezr 8:21 and jon 3:5, in the last instance initiated by the people of Nineveh as an expression of their repentance at Jonah's preaching.
In Yoga principle, it is recommended that one maintains a spiritual fast on a particular day each week (Monday or Thursday). A fast should also be maintained on the full moon day of each month. It is essential on the spiritual fasting day to not only to abstain from meals, but also to spend the whole day with a positive, spiritual attitude. On the fasting day, intake of solid food during the day is avoided and only a light veggie meal around 5 o'clock is taken. Water can be taken any time as needed. If health does not permit fasting for a whole day, for example with Diabetes, careful planning is done to reduce or skip one meal.[92]

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.