If you’ve ever talked to me about nutrition, you would know that I’m a huge proponent of fasting. I knew that cultural and religious traditions throughout the world had incorporated some form of fasting practice into their doctrines, though I had not systematically tried to document it myself at the time. There may be a decent review article on this somewhere, but I decided to sit down and do a little research myself last year, and these are my notes from that exercise.
tl;dr: there are lots of different kinds of fasting. Some commonalities include the use of sunrise/sunset, fasting as a spiritual practice (opposed to mere starvation) including prayer and charity, proscribed feasting days/periods, and not drinking water either. Longer-term fasts usually restrict eating during daylight hours and/or restricted types of food during the night, and these appear to be the most common. Fasts of 1-2 days can involve complete cessation of both food and water. The strictest fast is 2 meals over 5 days. Fasting is at most 250 days/year, and 1-2 times per week or month is very common. Exceptions for the young, the old, the sick, pregnant and breastfeeding mothers, laborers, and travelers are relatively common. Not every religion has a fasting tradition.
Christianity – Catholicism
Fasting is not a complete cessation of food intake, instead it is a reduction of food intake to one large meal and two small meals (combined smaller than the large one) with no solid food between, and a prohibition against meat (specifically called abstinence). This is enforced during penitential times, specifically Lent (6 weeks), every Friday, occasional Wednesdays and Saturdays, the Ember Days (3 days/week 4 times/year), a couple specific holidays, and the day before some feast days.
This is the modern interpretation – the old church was far more strict. The “Black Fast” consisted of a single meal per day, to be eaten after sunset. Meat, eggs, dairy, and alcohol were forbidden. During the Holy Week (last week of Lent), the meal could only contain bread, salt, herbs, and water. Some Eastern Catholics still practice this on Fridays during Lent. This became weakened in the 14th century when the meal shifted to lunch, and then an evening snack was allowed. The 19th century saw the addition of the morning snack. In the 20th century you could substitute prayer and charity. The eastern Catholics are notably more strict, with one meal during the day, and avoiding animal products.
The prohibitions on fasting varied a lot by country, with entire countries receiving “dispensations” from the Pope. Abstinence is obligatory starting at age seven in many places, age fourteen by all of them. Obligatory fasting often starts at eighteen in western cultures. People who are sick and have physically demanding jobs, people over age 60 or so, also those who are traveling or students, are exempt.
Notably, one is expected to refrain from eating from midnight until the Eucharist, though when the Eucharist moved later in the day this changed to fasting >3 hours beforehand. So basically no food in your stomach during holy events. Technically modern Catholic law says only one hour.
Christian – Orthodoxy
Fasting is an important spiritual discipline, linked with the union between the body and the soul. Fasting is supposed to guard from glittery and impure thoughts/words/deeds, and must be accompanied by increased prayer and charity and repent sins and reaching out to others in love. It is spiritually harmful to fast without these practices.
Fasting occupies a large fraction of the calendar year. This includes Great Lent (40 days), Holy Week, Nativity Fast (40 days), Apostles’ Fast (variable but roughly one month), Dormition Fast (2 weeks), Wednesdays, Fridays, special holidays, and Mondays too for monks. Fasting consists of avoiding animal products, dairy, oil, alcohol, and sex (pre-communion only). When a feast day falls on a fasting period (or during the Nativity or Apostles’ fast), alcohol/oil and sometimes fish is allowed. The first five days of Lent (“Clean Week”) involves strict fasting, ideally only eating dinner on Wednesday and Friday after a liturgy. If you’re unable to comply, then you should eat only a little, and mostly raw vegetables, fruits, and nuts. Other days like Good Friday also encourage strict fasting through dinner on Holy Saturday, and occasionally people don’t drink water either. Similarly to Catholic tradition, no food from midnight until communion.
The very young, very old, sick, and breastfeeding are exempt.
The Coptic Orthodox are one of the most severe form of Christian fasting, for a total of 210 days out of the year. This is seen as a way to free ourselves from our carnal practices arising from the fall from grace, and to recognize and overcome our addictions and seek repentance. Fasting is viewed as a privilege rather than a hardship. The diet during a fasting period is strictly vegan, with added oils allowed. A “strict abstinence” is encouraged for people who can endure it, where no food or water is consumed until sunset. This has been progressively weakened from midnight to 3 PM, and then until noon, with the exception of Great Friday. Interestingly enough, sex is discouraged but not prohibited! Also notable is that 7 weeks out of the year, fasting is forbidden.
The Ethiopian Orthodox go even further, for a total of 250 fasting days. Fasting means no food or drink until after the liturgy (basically 2-3 PM), and a vegan diet in the evening. Children 13 and above have to fast, children 7 and above are expected to observe certain fasts. Sick people do not need to fast.
Christianity – Protestantism
Good old Martin blew this tradition out of the water as a “purely external observance” that could not gain a person salvation. He did actively encourage individuals to fast as a spiritual exercise, but believed each individual should set the time and manner of said fasting. John Calvin said that life should basically be perpetual fasting, and that collective public fasting was only appropriate for community grief. Basically fasting is not that common in protestants, even though it is verbally encouraged, particularly during Lent. Some individuals do voluntarily fast, and some of them on a strict schedule.
Christianity – Mormonism
Their tradition is “Fast Sunday” – abstaining from two meals the first Sunday of every month, for a 24 hour fasting window. This is accompanied by prayer and the money saved is donated to the church. During the service on that day, instead of a speaker people come up and offer their personal testimony.
Islam
Fasting is one of the Five Pillars of Islam (along with declaration of faith, prayer, charity, and pilgrimage).
Ramadan is one month long, no food during daylight hours (also no drinking or smoking or thinking evil thoughts or sex!). This could result in once-daily eating, but Muslims traditionally wake up 40-60 minutes before dawn to have a meal, so we’re basically talking two spaced meals. Probably still quite helpful – this is the most-studied form of IF and shows considerable benefits. There are also suggested non-obligatory fasting days, including all Mondays and Thursdays, or every other day. Certain holy days (esp feasting days) forbid fasting, and fasting every day is also not seen as proper.
People who shouldn’t fast: pre-pubescent children (though shorter fasts to warm them up is encouraged), sick people (including diabetes, and severe dehydration), the elderly, the mentally ill, pregnant and breastfeeding women, people who are traveling, menstruating women. A missed fast must be made up soon thereafter. Missing fasts should also be compensated by feeding the hungry.
The fast begins with setting an intention, this can be private. Breaking the fast intentionally results in another day of fasting, unless it is broken with sex… in which case you must either free a slave, fast for two months, or feed/clothe 60 people. The idea behind fasting is that it brings you closer to God, more solidarity with your fasting brothers, causes you to empathize with others less fortunate, and is a way of controlling desire. Fasting without spiritual intention is mere starvation.
Judaism
Traditional Judaism involves six fasting days during the year, and this means no eating or drinking from sunset to the following sunset (24 hours). On Yom Kippur and Tisha B’Av, one may also not wash oneself, wear leather uses, use perfume, or have sex – the other four days do not have these restrictions. There are less-observed fasts, including Bahab (three days on two months), the last day of every month, and firstborn sons have an additional day of fasting per year. Beyond that, the decision to fast is largely personal, and can come before a wedding, during tragedy/calamity, waking up from a bad dream, during droughts, after dropping a handwritten copy of the Torah… Mondays/Thursdays are considered good days for fasting. The purposes of fasting are threefold: atonement for sins, mourning, gratitude and focusing on the spiritual.
Buddhism
The “Middle Path” encourages neither excess nor mortification, and basically results in diminished food intake during meditation retreats for lay Buddhists.
Monks and nuns following Vinaya rules do not eat after their noon meal. This creates a very large fasting period! They actually do not consider this fasting, instead this is conceived of as a regimen for aiding meditation and good health.
The “eight precepts” contain prohibitions against various activities, including eating before sunrise or after noon (along with killing, stealing, sex, wrong speech, intoxication, singing/dancing/music/
The Vajrayana practice is more strict, to keep the eight precepts on the first day, followed by no food or water on the second. This conflicts with the Middle Path prohibition against mortification, though other self-harm is discouraged.
Hinduism
The Hindu term “vrata” means a religious practice with certain obligations, one of which can be complete or partial fasting. During a vrata period, one must remain clean, be celibate, speak truth, practice forbearance, be vegetarian, and perform rituals. Once undertaken a vrata should not be left unfinished, and another should not be started. You should not start a vrata during periods of ceremonial impurity brought by birth or death in the family. People too old or sick to undertake a vrata can have another do it for them. Once a decision is made to begin a vrata, the commencement of the vrata is bound by ceremonial times, places, and modes.
Monthly fasting periods include the sunset before to the sunrise after the Ekadashi (lunar phases that occur twice per month, ideally waterless fasting), the Pradosha (fast followed by a vigil), and the full moon. Different deities have different fasting days (Shiva=Monday, Vishnu=Thursday, etc), and different regions too (Tuesday in southern India, Thursday in northern India). Various festivals also involve fasting, such as Maha Shivaratri (no water), the nine days of Navratri (often one meal per day, or at least strictly vegetarian, plus other abstinence like no sex or beds or various things), Karva Chauth (fasting for a day by married women!)…
“Strict” fasting for Hindus means no food or water from sunset the day before, to 48 minutes after sunrise the following day, which is around 36 hours! More commonly is once-daily eating at dinner, and even more commonly is abstaining from particular foods. Even non-vegetarians are expected not to eat animal products (except milk).
Jainism
Extremely common among Jains. They have a ton of different kinds of fasts, including things like not eating to satiation. Complete fasting involves either no food and water, or only boiled water (to ensure no microorgasms are consumed). Jains are also strict vegetarians. Check out this list: http://en.wikipedia.org/wiki/
Fasting is used to keep the demands of the body under check, uplifting the soul, and resolving accumulated bad karma. During a fast one should worship, serve the monks and nuns, read scripture, meditate, and charity. Fasting is most common during festivals (three times/year for over a week) and on the 8th and 14th days of the moon cycle. The variation in fasts allows Jains to pick their level of fasting so as to maintain self-control. There is also a practice of voluntarily fasting to death, as a holy choice to leave the world – this reduction in food intake can happen gradually over years.
Bahai
There is one nineteen day fast that is one of the greatest obligations of the Bahai faith, considered a time to meditate and pray, make adjustments in inner life, and abstain from selfishness and carnal desire. This means no food or water during daylight hours, including smoking as well. You don’t have to fast if you’re under 15, above 70, the sick, women who are pregnant/nursing/menstruating, certain travelers, and heavy laborers (who must eat in private and take smaller meals).
Sikhism
They don’t believe fasting holds spiritual merit. The only reason to fast is for health purposes.
Raelism
I couldn’t forget my favorite cult, could I? Rael teaches that you should fast for 24 hours once per week to give rest to the digestive system.
