fasting#religious views

{{Short description|Willing abstinence from, or reduced consumption of, food and/or drink}}

{{Use dmy dates|date=January 2019}}File:Fasting 4-Fasting-a-glass-of-water-on-an-empty-plate.jpgFasting is the act of refraining from eating, and sometimes drinking. However, from a purely physiological context, "fasting" may refer to the metabolic status of a person who has not eaten overnight (before "breakfast"), or to the metabolic state achieved after complete digestion and absorption of a meal.{{Cite web|title=fasting {{!}} Definition, Description, Types, Benefits, & Facts|url=https://www.britannica.com/topic/fasting|access-date=2021-10-28|website=Encyclopedia Britannica|language=en}} Metabolic changes in the fasting state begin after absorption of a meal (typically 3–5 hours after eating).

A diagnostic fast refers to prolonged fasting from 1–100 hours (depending on age), conducted under observation, to facilitate the investigation of a health complication (usually hypoglycemia). Many people may also fast as part of a medical procedure or a check-up, such as preceding a colonoscopy or surgery, or before certain medical tests. Intermittent fasting is a technique sometimes used for weight loss or other health benefits that incorporates regular fasting into a person's dietary schedule. Fasting may also be part of a religious ritual, often associated with specific scheduled fast days, as determined by the religion, or be applied as a public demonstration for a given cause, in a practice known as a hunger strike.

Health effects

{{See also|Starvation response|Intermittent fasting|Autophagy|Fasting and longevity}}

Alternate-day fasting (alternating between a 24-hour "fast day" when the person eats less than 25% of usual energy needs, followed by a 24-hour non-fasting "feast day" period) has been shown to improve cardiovascular and metabolic biomarkers similarly to a calorie restriction diet in people who are overweight, obese or have metabolic syndrome.{{cite journal | vauthors = Cioffi I, Evangelista A, Ponzo V, Ciccone G, Soldati L, Santarpia L, Contaldo F, Pasanisi F, Ghigo E, Bo S | display-authors = 6 | title = Intermittent versus continuous energy restriction on weight loss and cardiometabolic outcomes: a systematic review and meta-analysis of randomized controlled trials | journal = Journal of Translational Medicine | volume = 16 | issue = 1 | pages = 371 | date = December 2018 | pmid = 30583725 | pmc = 6304782 | doi = 10.1186/s12967-018-1748-4 | type = Systematic review | doi-access = free }}{{cite journal | vauthors = Harris L, Hamilton S, Azevedo LB, Olajide J, De Brún C, Waller G, Whittaker V, Sharp T, Lean M, Hankey C, Ells L | display-authors = 6 | title = Intermittent fasting interventions for treatment of overweight and obesity in adults: a systematic review and meta-analysis | journal = JBI Database of Systematic Reviews and Implementation Reports | volume = 16 | issue = 2 | pages = 507–547 | date = February 2018 | pmid = 29419624 | doi = 10.11124/JBISRIR-2016-003248 | url = https://research.tees.ac.uk/ws/files/6438175/621636.pdf | access-date = 23 October 2019 | url-status = live | s2cid = 46780578 | archive-url = https://web.archive.org/web/20191030172956/https://research.tees.ac.uk/ws/files/6438175/621636.pdf | archive-date = 30 October 2019 }}{{cite journal | vauthors = Mattson MP, Longo VD, Harvie M | title = Impact of intermittent fasting on health and disease processes | journal = Ageing Research Reviews | volume = 39 | pages = 46–58 | date = October 2017 | pmid = 27810402 | pmc = 5411330 | doi = 10.1016/j.arr.2016.10.005 }}{{cite journal | vauthors = Papamichou D, Panagiotakos DB, Itsiopoulos C | title = Dietary patterns and management of type 2 diabetes: A systematic review of randomised clinical trials | journal = Nutrition, Metabolism, and Cardiovascular Diseases | volume = 29 | issue = 6 | pages = 531–543 | date = June 2019 | pmid = 30952576 | doi = 10.1016/j.numecd.2019.02.004 | s2cid = 86497236 | type = Systematic review }}

A 2021 review found that moderate alternate-day fasting for two to six months was associated with reductions of body weight, body mass index, and cardiometabolic risk factors in overweight or obese adults.{{Cite journal|last1=Patikorn|first1=Chanthawat|last2=Roubal|first2=Kiera|last3=Veettil|first3=Sajesh K.|last4=Chandran|first4=Viji|last5=Pham|first5=Tuan|last6=Lee|first6=Yeong Yeh|last7=Giovannucci|first7=Edward L.|last8=Varady|first8=Krista A.|last9=Chaiyakunapruk|first9=Nathorn|date=17 December 2021|title=Intermittent fasting and obesity-related health outcomes: An umbrella review of meta-analyses of randomized clinical trials|url=https://doi.org/10.1001/jamanetworkopen.2021.39558|journal=JAMA Network Open|volume=4|issue=12|pages=e2139558|doi=10.1001/jamanetworkopen.2021.39558|pmid=34919135|pmc=8683964|issn=2574-3805}}

= Medical application =

{{See also|Preoperative fasting|Body cleansing|Nothing by mouth}}

Fasting is almost always practiced prior to surgery or other procedures that require general anesthesia because of the risk of pulmonary aspiration of gastric contents after induction of anesthesia (i.e., vomiting and inhaling the vomit, causing life-threatening aspiration pneumonia).{{Cite web |url=https://abcnews.go.com/Health/WomensHealth/story?id=7161746&page=1 |title=Do You Need to Starve Before Surgery? |date=25 March 2009 |publisher=Abcnews.go.com |url-status=live |archive-url=https://web.archive.org/web/20110208095908/https://abcnews.go.com/Health/WomensHealth/story?id=7161746&page=1 |archive-date=8 February 2011 |access-date=18 October 2010}}{{Cite web |url=http://www.abc.net.au/health/minutes/stories/2004/06/17/1137544.htm |title=Fasting before surgery – Health & Wellbeing |last=Norman |first=Dr |date=17 April 2003 |publisher=Abc.net.au |url-status=live |archive-url=https://web.archive.org/web/20100529211055/http://www.abc.net.au/health/minutes/stories/2004/06/17/1137544.htm |archive-date=29 May 2010 |access-date=18 October 2010}}{{Cite web |url=http://www.yestheyrefake.net/anesthesia_full.htm |title=Anesthesia Information (full edition) | From Yes They're Fake! |date=1 January 1994 |publisher=Yestheyrefake.net |url-status=dead |archive-url=https://web.archive.org/web/20101112015650/http://www.yestheyrefake.net/anesthesia_full.htm |archive-date=12 November 2010 |access-date=18 October 2010}} Additionally, certain medical tests, such as cholesterol testing (lipid panel) or certain blood glucose measurements require fasting for several hours so that a baseline can be established.

= Mental health =

In one review, fasting improved alertness, mood, and subjective feelings of well-being, possibly improving overall symptoms of depression, and boosting cognitive performance.{{Cite journal |last1=Fond |first1=G |last2=MacGregor |first2=A |last3=Leboyer |first3=M |last4=Michalsen |first4=A |year=2013 |title=Fasting in mood disorders: Neurobiology and effectiveness. A review of the literature |url=http://www.hal.inserm.fr/inserm-00789122/document |url-status=live |journal=Psychiatry Research |volume=209 |issue=3 |pages=253–258 |doi=10.1016/j.psychres.2012.12.018 |pmid=23332541 |s2cid=39700065 |archive-url=https://web.archive.org/web/20180617165447/http://www.hal.inserm.fr/inserm-00789122/document |archive-date=17 June 2018 |access-date=4 November 2018}}

= Weight loss =

== Intermittent fasting ==

There is little evidence to suggest that intermittent fasting for periods shorter than 24 hours is effective for sustained weight loss in obese adults.{{Cite book |last1=Whitney |first1=Eleanor Noss |url=https://books.google.com/books?id=Mib1CAAAQBAJ&pg=SA7-PA21 |title=Understanding Nutrition |last2=Rolfes |first2=Sharon Rady |date=2012 |publisher=Cengage Learning |isbn=978-1133587521 |language=en |access-date=22 January 2017 |archive-url=https://web.archive.org/web/20170202031451/https://books.google.de/books?id=Mib1CAAAQBAJ&pg=SA7-PA21 |archive-date=2 February 2017 |url-status=live}}{{Cite journal |last1=Anton |first1=Stephen D |last2=Moehl |first2=Keelin |last3=Donahoo |first3=William T |last4=Marosi |first4=Krisztina |last5=Lee |first5=Stephanie A |last6=Mainous |first6=Arch G |last7=Leeuwenburgh |first7=Christiaan |last8=Mattson |first8=Mark P|display-authors=3 |year=2017 |title=Flipping the Metabolic Switch: Understanding and Applying the Health Benefits of Fasting |journal=Obesity |volume=26 |issue=2 |pages=254–268 |doi=10.1002/oby.22065 |pmc=5783752 |pmid=29086496}}

== Prolonged fasting ==

Prolonged fasting (also called extended fasting or water fasting) involves periods of fasting above 24 hours, typically in the range of 5–20 days.{{Cite journal |last1=Ezpeleta |first1=Mark |last2=Cienfuegos |first2=Sofia |last3=Lin |first3=Shuhao |last4=Pavlou |first4=Vasiliki |last5=Gabel |first5=Kelsey |last6=Varady |first6=Krista A. |date=2024-04-12 |title=Efficacy and safety of prolonged water fasting: a narrative review of human trials |journal=Nutrition Reviews |volume=82 |issue=5 |pages=664–675 |doi=10.1093/nutrit/nuad081 |issn=1753-4887 |pmid=37377031|pmc=11494232 }} In early fasting, the body operates under a relatively high level of gluconeogenesis, though this eventually decreases as the body's metabolism switches into ketosis, causing ketones to replace glucose as the primary energy source in the central nervous system.{{Cite journal |last1=Kerndt |first1=Peter R. |last2=Naughton |first2=James L. |last3=Driscoll |first3=Charles E. |last4=Loxterkamp |first4=David A. |date=November 1982 |title=Fasting: The History, Pathophysiology and Complications |journal=Western Journal of Medicine |volume=137 |issue=5 |pages=379–399 |issn=0093-0415 |pmc=1274154 |pmid=6758355}} As prolonged fasting continues, drastic decreases in sodium, potassium, magnesium, and other minerals are noted, which can lead to hyponatremia. In some diet systems, these losses are offset with non-caloric electrolyte supplements, such as electrolyte beverages.{{Cite web |title=Snake Diet—What It Is and Why It's Dangerous |url=https://www.health.com/weight-loss/what-is-snake-diet |access-date=2024-09-29 |website=Health |language=en}} Typical observed weight loss under prolonged fasting averages at 0.9 kg per day during the first week and 0.3 kg per day by the third week. In early fasting, during periods of high gluconeogenesis, roughly two-thirds of weight lost is lean muscle mass as opposed to fat.{{Cite journal |last=Cahill |first=G. F. |date=1983 |title=President's address. Starvation. |journal=Transactions of the American Clinical and Climatological Association |volume=94 |pages=1–21 |issn=0065-7778 |pmc=2279566 |pmid=6764569}} After the gluconeogenic phase, however, the ratio of body fat lost to lean tissue lost becomes roughly 7:6.

=Longevity=

There is no sound clinical evidence that fasting can promote longevity in humans.{{cite journal |vauthors=Lee MB, Hill CM, Bitto A, Kaeberlein M |title=Antiaging diets: Separating fact from fiction |journal=Science |volume=374 |issue=6570 |pages=eabe7365 |date=November 2021 |pmid=34793210 |pmc=8841109 |doi=10.1126/science.abe7365}}

Adverse effects

=Refeeding syndrome=

Refeeding syndrome is a metabolic disturbance which occurs as a result of reinstitution of nutrition in people and animals who are starved, severely malnourished, or metabolically stressed because of severe illness. When too much food or liquid nutrition supplement is eaten during the initial four to seven days following a malnutrition event, the production of glycogen, fat and protein in cells may cause low serum concentrations of potassium, magnesium and phosphate.{{cite journal |vauthors=Mehanna HM, Moledina J, Travis J |title=Refeeding syndrome: what it is, and how to prevent and treat it |journal=BMJ |volume=336 |issue=7659 |pages=1495–8 |date=June 2008 |pmid=18583681 |pmc=2440847 |doi=10.1136/bmj.a301 }}{{Cite journal|last1=Doig|first1=GS|last2=Simpson|first2=F|last3=Heighes|last4=Bellomo|first4=R|last5=Chesher|first5=D|last6=Caterson|first6=ID|last7=Reade|first7=MC|last8=Harrigan|first8=PWJ|date=2015-12-01|title=Restricted versus continued standard caloric intake during the management of refeeding syndrome in critically ill adults: a randomised, parallel-group, multicentre, single-blind controlled trial|journal=The Lancet Respiratory Medicine|volume=3|issue=12|pages=943–952|doi=10.1016/S2213-2600(15)00418-X|issn=2213-2619|pmid=26597128}} The electrolyte imbalance may cause neurologic, pulmonary, cardiac, neuromuscular, and hematologic symptoms—many of which, if severe enough, may result in death.

Refeeding syndrome can occur when someone does not eat for several days at a time usually beginning after 4–5 days with no food.{{cite journal |vauthors=Webb GJ, Smith K, Thursby-Pelham F, Smith T, Stroud MA, Da Silva AN |title=Complications of emergency refeeding in anorexia nervosa: case series and review |journal=Acute Medicine |volume=10 |issue=2 |pages=69–76 |year=2011 |doi=10.52964/AMJA.0470 |pmid=22041604 |doi-access=free }}

=Gallstones=

Fasting can increase the risk of developing gallstones for some people. This is thought to occur due to decreased gallbladder movement with no food to be digested, which can cause the bile to become over-concentrated with cholesterol, combined with the liver secreting extra cholesterol into bile as the body metabolizes fat during rapid weight loss, further exacerbating the situation.{{Cite web |title=Dietary advice for patients with gallstones |url=https://www.cuh.nhs.uk/patient-information/dietary-advice-for-patients-with-gallstones/ |access-date=2024-08-23 |website=Cambridge University Hospitals |language=en-GB}}

Political application

Fasting is often used to make a political statement, to protest, or to bring awareness to a cause. A hunger strike is a method of non-violent resistance in which participants fast as an act of political protest, or to provoke feelings of guilt, or to achieve a goal such as a policy change. A spiritual fast incorporates personal spiritual beliefs with the desire to express personal principles, sometimes in the context of social injustice.Garcia, M. (2007) The Gospel of Cesar Chavez: My Faith in Action Sheed & Ward Publishing p. 103

The political leader Gandhi undertook several long fasts as political and social protests. Gandhi's fasts had a significant impact on the British Raj and the Indian population generally.{{Cite journal|last=Harinarayanan|first=A.|date=1986|title=GANDHI'S FASTS : AN ANALYSIS (Summary)|url=https://www.jstor.org/stable/44141630|journal=Proceedings of the Indian History Congress|volume=47|pages=696–698|jstor=44141630|issn=2249-1937}}

In Northern Ireland in 1981, a prisoner, Bobby Sands, was part of the 1981 Irish hunger strike, protesting for better rights in prison.[http://news.bbc.co.uk/onthisday/hi/dates/stories/july/18/newsid_2514000/2514727.stm ON THIS DAY 1981: Violence erupts at Irish hunger strike protest] {{Webarchive|url=https://web.archive.org/web/20190417055938/http://news.bbc.co.uk/onthisday/hi/dates/stories/july/18/newsid_2514000/2514727.stm |date=17 April 2019 }}, BBC News Sands had just been elected to the British Parliament and died after 66 days of not eating. 100,000 people attended his funeral, and the strike ended only after nine other men died. In all, ten men survived without food for 46 to 73 days.

The American civil rights activist César Chávez undertook several spiritual fasts, including a 25-day fast in 1968 promoting the principle of nonviolence and a fast of 'thanksgiving and hope' to prepare for pre-arranged civil disobedience by farm workers.Shaw, R. (2008)Beyond the Fields: Cesar Chavez, the UFW, and the struggle for justice in the 21st century University of California Press, p.92 Chávez regarded a spiritual fast as "a personal spiritual transformation".Espinosa, G. Garcia, M Mexican American Religions:Spirituality activism and culture(2008) Duke University Press, p 108 Other progressive campaigns have adopted the tactic.Shaw, R. (2008)Beyond the Fields: Cesar Chavez, the UFW, and the struggle for justice in the 21st century University of California Press, p.93

Religious views

Fasting is practiced in various religions, and details of fasting practices differ.

Yom Kippur, Tisha B'av, Fast of Esther, Tzom Gedalia, the Seventeenth of Tamuz, the Tenth of Tevet, and Fast of the Firstborn are examples of fasting in Judaism.{{cite web |url=http://www.al-mawrid.org/pages/articles_english_detail.php?rid=196&cid=330&search=fasting |title=History of the Fast |access-date=2016-02-14 |url-status=dead |archive-url=https://web.archive.org/web/20141227090756/http://www.al-mawrid.org/pages/articles_english_detail.php?rid=196&cid=330&search=fasting |archive-date=27 December 2014}} Yom Kippur and Tisha B'Av are 25-hour fasts in which observers abstain from consuming any food or liquid from sunset until nightfall the next day and include other restrictions. The fasts of Esther, Gedalia, Tamuz, and Tevet all last from dawn until nightfall and therefore length varies depending on the time of the year. The Fast of the Firstborn is not biblically mandated and can therefore be ended early in the case of a seudat mitzvah.

Lent is a common period of fasting in Christianity. In the Catholic Church, the current practice of fast and abstinence is regulated by Canons 1250–1253 of the 1983 code.{{cite web |url=https://www.vatican.va/archive/ENG1104/__P4O.HTM |title=1983 Code of Canon Law |publisher=The Holy See |access-date=2011-11-19 |url-status=dead |archive-url=https://web.archive.org/web/20111115004422/https://www.vatican.va/archive/ENG1104/__P4O.HTM |archive-date=2011-11-15 }} They specify that all Fridays throughout the year, and the time of Lent are penitential times throughout the entire Church. All persons who have completed their fourteenth year are bound by the law of abstinence on all Fridays unless they are solemnities, and again on Ash Wednesday and Good Friday. Fasting must be observed by those who have attained their majority, until the beginning of their sixtieth year. The precept to both fast and abstinence must be observed on Ash Wednesday and Good Friday.

In addition to the fasts mentioned above, Catholics must also observe the Eucharistic Fast, which in the Latin Church involves taking nothing but water or medicine into the body for one hour before receiving the Eucharist{{1983CIC|919}}.

Eastern Orthodox Christians fast during specified fasting seasons of the year, which include not only the better-known Great Lent, but also fasts on every Wednesday and Friday (except on special holidays), together with extended fasting periods before Christmas (the Nativity Fast), after Easter (the Apostles' Fast) and in early August (the Dormition Fast).

Members of the Church of Jesus Christ of Latter-day Saints (Mormons) generally abstain from food and drink for two consecutive meals in a 24-hour period on the first Sunday of each month and use the money they save for charity.{{Cite web |title=The Law of the Fast |url=https://www.churchofjesuschrist.org/bc/content/ldsorg/topics/fasting-and-fast-offerings/PD60001350_TMP_2016%20LeadMtg_The%20Law%20of%20the%20Fast_9-15-16%20KW.pdf |access-date=7 October 2023 |website=The Church of Jesus Christ of Latter-day Saints}}

Muslims fast during the month of Ramadan each year. The fast includes refraining from consuming any food or liquid from dawn until sunset. It is a religious obligation for all Muslims unless they are children or are physically unable to fast.

Fasting is a feature of ascetic traditions in religions such as Hinduism and Buddhism.

Mahayana traditions that follow the Brahma's Net Sutra may recommend that the laity fast "during the six days of fasting each month and the three months of fasting each year".Brahma's Net Sutra, minor precept 30

Members of the Baháʼí Faith observe a Nineteen Day Fast from sunrise to sunset during March each year.

In alternative medicine

Although practitioners of alternative medicine promote "cleansing the body" through fasting,{{cite book|last1=Russell|first1=Sharman Apt|last2=Russell|first2=Sharman|title=Hunger: An Unnatural History|publisher=Basic Books|isbn=978-0786722396|url=https://books.google.com/books?id=XT2WzJuNPZ8C&pg=PT35|access-date=22 January 2017|language=en|date=1 August 2008|archive-url=https://web.archive.org/web/20170202031142/https://books.google.de/books?id=XT2WzJuNPZ8C&pg=PT35|archive-date=2 February 2017|url-status=live}} (as though it were a diagnostic fast) the concept of "detoxification“ is a marketing myth with little scientific basis for its rationale or efficacy.{{cite web |url=https://www.bda.uk.com/foodfacts/detoxdiets.pdf |publisher=British Dietetic Association |title=Detox diets |date=May 2016 |last=Porter |first=Sian |quote=The whole idea of detox is nonsense. The body is a well-developed system that has its own built-in mechanisms to detoxify and remove waste and toxins. Our body constantly filters out, breaks down and excretes toxins and waste products like alcohol, medications, products of digestion, dead cells, chemicals from pollution and bacteria |access-date=29 January 2019 |archive-url=https://web.archive.org/web/20161017170537/https://www.bda.uk.com/foodfacts/detoxdiets.pdf |archive-date=17 October 2016 |url-status=live }}{{cite web | title=Fashionably toxic | author=David Gorski | website=Science-Based Medicine | date=23 May 2011 | url=https://sciencebasedmedicine.org/fashionable-toxins/ | access-date=29 January 2019 | archive-url=https://web.archive.org/web/20190130001710/https://sciencebasedmedicine.org/fashionable-toxins/ | archive-date=30 January 2019 | url-status=live }}

During the early 20th century, fasting was promoted by alternative health writers such as Hereward Carrington, Edward H. Dewey, Bernarr Macfadden, Frank McCoy, Edward Earle Purinton, Upton Sinclair and Wallace Wattles.Griffith, R. Marie. (2000). Apostles of Abstinence: Fasting and Masculinity during the Progressive Era. American Quarterly 52 (4): 599-638. All of these writers were either involved in the natural hygiene or new thought movement. Arnold Ehret's pseudoscientific Mucusless Diet Healing System espoused fasting.Kuske, Terrence T. (1983). [https://www.sciencedirect.com/science/article/pii/B9780723670469500205 Quackery and Fad Diets] {{Webarchive|url=https://web.archive.org/web/20190420014820/https://www.sciencedirect.com/science/article/pii/B9780723670469500205 |date=20 April 2019 }}. In Elaine B. Feldman. Nutrition in the Middle and Later Years. John Wright & Sons. pp. 291-303. {{ISBN|0-7236-7046-3}}

Linda Hazzard, a notable quack doctor, put her patients on such strict fasts that some of them died of starvation. She was responsible for the death of more than 40 patients under her care.Hall, Harriett. (2016). [https://sciencebasedmedicine.org/natural-medicine-starvation-and-murder-the-story-of-linda-hazzard/ "Natural Medicine, Starvation, and Murder: The Story of Linda Hazzard"] {{Webarchive|url=https://web.archive.org/web/20190601162549/https://sciencebasedmedicine.org/natural-medicine-starvation-and-murder-the-story-of-linda-hazzard/ |date=1 June 2019 }}. Science-Based Medicine. Retrieved 1 May 2019.[https://www.medicalbag.com/home/features/despicable-doctors/linda-hazzard-the-starvation-doctor/ "Linda Hazzard: The “Starvation Doctor”"] {{Webarchive|url=https://web.archive.org/web/20190601162549/https://www.medicalbag.com/home/features/despicable-doctors/linda-hazzard-the-starvation-doctor/ |date=1 June 2019 }}. Retrieved 1 May 2019.

In 1911, Upton Sinclair authored The Fasting Cure, which made sensational claims of fasting curing practically all diseases, including cancer and syphilis.Upton Sinclair, The Fasting Cure (New York: Mitchell Kennerley, 1911), p. 44. Sinclair states he recommended fasting for all diseases except tuberculosis.Sinclair, The Fasting Cure, p. 44. Sinclair has been described as "the most credulous of faddists,"Walter Gratzer, Terrors of the Table: The Curious History of Nutrition (New York: Oxford University Press, 2005), p. 201. ISBN 0-19-280661-0. and his book is considered an example of quackery.Kang, Lydia; Pedersen, Nate. (2017). Quackery: A Brief History of the Worst Ways to Cure Everything. Workman Publishing. p. 265. {{ISBN|978-0-7611-8981-7}} In 1932, physician Morris Fishbein listed fasting as a fad diet and commented that "prolonged fasting is never necessary and invariably does harm".Fishbein, Morris. (1932). [https://archive.org/details/1932FishbeinFadsAndQuackeryInHealing/page/n261 Fads and Quackery in Healing: An Analysis of the Foibles of the Healing Cults]. New York: Covici Friede. p. 253

Types of fasting

= Type by religion =

= Type by method =

Electrolyte supplemented water fasting
Dry fasting
Juice fasting
Water fasting
Snake diet

= Type by schedule =

Source:{{Cite web |title=Intermittent Fasting: How It Works |url=https://health.clevelandclinic.org/intermittent-fasting-4-different-types-explained |access-date=2024-08-23 |website=Cleveland Clinic |language=en}}

Alternate day
Eat: stop: eat
Intermittent fasting
One Meal A Day (OMAD)/Warrior diet
Prolonged fasting
The 16/8 or 14/10
The 40-days and 40-nights
The 5:2

= Type by motivation =

Autophagy
Avoidant/restrictive food intake disorder
Calorie restriction
Drunkorexia
Hunger strike
Inedia
Insulin resistance management
Longevity
Sallekhana
Weight loss

References

External links

{{Cite EB1911 |wstitle=Fasting |volume=10 |pages=193–198 |short=x}}
{{Cite NIE |wstitle=Fast |year=1905 |short=x}}
{{Cite CE1913 |last=O'Neill |first=James David |wstitle=Fast |volume=5 |short=x}}