Intermittent fasting

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
Intermittent fasting is a strategy for meal timing scheduling.

Intermittent fasting, also known as intermittent energy restriction, is an umbrella term for various meal timing schedules that cycle between voluntary fasting (or reduced calories intake) and non-fasting over a given period.[1][2] Non-caloric, and sometimes low-caloric, drinks can be used during intermittent fasting, contrary to strict fasting which disallows fluid intake in some religious practices.[3][4]

Three methods of intermittent fasting are alternate-day fasting, periodic fasting, and time-restricted feeding.[5] Intermittent fasting may be similar to a calorie restriction diet.[1] Although being studied in the 21st century as a practice to possibly reduce the risk of diet-related diseases,[1][6][7][8] intermittent fasting is also regarded as a fad.[9]

The science concerning intermittent fasting is preliminary and inconclusive.[10] The American Heart Association (AHA) states that intermittent fasting may produce weight loss, reduce insulin resistance, and lower the risk of cardiometabolic diseases, although its long-term sustainability is unknown.[1] The US National Institute on Aging (NIA) recommends against intermittent fasting because of uncertainties about its effectiveness and safety, particularly for the elderly.[10]

Diverse forms of intermittent fasting exist in various religious practices, including Vrata in Hinduism, Ramadan fasting (Islam), Yom Kippur fasting and other Jewish fasts (Judaism), Orthodox Christian fasting, Fast Sunday (The Church of Jesus Christ of Latter-day Saints), and Buddhist fasting.[2][11]

Types[edit]

An alternate day fasting schedule, that alternates between usual eating (feast days) and fast days with reduced or no calories

Three methods of intermittent fasting are alternate-day fasting, periodic fasting, and time-restricted feeding:[2][5][9][12][13]

  • Alternate-day fasting involves alternating between a 24-hours "fast day" when the person eats less than 25% of usual energy needs, followed by a 24-hour non-fasting "feast day" period. It is the strictest form of intermittent fasting because there are more days of fasting per week.[1][5] There are two subtypes:[3][9]
    • Complete alternate-day fasting (or total intermittent energy restriction), where no calories are consumed on fast days.
    • modified alternate-day fasting (or partial intermittent energy restriction) which allows the consumption of up to 25% of daily calorie needs on fasting days instead of complete fasting. This is akin to alternating days with normal eating and days with a very-low-calorie diet.[14]
  • Periodic fasting or whole-day fasting involves any period of consecutive fasting of more than 24h, such as the 5:2 diet where there are 1 or 2 fast days per week, to the more extreme version with several days or weeks of fasting. During the fasting days, it may be allowed approximately 500 to 600 calories or about 25% of regular daily caloric intake instead of complete fasting.[1][3][5][15]
  • Time-restricted feeding involves eating only during a certain number of hours each day. Skipping a meal and the 16:8 diet (16 fasting hours cycled by 8 non-fasting hours) are examples. This schedule is thought to leverage the circadian rhythm.[1][5][16]

Applications[edit]

The science concerning intermittent fasting is preliminary and uncertain due to an absence of studies on its long term effects.[1][17][10][18] There is preliminary evidence that intermittent fasting may be effective for weight loss, may decrease insulin resistance and fasting insulin, and may improve cardiovascular and metabolic health, although the long term sustainability of these effects has not been studied.[1]

The AHA recommends intermittent fasting as an option for weight loss and calorie control as part of an "intentional approach to eating that focuses on the timing and frequency of meals and snacks as the basis of a healthier lifestyle and improved risk factor management".[1] For overweight people, fasting may be integrated into a wider dietary change, such as "placing snacks strategically before meals that might be associated with overeating", planning meals and snacks throughout the day to help manage hunger and control meal portions, and "promote consistent overnight fast periods".[1] The AHA noted that eating some food on a fast day (instead of a complete fast) produced the greatest weight loss and decreases in insulin resistance, when at least 4% weight loss was achieved by obese individuals.[1]

The American Diabetes Association "found limited evidence about the safety and/or effects of intermittent fasting on type 1 diabetes" and preliminary results of weight loss for type 2 diabetes, and so does not recommend any specific dietary pattern for the management of diabetes until more research is done, recommending instead that "health care providers should focus on the key factors that are common among the patterns".[17]

New Zealand's Ministry of Health considers that intermittent fasting can be advised by doctors to some people, except diabetics, stating that these "diets can be as effective as other energy-restricted diets, and some people may find them easier to stick to" but there are possible side effects during fasting days such as "hunger, low energy levels, light-headedness and poor mental functioning" and note that healthy food must be chosen on non-fast days.[18][19]

Although intermittent fasting showed weight loss success in several studies on obese or overweight individuals, the NIA does not recommend intermittent fasting for non-overweight individuals because of uncertainties about its effectiveness and safety, especially for older adults.[10]

Usage trends[edit]

As of 2019, intermittent fasting is a common fad diet, attracting celebrity endorsements and public interest.[20]

UK[edit]

Intermittent fasting (specifically the 5:2 diet of Michelle Harvie and Mark Mattson and popularized by Michael Mosley) became popular in the UK in 2012[21][22] after the BBC2 television Horizon documentary Eat, Fast and Live Longer.[23] Via sales of best-selling books, it became widely practiced.[24][25]

North America[edit]

In the United States, intermittent fasting became a fad among Silicon Valley companies.[26] It was the most popular diet in 2018 according to a survey by the International Food Information Council.[27][28] According to NHS Choices, people considering the 5:2 diet should first consult a physician, as fasting can sometimes be unsafe.[24][29] 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".[30] However, the idea of binge eating following dietary restrictions stems from an extrapolation of a post-war famine study, where nineteen prisoners of war were observed during their re-habilitation with unlimited access to food, and found they tended to indulge in binge eating.[14]

Commercialization[edit]

As of 2019, interest in intermittent fasting led some companies to commercialize diet coaching, dietary supplements, and full meal packages.[26][31] These companies have been criticized for offering products or services that are expensive and not backed by science.[31][32]

Research[edit]

Weight loss[edit]

There is some limited evidence that intermittent fasting produces weight loss comparable to a calorie restricted diet.[6][7][8][33][34][35] Most studies on intermittent fasting in humans observed weight losses, ranging from 2.5% to 9.9%.[36][37] Alternate day fasting does not affect lean body mass,[5][38] although one review found a small decrease.[39] Alternate day fasting improves cardiovascular and metabolic biomarkers similarly to a calorie restriction diet for people who are overweight, obese or have a metabolic syndrome.[6][8][13][15][40]

Intermittent fasting has not yet been studied in children, the elderly, or underweight people, and could be harmful in these populations.[6][8][10][41] Intermittent fasting is not recommended for people who are not overweight.[10] The long-term sustainability of intermittent fasting is unknown, as of 2018.[10][42][43]

Other effects[edit]

Night-time eating has been linked to impaired sleep quality.[3] There is no evidence that fasting has any beneficial effect (prevention, treatment, drugs interaction) for cancer and is thus not recommended in France,[15][44][45] the United Kingdom,[46] or the United States,[47] although a few small-scale clinical studies suggest that intermittent fasting may reduce chemotherapy side effects.[48][49] Periodic fasting may have minor effect on chronic pain and mood disorders.[50][51][52] Intermittent fasting does not affect bone health.[53]

Athletic performance does not benefit from intermittent fasting.[54] Overnight fasting before exercise increases lipolysis, but reduces performance in prolonged exercise (more than 60 min).[55][56]

Adverse effects[edit]

Reviews of preliminary clinical studies found that short-term intermittent fasting may produce minor adverse effects, such as continuous feelings of weakness and hunger, headaches, fainting, or dehydration. However, the data remain sparse, as most studies did not analyze adverse effects specifically.[6][34][57][58] A 2018 systematic review found no major adverse effect.[6] Periodic fasting prolonged for several days or weeks may cause eating disorders, malnutrition, increased susceptibility to infectious diseases, moderate damage to organs[57] or sudden death by cardiac failure, either during fasting or upon refeeding.[57][14] Deaths also happened following therapeutic prolonged periodic fasting.[13] These effects happened after several weeks of fasting,[13] intermittent fasting should not produce these adverse effects,[57] and has not been reported to do so in clinical trials as of 2018,[13][59] but it may still cause harm when practiced too frequently or for too many consecutive days.[57] Intermittent fasting is not recommended for pregnant or breastfeeding women, or children and adolescents during maturation, or individuals vulnerable to eating disorders.[12]

Tolerance[edit]

Tolerance of a diet is a determinant of its potential effectiveness and maintenance of benefits obtained, such as weight loss or biomarker improvement.[34] A 2019 review found that drop-out rates varied widely from 2% to 38% for intermittent fasting, and from 0% to 50% for a calorie restriction diet.[6]

Mechanism[edit]

Fasting makes the body transition through four states: from the fed state or absorptive state or postprandial state, when the gastrointestinal tract is full and the primary fuel source is glucose and body fat storage is activated and lasting about 4h,[60][61] to the early fasted state or postabsorptive state, happening a few hours after eating and lasting up to 12-18h, when glucagon is secreted stopping fat storage and the body instead uses liver glucose reserves as a fuel source[5][60] to the fasted state transitioning progressively[62] to other reserves such as fat, lactate and alanine as a fuel source,[60][61] and when the liver glucose reserves are depleted after usually 12 to 36h of continued fast, the body enters the starvation state where only the other reserves are used as fuel,[13][61][63][64] which represents a shift from preferential lipid synthesis and fat storage to the mobilization of fat in the form of free fatty acids then derived into fatty acid-derived ketones to provide energy to organs.[13][61][65][66] This transition to free fatty acids as the fuel source manifests as a reduction in the respiratory exchange ratio (ratio of CO2 exhaled to O2 inhaled).[67][68] Sirt 1, the mammal variant from the sirtuin family of signaling proteins with a highly conserved structure throughout all kingdoms of life,[69] is involved in the regulation of this transition and mediation of gluconeogenesis.[13][70] Some authors call this transition a "metabolic switch".[13][71] Whether repeatedly triggering this transition between fed, fasted and starvation states, as does intermittent fasting, may produce meaningful health benefits regardless of weight loss and caloric restriction has not yet been determined.[35][61] A review of a wide variety of diets, including alternate day fasting, show they all produce similar weight loss and cardiometabolic changes, with adherence and negative energy balance being better predictors than the type of diet.[35][59] IGF-1 level decreases have been observed in a systematic review during either intermittent fasting or more than 50% continuous calorie restriction.[72] Another systematic review did not find evidence of a reduction of adaptive responses, except maybe appetite, when using intermittent fasting, although most studies were under-powered to assess this.[73]

These mechanisms are known from studies on starvation that have been conducted for over 100 years in the 20th century, which allowed to derive a substantial amount of research examining varying durations of food deprivation on humans.[5][14] However, the majority of short-term starvation studies extend through at least the fasted state, with periods of approximately 2 to 4 days of fast, which is longer than most intermittent fasting patterns.[5]

Intermittent fasting may affect several metabolic pathways in humans, such as the cardiovascular system by effecting blood pressure; and metabolic profiles by reducing lipid, glucose, insulin levels,[6][8] IGF-1[72] decreasing advanced glycation end-products levels, enhancing autophagy, increasing adiponectin levels,[40] and increasing Sirt 1 levels.[36]

A 2019 review of weight-change interventions, including alternate day fasting, time-restricted feeding, exercise and overeating, found that body weight homeostasis could not precisely correct for "energetic errors" – the loss or gain of calories – in the short-term.[74]

Intermittent feeding[edit]

As of 2019, current clinical guidelines recommend that hospitals ensure that the patients in critical health units get fed with 80–100 % of energy expenditure, the normocaloric feeding.[75] There are investigations in other feeding schemes, such as hypocaloric feeding[75] and intermittent feeding, also called bolus feeding.[76] A 2019 meta-analysis found that intermittent feeding may be more beneficial for premature infants, although better designed studies are required to devise clinical practices.[77] In adults, reviews have not found intermittent feeding to increase glucose variability or gastrointestinal intolerance.[78][79] A meta-analysis found intermittent feeding had no influence on gastric residual volumes and aspiration, pneumonia, mortality nor morbidity in people with a trauma, but increased the risk of diarrhea.[76][79] Given the lack of advantage and the increased incidence of diarrhea, European guidelines do not recommend intermittent feeding.[76][79]

Food production[edit]

Intermittent fasting, or "skip-a-day" feeding, is supposedly the most common feeding strategy for poultry in broiler breeder farms worldwide, as an alternative to adding bulky fibers to the diet to reduce growth. It is perceived as welfare-reducing and thus illegal in several European countries including Sweden. Intermittant fasting in poultry appears to increase food consumption but reduce appetitive behaviors such as foraging.[80]

History[edit]

Fasting is an ancient tradition, having been practiced by many cultures and religions over centuries.[9][81][82]

Therapeutic intermittent fasts for the treatment of obesity are investigated since at least 1915, with a renewed interest in the medical community in the 1960s after Bloom and his colleagues published an "enthusiastic report".[62][83] Intermittent fasts, or "short-term starvation periods", were ranging from 1 to 14 days in these early studies.[62][84] This enthusiasm propagated into lay magazines, which prompted researchers and clinicians to caution about the use of intermittent fasts without a medical monitoring.[85]

A modern type of intermittent fasting, the 5:2 diet, began in the United Kingdom in 2012.[86][87]

Religious fasting[edit]

Various forms of intermittent fasting exist in religious practices across the world.[2][11] Religious fasting regimens include Vrata in Hinduism, Islamic fasting (Ramadan) (Islam), Yom Kippur fasting and other Jewish fasts (Judaism), Orthodox Christian fasting, Fast Sunday (The Church of Jesus Christ of Latter-day Saints), and Buddhist fasting.[11] Certain religious fasting practices only require abstinence from certain foods, while others, like the Jewish fast on Yom Kippur, last for a short period of time and would cause negligible effects on body weight.[11]

In Buddhism, fasting is undertaken as part of the monastic training of Theravada Buddhist monks, who fast daily from noon to sunrise of the next day.[88] This daily fasting pattern may be undertaken by laypeople following the eight precepts.[89][90]

During Ramadan, Islamic practices are similar to intermittent fasting by not eating or drinking from sunrise until sunset, while permitting food intake in the morning before dawn and in the evening after dusk.[11] A meta-analysis on the health of Muslims during Ramadan shows significant weight loss during the fasting period of up to 1.51 kilograms (3.3 lb), but this weight was regained within about two weeks of Ramadan ending.[91] The analysis concluded that "Ramadan provides an opportunity to lose weight, but structured and consistent lifestyle modifications are necessary to achieve lasting weight loss."[91] One review found similarities between Ramadan and time-restricted feeding, with the main dissimilarity being the disallowance of water drinking with Islamic fasting.[4] Negative effects of Ramadan fasting include increased risk of hypoglycemia in diabetics, as well as inadequate levels of certain nutrients.[11]

Ramadan fasting disallowing fluids during the fasting period is hazardous for pregnant women, as it is associated with risks of inducing labour and causing gestational diabetes, although it does not appear to affect the child's weight.[92][93][94]

See also[edit]

References[edit]

  1. ^ a b c d e f g h i j k l St-Onge MP, Ard J, Baskin ML, Chiuve SE, Johnson HM, Kris-Etherton P, Varady K, et al. (American Heart Association Obesity Committee of the Council on Lifestyle and Cardiometabolic Health; Council on Cardiovascular Disease in the Young; Council on Clinical Cardiology; and Stroke) (February 2017). "Meal Timing and Frequency: Implications for Cardiovascular Disease Prevention: A Scientific Statement From the American Heart Association". Circulation. 135 (9): e96–e121. doi:10.1161/CIR.0000000000000476. PMID 28137935.
  2. ^ a b c d Patterson RE, Laughlin GA, LaCroix AZ, Hartman SJ, Natarajan L, Senger CM, et al. (August 2015). "Intermittent Fasting and Human Metabolic Health". Journal of the Academy of Nutrition and Dietetics. 115 (8): 1203–12. doi:10.1016/j.jand.2015.02.018. PMC 4516560. PMID 25857868.
  3. ^ a b c d Patterson RE, Sears DD (August 2017). "Metabolic Effects of Intermittent Fasting". Annual Review of Nutrition. 37 (1): 371–393. doi:10.1146/annurev-nutr-071816-064634. PMID 28715993.
  4. ^ a b Ismail S, Manaf RA, Mahmud A (June 2019). "Comparison of time-restricted feeding and Islamic fasting: a scoping review". Eastern Mediterranean Health Journal (Review). World Health Organization Regional Office for the Eastern Mediterranean. 25 (4): 239–245. doi:10.26719/emhj.19.011. PMID 31210344.
  5. ^ a b c d e f g h i Tinsley GM, La Bounty PM (October 2015). "Effects of intermittent fasting on body composition and clinical health markers in humans". Nutrition Reviews. 73 (10): 661–74. doi:10.1093/nutrit/nuv041. PMID 26374764.
  6. ^ a b c d e f g h Cioffi I, Evangelista A, Ponzo V, Ciccone G, Soldati L, Santarpia L, et al. (December 2018). "Intermittent versus continuous energy restriction on weight loss and cardiometabolic outcomes: a systematic review and meta-analysis of randomized controlled trials". Journal of Translational Medicine (Systematic review). 16 (1): 371. doi:10.1186/s12967-018-1748-4. PMC 6304782. PMID 30583725.
  7. ^ a b Sainsbury A, Wood RE, Seimon RV, Hills AP, King NA, Gibson AA, Byrne NM (December 2018). "Rationale for novel intermittent dieting strategies to attenuate adaptive responses to energy restriction". Obesity Reviews. 19 Suppl 1: 47–60. doi:10.1111/obr.12787. PMID 30511512.
  8. ^ a b c d e Harris L, Hamilton S, Azevedo LB, Olajide J, De Brún C, Waller G, et al. (February 2018). "Intermittent fasting interventions for treatment of overweight and obesity in adults: a systematic review and meta-analysis" (PDF). JBI Database of Systematic Reviews and Implementation Reports. 16 (2): 507–547. doi:10.11124/JBISRIR-2016-003248. PMID 29419624.
  9. ^ a b c d Hart K (2018). "Chapter 4.6 Fad diets and fasting for weight loss in obesity.". In Hankey C (ed.). Advanced nutrition and dietetics in obesity. Wiley. pp. 177–182. ISBN 9780470670767.
  10. ^ a b c d e f g "Calorie restriction and fasting diets: What do we know?". National Institute on Aging, US National Institutes of Health. 2018-08-14. Retrieved 29 September 2019.
  11. ^ a b c d e f Persynaki A, Karras S, Pichard C (March 2017). "Unraveling the metabolic health benefits of fasting related to religious beliefs: A narrative review". Nutrition. 35: 14–20. doi:10.1016/j.nut.2016.10.005. PMID 28241983.
  12. ^ a b "Diet Review: Intermittent Fasting for Weight Loss". The Nutrition Source. Harvard School of Public Health. 16 January 2018. Retrieved 4 October 2019.
  13. ^ a b c d e f g h i Anton SD, Moehl K, Donahoo WT, Marosi K, Lee SA, Mainous AG, et al. (February 2018). "Flipping the Metabolic Switch: Understanding and Applying the Health Benefits of Fasting". Obesity (Review). 26 (2): 254–268. doi:10.1002/oby.22065. PMC 5783752. PMID 29086496. Lay summary.
  14. ^ a b c d Johnstone, A (May 2015). "Fasting for weight loss: an effective strategy or latest dieting trend?". International Journal of Obesity (Review). 39 (5): 727–33. doi:10.1038/ijo.2014.214. PMID 25540982.
  15. ^ a b c Mattson MP, Longo VD, Harvie M (October 2017). "Impact of intermittent fasting on health and disease processes". Ageing Research Reviews. 39: 46–58. doi:10.1016/j.arr.2016.10.005. PMC 5411330. PMID 27810402.
  16. ^ "Time-restricted eating is growing in popularity, but is it healthy?". www.heart.org. Retrieved 4 October 2019.
  17. ^ a b Evert AB, Dennison M, Gardner CD, Garvey WT, Lau KH, MacLeod J, et al. (May 2019). "Nutrition Therapy for Adults With Diabetes or Prediabetes: A Consensus Report". Diabetes Care (Professional society guidelines). 42 (5): 731–754. doi:10.2337/dci19-0014. PMID 31000505.
  18. ^ a b Minister of Health NZ (2017). Clinical guidelines for weight management in New Zealand adults (National guidelines). ISBN 978-1-98-853916-4.
  19. ^ "Popular diets review". Ministry of Health NZ (National guidelines). February 2018. Retrieved 1 November 2019.
  20. ^ Arbolario K (26 August 2019). "Intermittent Fasting: Exposing The Dangers Of This Fad Diet". Medical Daily. Intermittent fasting is all the rage these days when it comes to the weight loss and fitness community. Given the large number of people including celebrities who swear by it, it’s not surprising why this diet is getting a lot of attention.
  21. ^ "How to diet". Live Well - NHS Choices. UK National Health Service. 9 December 2011. Retrieved 10 February 2014.
  22. ^ Trueland J (December 2013). "Fast and effective?". Nursing Standard. 28 (16–18): 26–7. doi:10.7748/ns2013.12.28.16.26.s28. PMID 24345130.
  23. ^ Mosley, Michael (5 September 2012). "Eat, Fast & Live Longer". Horizon. Episode 49x03. BBC. 2. Retrieved 10 February 2014.
  24. ^ a b Fleming, Amy (27 January 2015). "Fasting facts: is the 5:2 diet too good to be true?". The Guardian. Retrieved 18 January 2018.
  25. ^ "The UK's Hot New 5:2 Diet Craze Hits The U.S. - Weight Loss Miracle?". Forbes. 17 May 2013. Retrieved 10 February 2014.
  26. ^ a b Solon O (2017-09-04). "The Silicon Valley execs who don't eat for days: 'It's not dieting, it's biohacking'". The Guardian. Retrieved 2018-11-05.
  27. ^ Kohok, Shivaani (3 June 2019). "Why is intermittent fasting so popular?".
  28. ^ "2018 Food & Health Survey" (PDF). foodinsight.org. International Food Information Council. 2018.
  29. ^ "News analysis: Does the 5:2 intermittent fasting diet work?". Health News. UK National Health Service - NHS Choices. May 2013. Retrieved 23 November 2016.
  30. ^ Collier R (June 2013). "Intermittent fasting: the science of going without". CMAJ. 185 (9): E363–4. doi:10.1503/cmaj.109-4451. PMC 3680567. PMID 23569168.
  31. ^ a b Giles T (24 April 2018). "Silicon Valley wants to cash in on fasting". Bloomberg News. Retrieved 8 November 2018.
  32. ^ "Not so fast: Pros and cons of the newest diet trend". Harvard Health Publishing, Harvard University Medical School. 31 July 2019. Retrieved 28 August 2019.
  33. ^ Davis CS, Clarke RE, Coulter SN, Rounsefell KN, Walker RE, Rauch CE, et al. (March 2016). "Intermittent energy restriction and weight loss: a systematic review". European Journal of Clinical Nutrition. 70 (3): 292–9. doi:10.1038/ejcn.2015.195. PMID 26603882.
  34. ^ a b c Freire R (July 2019). "Scientific evidence of diets for weight loss: Different macronutrient composition, intermittent fasting, and popular diets". Nutrition. 69: 110549. doi:10.1016/j.nut.2019.07.001. PMID 31525701.
  35. ^ a b c Thom G, Lean M (May 2017). "Is There an Optimal Diet for Weight Management and Metabolic Health?" (PDF). Gastroenterology (Review). 152 (7): 1739–1751. doi:10.1053/j.gastro.2017.01.056. PMID 28214525. The principle for it providing health benefit independent of body weight loss is that regularly inducing a mild stressor such as fasting increases resistance against a number of degenerative age-related problems. [...] Thus, IER is not superior to CER on average, but offers an alternative to conventional dieting approaches. [...] It would seem plausible that the unfavorable physiological changes synonymous with energy restriction and weight loss could be offset by intermittently raising energy intake to meet weight maintenance energy requirements, rather than a continuous and ongoing energy restriction. However, a systematic review of clinical trials was unable to find any evidence that IER reduced adaptive responses when compared with CER.
  36. ^ a b Ekmekcioglu, C (21 October 2019). "Nutrition and longevity - From mechanisms to uncertainties". Critical Reviews in Food Science and Nutrition (Review): 1–20. doi:10.1080/10408398.2019.1676698. PMID 31631676. Most of the IF studies were associated with weight loss in the range of approximately 2.5%–10%. Also IF resulted in favorable metabolic changes, like better insulin profiles, but also lower CRP values. [...] A 3-week alternate day fasting in 11 individuals increased SIRT1 expression in skeletal muscle.
  37. ^ Stockman, MC; Thomas, D; Burke, J; Apovian, CM (June 2018). "Intermittent Fasting: Is the Wait Worth the Weight?". Current Obesity Reports (Review). 7 (2): 172–185. doi:10.1007/s13679-018-0308-9. PMC 5959807. PMID 29700718. Nearly all IF studies have resulted in some degree of weight loss, ranging from 2.5–9.9%, and associated fat mass loss.
  38. ^ Alhamdan BA, Garcia-Alvarez A, Alzahrnai AH, Karanxha J, Stretchberry DR, Contrera KJ, et al. (September 2016). "Alternate-day versus daily energy restriction diets: which is more effective for weight loss? A systematic review and meta-analysis". Obesity Science & Practice. 2 (3): 293–302. doi:10.1002/osp4.52. PMC 5043510. PMID 27708846.
  39. ^ Roman YM, Dominguez MC, Easow TM, Pasupuleti V, White CM, Hernandez AV (October 2019). "Effects of intermittent versus continuous dieting on weight and body composition in obese and overweight people: a systematic review and meta-analysis of randomized controlled trials". International Journal of Obesity. 43 (10): 2017–2027. doi:10.1038/s41366-018-0204-0. hdl:10757/624649. PMID 30206335.
  40. ^ a b Papamichou D, Panagiotakos DB, Itsiopoulos C (June 2019). "Dietary patterns and management of type 2 diabetes: A systematic review of randomised clinical trials". Nutrition, Metabolism, and Cardiovascular Diseases (Systematic review). 29 (6): 531–543. doi:10.1016/j.numecd.2019.02.004. PMID 30952576.
  41. ^ Longo VD, Mattson MP (February 2014). "Fasting: molecular mechanisms and clinical applications". Cell Metabolism. 19 (2): 181–92. doi:10.1016/j.cmet.2013.12.008. PMC 3946160. PMID 24440038.
  42. ^ Harris L, McGarty A, Hutchison L, Ells L, Hankey C (January 2018). "Short-term intermittent energy restriction interventions for weight management: a systematic review and meta-analysis". Obesity Reviews. 19 (1): 1–13. doi:10.1111/obr.12593. PMID 28975722.
  43. ^ Headland M, Clifton PM, Carter S, Keogh JB (June 2016). "Weight-Loss Outcomes: A Systematic Review and Meta-Analysis of Intermittent Energy Restriction Trials Lasting a Minimum of 6 Months". Nutrients. 8 (6): 354. doi:10.3390/nu8060354. PMC 4924195. PMID 27338458.
  44. ^ "Réseau NACRe - Réseau National Alimentation Cancer Recherche - Rapport NACRe jeûne regimes restrictifs cancer 2017". www6.inra.fr (in French). November 2017. Retrieved 19 September 2018. Lay summary.
  45. ^ Régime et évolution d'un cancer. Rev Prescrire. 1 October 2018. p. 773.
  46. ^ "No proof 5:2 diet prevents cancer". nhs.uk. 3 October 2018.
  47. ^ Russell J, Rovere A, eds. (2009). "Fasting". American Cancer Society Complete Guide to Complementary and Alternative Cancer Therapies (2nd ed.). American Cancer Society. ISBN 9780944235713.CS1 maint: uses editors parameter (link)
  48. ^ Smith LA, O'Flanagan CH, Bowers LW, Allott EH, Hursting SD (April 2018). "Translating Mechanism-Based Strategies to Break the Obesity-Cancer Link: A Narrative Review". Journal of the Academy of Nutrition and Dietetics (Narrative review). 118 (4): 652–667. doi:10.1016/j.jand.2017.08.112. PMC 5869082. PMID 29102513.
  49. ^ O'Flanagan, CH; Smith, LA; McDonell, SB; Hursting, SD (24 May 2017). "When less may be more: calorie restriction and response to cancer therapy". BMC Medicine (Mini-review). 15 (1): 106. doi:10.1186/s12916-017-0873-x. PMC 5442682. PMID 28539118.
  50. ^ Brain K, Burrows TL, Rollo ME, Chai LK, Clarke ED, Hayes C, et al. (April 2019). "A systematic review and meta-analysis of nutrition interventions for chronic noncancer pain". Journal of Human Nutrition and Dietetics. 32 (2): 198–225. doi:10.1111/jhn.12601. PMID 30294938.
  51. ^ Fond G, Macgregor A, Leboyer M, Michalsen A (October 2013). "Fasting in mood disorders: neurobiology and effectiveness. A review of the literature" (PDF). Psychiatry Research. 209 (3): 253–8. doi:10.1016/j.psychres.2012.12.018. PMID 23332541.
  52. ^ Michalsen A (April 2010). "Prolonged fasting as a method of mood enhancement in chronic pain syndromes: a review of clinical evidence and mechanisms". Current Pain and Headache Reports. 14 (2): 80–7. doi:10.1007/s11916-010-0104-z. PMID 20425196.
  53. ^ Veronese N, Reginster JY (June 2019). "The effects of calorie restriction, intermittent fasting and vegetarian diets on bone health". Aging Clinical and Experimental Research. 31 (6): 753–758. doi:10.1007/s40520-019-01174-x. PMID 30903600.
  54. ^ Levy E, Chu T (July 2019). "Intermittent Fasting and Its Effects on Athletic Performance: A Review". Current Sports Medicine Reports. 18 (7): 266–269. doi:10.1249/JSR.0000000000000614. PMID 31283627.
  55. ^ Vieira AF, Costa RR, Macedo RC, Coconcelli L, Kruel LF (October 2016). "Effects of aerobic exercise performed in fasted v. fed state on fat and carbohydrate metabolism in adults: a systematic review and meta-analysis". The British Journal of Nutrition (Meta-analysis). 116 (7): 1153–1164. doi:10.1017/S0007114516003160. PMID 27609363. Lay summary.
  56. ^ Aird TP, Davies RW, Carson BP (May 2018). "Effects of fasted vs fed-state exercise on performance and post-exercise metabolism: A systematic review and meta-analysis". Scandinavian Journal of Medicine & Science in Sports (Meta-analysis). 28 (5): 1476–1493. doi:10.1111/sms.13054. hdl:10344/6776. PMID 29315892.
  57. ^ a b c d e Horne BD, Muhlestein JB, Anderson JL (August 2015). "Health effects of intermittent fasting: hormesis or harm? A systematic review". The American Journal of Clinical Nutrition. 102 (2): 464–70. doi:10.3945/ajcn.115.109553. PMID 26135345.
  58. ^ "Top diets review". nhs.uk. 26 April 2018. Retrieved 6 October 2019.
  59. ^ a b Freire, R (4 July 2019). "Scientific evidence of diets for weight loss: Different macronutrient composition, intermittent fasting, and popular diets". Nutrition (Burbank, Los Angeles County, Calif.) (Review). 69: 110549. doi:10.1016/j.nut.2019.07.001. PMID 31525701.
  60. ^ a b c Monnier, L; Colette, C; Lapinski, H; Boniface, H (17 February 2008). "Rationale for SMBG: lessons from the study of daytime periods by taking meals as reference". Diabetes & Metabolism (Mini-review). Elsevier Masson. 30 (2): 113–119. doi:10.1016/S1262-3636(07)70097-6. PMID 15223983.
  61. ^ a b c d e Drăgoi, Cristina Manuela (10 July 2019). "Insights into Chrononutrition: The Innermost Interplay Amongst Nutrition, Metabolism and the Circadian Clock, in the Context of Epigenetic Reprogramming". Farmacia. 67 (4): 557–571. doi:10.31925/farmacia.2019.4.2.
  62. ^ a b c Kerndt, PR; Naughton, JL; Driscoll, CE; Loxterkamp, DA (November 1982). "Fasting: the history, pathophysiology and complications". The Western Journal of Medicine (Review). 137 (5): 379–99. PMC 1274154. PMID 6758355. Metabolically, early fasting is characterized by a high rate of gluconeogenesis with amino acids as the primary substrates. As fasting continues, progressive ketosis develops due to the mobilization and oxidation of fatty acids. As ketone levels rise they replace glucose as the primary energy source in the central nervous system, thereby decreasing the need for gluconeogenesis and sparing protein catabolism. [...] Fasting as a therapy for obesity has long been advocated. Folin and Denis in 1915 recommended repeated short periods of starvation as a safe and effective method of weight reduction. In modern times Bloom, Duncan and associates and Drenick and colleagues advocated prolonged fasts for weight reduction in morbid obesity.
  63. ^ Cahill GF (August 2006). "Fuel metabolism in starvation". Annual Review of Nutrition (Narrative Review). 26 (1): 1–22. doi:10.1146/annurev.nutr.26.061505.111258. PMID 16848698. Many small points were clarified regarding adipose tissue, such as the release of free glycerol with the fatty acids mobilized during fasting. [...] Therapeutic fasting of obese subjects was in vogue in the 1950s and 1960s. In an informal conversation with Rachmiel Levine, who knew of our fasting work, it became evident that the fuel substrate for brain could not continue to be glucose since gluconeogenesis from protein would consume so much muscle that longterm viability would be dramatically decreased. [...] Hepatic glycogen contribution to blood glucose is essentially zero by the second or third day of starvation. [See also Figure 1]
  64. ^ Renold AE (1965). "Section 5: Adipose Tissue". Handbook of Physiology: a Critical, Comprehensive Presentation of Physiological Knowledge and Concepts. American Physiological Society.
  65. ^ Lechner K, von Schacky C, McKenzie AL, Worm N, Nixdorff U, Lechner B, et al. (August 2019). "Lifestyle factors and high-risk atherosclerosis: Pathways and mechanisms beyond traditional risk factors". European Journal of Preventive Cardiology: 2047487319869400. doi:10.1177/2047487319869400. PMID 31408370. Intermittent states of negative energy balance activate a set of adaptations where metabolism switches from lipid synthesis and fat storage to mobilization of fat as free fatty acids and fatty acid-derived ketones. This has been linked to improvement in surrogate markers for cardiometabolic health (e.g. weight loss) and beneficial effects on body composition such as mobilization of visceral fat and retention of lean mass.
  66. ^ Zubrzycki A, Cierpka-Kmiec K, Kmiec Z, Wronska A (October 2018). "The role of low-calorie diets and intermittent fasting in the treatment of obesity and type-2 diabetes". Journal of Physiology and Pharmacology (Review). 69 (5). doi:10.26402/jpp.2018.5.02. PMID 30683819. These beneficial effects arise not only from the loss of body mass, but also from the activation of metabolic pathways specific to fasting conditions. IF interventions induce a metabolic shift that has the potential to positively alter body composition. This switch represents a shift from preferential lipid synthesis and fat storage to the mobilization of fat. It typically occurs in the third phase of fasting (i.e., 12 – 36 hours after the last meal) when glycogen in the hepatocytes (though not in muscles) becomes depleted. Around that time, accelerated lipolysis in adipose tissue produces increased plasma levels of FFAs, which contribute to the increased synthesis of fatty acid-derived ketones in the liver, kidney, astrocytes, and enterocytes. IF regimens are a potential method of treatment for obesity and related metabolic conditions, including T2D and metabolic syndrome.
  67. ^ Elia M, Livesey G (April 1988). "Theory and validity of indirect calorimetry during net lipid synthesis". The American Journal of Clinical Nutrition. 47 (4): 591–607. doi:10.1093/ajcn/47.4.591. PMID 3281433.
  68. ^ Amaro-Gahete FJ, Sanchez-Delgado G, Jurado-Fasoli L, De-la-O A, Castillo MJ, Helge JW, Ruiz JR (July 2019). "Assessment of maximal fat oxidation during exercise: A systematic review". Scandinavian Journal of Medicine & Science in Sports (Systematic review). 29 (7): 910–921. doi:10.1111/sms.13424. PMID 30929281.
  69. ^ Ye X, Li M, Hou T, Gao T, Zhu WG, Yang Y (January 2017). "Sirtuins in glucose and lipid metabolism". Oncotarget. 8 (1): 1845–1859. doi:10.18632/oncotarget.12157. PMC 5352102. PMID 27659520.
  70. ^ Gilgenkrantz H, Perret C (March 2012). "[Sirtuin 1, hepatic steatosis and liver cancer]". Médecine Sciences. 28 (3): 269–71. doi:10.1051/medsci/2012283014. PMID 22480650.
  71. ^ Mattson MP, Moehl K, Ghena N, Schmaedick M, Cheng A (February 2018). "Intermittent metabolic switching, neuroplasticity and brain health". Nature Reviews. Neuroscience (Review). 19 (2): 63–80. doi:10.1038/nrn.2017.156. PMC 5913738. PMID 29321682.
  72. ^ a b Rahmani J, Kord Varkaneh H, Clark C, Zand H, Bawadi H, Ryan PM, et al. (August 2019). "The influence of fasting and energy restricting diets on IGF-1 levels in humans: A systematic review and meta-analysis". Ageing Research Reviews (Meta-analysis). 53: 100910. doi:10.1016/j.arr.2019.100910. PMID 31116995.
  73. ^ Seimon RV, Roekenes JA, Zibellini J, Zhu B, Gibson AA, Hills AP, et al. (December 2015). "Do intermittent diets provide physiological benefits over continuous diets for weight loss? A systematic review of clinical trials" (PDF). Molecular and Cellular Endocrinology (Systematic review). 418 Pt 2: 153–72. doi:10.1016/j.mce.2015.09.014. PMID 26384657.
  74. ^ Levitsky DA, Sewall A, Zhong Y, Barre L, Shoen S, Agaronnik N, et al. (February 2019). "Quantifying the imprecision of energy intake of humans to compensate for imposed energetic errors: A challenge to the physiological control of human food intake". Appetite. 133: 337–343. doi:10.1016/j.appet.2018.11.017. PMID 30476522.
  75. ^ a b Marik PE, Hooper MH (March 2016). "Normocaloric versus hypocaloric feeding on the outcomes of ICU patients: a systematic review and meta-analysis". Intensive Care Medicine. 42 (3): 316–323. doi:10.1007/s00134-015-4131-4. PMID 26556615.
  76. ^ a b c Singer P, Blaser AR, Berger MM, Alhazzani W, Calder PC, Casaer MP, et al. (February 2019). "ESPEN guideline on clinical nutrition in the intensive care unit". Clinical Nutrition. 38 (1): 48–79. doi:10.1016/j.clnu.2018.08.037. PMID 30348463.
  77. ^ Wang Y, Zhu W, Luo BR (October 2019). "Continuous feeding versus intermittent bolus feeding for premature infants with low birth weight: a meta-analysis of randomized controlled trials". European Journal of Clinical Nutrition (Meta-analysis). doi:10.1038/s41430-019-0522-x. PMID 31659243.
  78. ^ Bear DE, Hart N, Puthucheary Z (August 2018). "Continuous or intermittent feeding: pros and cons". Current Opinion in Critical Care (Review). 24 (4): 256–261. doi:10.1097/MCC.0000000000000513. PMID 29877877.
  79. ^ a b c Van Dyck L, Casaer MP (August 2019). "Intermittent or continuous feeding: any difference during the first week?". Current Opinion in Critical Care (Meta-analysis). 25 (4): 356–362. doi:10.1097/MCC.0000000000000617. PMID 31107308.
  80. ^ Lindholm, Caroline (2019). Intermittent fasting in chickens: Physiological mechanisms and welfare implications for broiler breeders. Linköping University Electronic Press. ISBN 978-91-7685-018-3.
  81. ^ Fung J (11 April 2015). "Fasting - A History". Intensive Dietary Management.
  82. ^ Hicks C (13 April 2015). "Why fasting is now back in fashion". The Telegraph. Retrieved 14 January 2019.
  83. ^ Howard, A. N. (1975). "Dietary Treatment of Obesity". Obesity: Its Pathogenesis And Management (Monograph). Springer Netherlands. pp. 123–153. doi:10.1007/978-94-011-7155-7_5. ISBN 978-94-011-7155-7. Modern work stems from the enthusiastic report of Bloom on the use of starvation therapy, which stimulated many other workers to examine this type of treatment and the subject has been extensively reviewed. The idea is not new and dates back to at least 1915.:125
  84. ^ Duncan, Garfield G.; Cristofori, Fred C.; Yue, James K.; Murthy, M.S.J. (September 1964). "The Control of Obesity by Intermittent Fasts". Medical Clinics of North America (Review). 48 (5): 1359–1372. doi:10.1016/S0025-7125(16)33406-X.
  85. ^ Dinning, JS (October 1963). "Correction Of Obesity By Fasting". Nutrition Reviews (Mini-review). 21 (10): 304–6. doi:10.1111/j.1753-4887.1963.tb07474.x. PMID 14069065.
  86. ^ Michael Mosley (5 August 2012). "The power of intermittent fasting". BBC Health. Retrieved 14 January 2019.
  87. ^ "Horizon - Eat, Fast and Live Longer". BBC iPlayer. 6 August 2012. Retrieved 14 January 2019.
  88. ^ Johnston WM (2013-12-04). Encyclopedia of Monasticism. Routledge. p. 467. ISBN 9781136787164.
  89. ^ Cottrell T, Zigmond D (2016-09-06). Buddha's Diet: The Ancient Art of Losing Weight Without Losing Your Mind. Running Press. pp. 26–27. ISBN 9780762460465.
  90. ^ Johnston WM (2013-12-04). Encyclopedia of Monasticism. Routledge. p. 467. ISBN 9781136787164.
  91. ^ a b Sadeghirad B, Motaghipisheh S, Kolahdooz F, Zahedi MJ, Haghdoost AA (February 2014). "Islamic fasting and weight loss: a systematic review and meta-analysis". Public Health Nutrition. 17 (2): 396–406. doi:10.1017/S1368980012005046. PMID 23182306.
  92. ^ Glazier JD, Hayes DJ, Hussain S, D'Souza SW, Whitcombe J, Heazell AE, Ashton N (October 2018). "The effect of Ramadan fasting during pregnancy on perinatal outcomes: a systematic review and meta-analysis". BMC Pregnancy and Childbirth. 18 (1): 421. doi:10.1186/s12884-018-2048-y. PMC 6202808. PMID 30359228.
  93. ^ Balani J, Hyer S, Wagner M, Shehata H (2013). "Chapter 22: Obesity, Polycystic Ovaries and Impaired Reproductive Outcome". In Mahmood T, Arulkumaran S (eds.). Obesity. Elsevier. pp. 289–298. doi:10.1016/B978-0-12-416045-3.00022-4. ISBN 978-0-12-416045-3.
  94. ^ Mirghani HM, Hamud OA (January 2006). "The effect of maternal diet restriction on pregnancy outcome". American Journal of Perinatology. 23 (1): 21–4. doi:10.1055/s-2005-923435. PMID 16450268.

External links[edit]