Fasting

This page features 50 unique references to scientific papers.


Research analysis by and verified by the Examine.com Research Team. Last updated on Apr 18, 2018.

Summary of Fasting

Primary Information, Benefits, Effects, and Important Facts

In Progress


This page on Fasting is currently marked as in-progress. We are still compiling research.



The physiology of fasting

Metabolism (phases I, II, III)

Substrate utilization

Glycogen, glucose, fatty acids, glycerol, ketones, triglycerides, cholesterol, amino acids, ammonia / urea / uric acid

Hormonal change

Insulin, glucagon, glucocorticoids, thyroid hormones, GI peptides, adiponectin, leptin, ghrelin, catecholamines

Nutrient / energy sensing

AMP / ADP / ATP / AMPK / mTOR

Autophagy

Why and when do animals fast?

Seasonal (hibernation / aestivation), natural period in life (migration / molting / reproduction / development), food shortage, feeding tactics (sit-and-wait)

Evolutionary considerations for humans and fasting

Body composition

Effects on fat-free mass, fat mass, and water balance

Immune system

Effects on innate and adaptive immunity

Adjunct to cancer treatment

Athletic performance

Neurology

Effects on cognitive function and neurodegeneration

Microbiome

Changes with fasting and refeeding

Gene expression (might be more appropriate within each section)

Longevity

Frequently Asked Questions

Questions and answers regarding Fasting

Q: Do I need to eat six times a day to keep my metabolism high?

A: Eating food six times a day, or very high meal frequency, does not seem to increase the overall metabolic rate more than simply eating three times a day. If such a meal frequency can help you feel better on a diet then it can be useful but it alone won't cause weight loss or prevent weight gain.

Read full answer to "Do I need to eat six times a day to keep my metabolism high?"


Q: Could fasting help treat MS symptoms?

A: We analyze a study that says fasting could help with MS.

Read full answer to "Could fasting help treat MS symptoms?"


Q: Is it really that bad to skip breakfast?

Read full answer to "Is it really that bad to skip breakfast?"


Q: The lowdown on intermittent fasting

A: We analyze the research on intermittent fasting and how it impacts your health.

Read full answer to "The lowdown on intermittent fasting"


Scientific Support & Reference Citations

Via HEM and FAQ:

  1. Bellisle F, McDevitt R, Prentice AM. Meal frequency and energy balance. Br J Nutr. (1997)
  2. Palmer MA, Capra S, Baines SK. Association between eating frequency, weight, and health. Nutr Rev. (2009)
  3. Leidy HJ, Campbell WW. The effect of eating frequency on appetite control and food intake: brief synopsis of controlled feeding studies. J Nutr. (2011)
  4. Taylor MA, Garrow JS. Compared with nibbling, neither gorging nor a morning fast affect short-term energy balance in obese patients in a chamber calorimeter. Int J Obes Relat Metab Disord. (2001)
  5. Verboeket-van de Venne WP, Westerterp KR. Influence of the feeding frequency on nutrient utilization in man: consequences for energy metabolism. Eur J Clin Nutr. (1991)
  6. Smeets AJ, Westerterp-Plantenga MS. Acute effects on metabolism and appetite profile of one meal difference in the lower range of meal frequency. Br J Nutr. (2008)
  7. Cameron JD, Cyr MJ, Doucet E. Increased meal frequency does not promote greater weight loss in subjects who were prescribed an 8-week equi-energetic energy-restricted diet. Br J Nutr. (2010)
  8. Verboeket-van de Venne WP, Westerterp KR. Frequency of feeding, weight reduction and energy metabolism. Int J Obes Relat Metab Disord. (1993)
  9. Munsters MJ, Saris WH. Effects of meal frequency on metabolic profiles and substrate partitioning in lean healthy males. PLoS One. (2012)
  10. Pearcey SM, de Castro JM. Food intake and meal patterns of weight-stable and weight-gaining persons. Am J Clin Nutr. (2002)
  11. Webber J, Macdonald IA. The cardiovascular, metabolic and hormonal changes accompanying acute starvation in men and women. Br J Nutr. (1994)
  12. Mansell PI, Fellows IW, Macdonald IA. Enhanced thermogenic response to epinephrine after 48-h starvation in humans. Am J Physiol. (1990)
  13. Heilbronn LK, et al. Alternate-day fasting in nonobese subjects: effects on body weight, body composition, and energy metabolism. Am J Clin Nutr. (2005)
  14. Zerguini Y, et al. Influence of Ramadan fasting on physiological and performance variables in football players: summary of the F-MARC 2006 Ramadan fasting study. J Sports Sci. (2008)
  15. Chennaoui M, et al. Effects of Ramadan fasting on physical performance and metabolic, hormonal, and inflammatory parameters in middle-distance runners. Appl Physiol Nutr Metab. (2009)
  16. Sadiya A, et al. Effect of Ramadan fasting on metabolic markers, body composition, and dietary intake in Emiratis of Ajman (UAE) with metabolic syndrome. Diabetes Metab Syndr Obes. (2011)
  17. Shariatpanahi ZV, et al. Effect of Ramadan fasting on some indices of insulin resistance and components of the metabolic syndrome in healthy male adults. Br J Nutr. (2008)
  18. Yarahmadi Sh, et al. Metabolic and clinical effects of Ramadan fasting in patients with type II diabetes. J Coll Physicians Surg Pak. (2003)
  19. Bouguerra R, et al. {Metabolic effects of the month of Ramadan fasting on type 2 diabetes}. East Mediterr Health J. (2003)
  20. Food intake patterns and body mass index in observational studies.
  21. Bertéus Forslund H, et al. Meal patterns and obesity in Swedish women-a simple instrument describing usual meal types, frequency and temporal distribution. Eur J Clin Nutr. (2002)
  22. Drummond SE, et al. Evidence that eating frequency is inversely related to body weight status in male, but not female, non-obese adults reporting valid dietary intakes. Int J Obes Relat Metab Disord. (1998)
  23. International Society of Sports Nutrition position stand: meal frequency.
  24. Observational Studies Refuting the Effectiveness of Increased Meal Frequency on Weight loss/Fat loss.
  25. Titan SM, et al. Frequency of eating and concentrations of serum cholesterol in the Norfolk population of the European prospective investigation into cancer (EPIC-Norfolk): cross sectional study. BMJ. (2001)
  26. Howarth NC, et al. Eating patterns and dietary composition in relation to BMI in younger and older adults. Int J Obes (Lond). (2007)
  27. Duval K, et al. Physical activity is a confounding factor of the relation between eating frequency and body composition. Am J Clin Nutr. (2008)
  28. Weinsier RL, et al. Metabolic predictors of obesity. Contribution of resting energy expenditure, thermic effect of food, and fuel utilization to four-year weight gain of post-obese and never-obese women. J Clin Invest. (1995)
  29. Saris WH. Fit, fat and fat free: the metabolic aspects of weight control. Int J Obes Relat Metab Disord. (1998)
  30. Farshchi HR, Taylor MA, Macdonald IA. Decreased thermic effect of food after an irregular compared with a regular meal pattern in healthy lean women. Int J Obes Relat Metab Disord. (2004)
  31. Farshchi HR, Taylor MA, Macdonald IA. Beneficial metabolic effects of regular meal frequency on dietary thermogenesis, insulin sensitivity, and fasting lipid profiles in healthy obese women. Am J Clin Nutr. (2005)
  32. Yannakoulia M, et al. Association of eating frequency with body fatness in pre- and postmenopausal women. Obesity (Silver Spring). (2007)
  33. Adechian S, et al. Protein feeding pattern, casein feeding or milk soluble protein feeding did not change the evolution of body composition during a short-term weight loss program. Am J Physiol Endocrinol Metab. (2012)
  34. Solomon TP, et al. The effect of feeding frequency on insulin and ghrelin responses in human subjects. Br J Nutr. (2008)
  35. Szajewska H, Ruszczynski M. Systematic review demonstrating that breakfast consumption influences body weight outcomes in children and adolescents in Europe. Crit Rev Food Sci Nutr. (2010)
  36. Reeves S, et al. Experimental manipulation of breakfast in normal and overweight/obese participants is associated with changes to nutrient and energy intake consumption patterns. Physiol Behav. (2014)
  37. Geliebter A, et al. Skipping breakfast leads to weight loss but also elevated cholesterol compared with consuming daily breakfasts of oat porridge or frosted cornflakes in overweight individuals: a randomised controlled trial. J Nutr Sci. (2014)
  38. Betts JA, et al. The causal role of breakfast in energy balance and health: a randomized controlled trial in lean adults. Am J Clin Nutr. (2014)
  39. Jakubowicz D, et al. Fasting until noon triggers increased postprandial hyperglycemia and impaired insulin response after lunch and dinner in individuals with type 2 diabetes: a randomized clinical trial. Diabetes Care. (2015)
  40. LeCheminant GM, et al. A randomized controlled trial to study the effects of breakfast on energy intake, physical activity, and body fat in women who are nonhabitual breakfast eaters. Appetite. (2017)
  41. Clayton DJ, James LJ. The effect of breakfast on appetite regulation, energy balance and exercise performance. Proc Nutr Soc. (2016)
  42. Moro T, et al. Effects of eight weeks of time-restricted feeding (16/8) on basal metabolism, maximal strength, body composition, inflammation, and cardiovascular risk factors in resistance-trained males. J Transl Med. (2016)
  43. Farshchi HR, Taylor MA, Macdonald IA. Deleterious effects of omitting breakfast on insulin sensitivity and fasting lipid profiles in healthy lean women. Am J Clin Nutr. (2005)
  44. Mattson MP, Longo VD, Harvie M. Impact of intermittent fasting on health and disease processes. Ageing Res Rev. (2016)
  45. Tinsley GM, La Bounty PM. Effects of intermittent fasting on body composition and clinical health markers in humans. Nutr Rev. (2015)
  46. Longo VD, Mattson MP. Fasting: molecular mechanisms and clinical applications. Cell Metab. (2014)
  47. Masoro EJ. Overview of caloric restriction and ageing. Mech Ageing Dev. (2005)
  48. Mattison JA, et al. Impact of caloric restriction on health and survival in rhesus monkeys from the NIA study. Nature. (2012)
  49. Horne BD, Muhlestein JB, Anderson JL. Health effects of intermittent fasting: hormesis or harm? A systematic review. Am J Clin Nutr. (2015)
  50. Wei M, et al. Fasting-mimicking diet and markers/risk factors for aging, diabetes, cancer, and cardiovascular disease. Sci Transl Med. (2017)