Dietary fibre in gastrointestinal health and disease


Epidemiological studies have consistently demonstrated the benefits of dietary fibre on gastrointestinal health through consumption of unrefined whole foods, such as wholegrains, legumes, vegetables and fruits. Mechanistic studies and clinical trials on isolated and extracted fibres have demonstrated promising regulatory effects on the gut (for example, digestion and absorption, transit time, stool formation) and microbial effects (changes in gut microbiota composition and fermentation metabolites) that have important implications for gastrointestinal disorders. In this Review, we detail the major physicochemical properties and functional characteristics of dietary fibres, the importance of dietary fibres and current evidence for their use in the management of gastrointestinal disorders. It is now well-established that the physicochemical properties of different dietary fibres (such as solubility, viscosity and fermentability) vary greatly depending on their origin and processing and are important determinants of their functional characteristics and clinical utility. Although progress in understanding these relationships has uncovered potential therapeutic opportunities for dietary fibres, many clinical questions remain unanswered such as clarity on the optimal dose, type and source of fibre required in both the management of clinical symptoms and the prevention of gastrointestinal disorders. The use of novel fibres and/or the co-administration of fibres is an additional therapeutic approach yet to be extensively investigated.

Key points

  • Dietary fibre has been shown to have a number of important associations with the development and management of various diseases and with mortality in epidemiological and interventional studies.

  • Dietary fibre has physicochemical characteristics (for example, solubility, viscosity, fermentability) that determine its functionality in the gastrointestinal tract, including its effects on, for example, micronutrient availability, gut transit time, stool formation and microbial specificity.

  • Current dietary fibre recommendations are often limited and conflicting, and fail to provide specific types and doses in the treatment of gastrointestinal disorders including irritable bowel syndrome, inflammatory bowel disease, diverticular disease and functional constipation.

  • Future research that considers the influence of differing physicochemical characteristics on functionality will potentially maximize the effect of clinically meaningful symptom improvement in gastrointestinal disorders.

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Fig. 1: Physicochemical characteristics of dietary fibre and their location within the plant cell.
Fig. 2: Mechanisms by which different dietary fibres affect the gastrointestinal tract.
Fig. 3: Spectrum of physicochemical characteristics of dietary fibre.


  1. 1.

    Hipsley, E. H. Dietary “fibre” and pregnancy toxaemia. Br. Med. J. 2, 420–422 (1953).

    CAS  PubMed  PubMed Central  Google Scholar 

  2. 2.

    Trowell, H. et al. Letter: Dietary fibre redefined. Lancet 1, 967 (1976).

    CAS  PubMed  Google Scholar 

  3. 3.

    Scientific Advisory Committee on Nutrition. Carbohydrates and Health (2015).

  4. 4.

    Reynolds, A. et al. Carbohydrate quality and human health: a series of systematic reviews and meta-analyses. Lancet 393, 434–445 (2019).

    CAS  PubMed  Google Scholar 

  5. 5.

    EC. Regulation (EU) No 1169/2011 of the European Parliament and of the Council of 25 October 2011 on the provision of food information to consumers, amending Regulations (EC) No 1924/2006 and (EC) No 1925/2006 of the European Parliament and of the Council, and repealing Commission Directive 87/250/EEC, Council Directive 90/496/EEC, Commission Directive 1999/10/EC, Directive 2000/13/EC of the European Parliament and of the Council, Commission Directives 2002/67/EC and 2008/5/EC and Commission Regulation (EC) No 608/2004 (Text with EEA relevance). Off. J. Eur. Union 20, 168–213 (2011).

    Google Scholar 

  6. 6.

    Office of the Federal Register. Federal Register 81, 33581–34240 (2016).

  7. 7.

    Mayor, S. Eating more fibre linked to reduced risk of non-communicable diseases and death, review finds. BMJ 364, l159 (2019).

    Google Scholar 

  8. 8.

    National Institute for Health and Care Excellence. Irritable bowel syndrome in adults: diagnosis and management (NICE, 2017).

  9. 9.

    McKenzie, Y. A. et al. British Dietetic Association systematic review and evidence-based practice guidelines for the dietary management of irritable bowel syndrome in adults (2016 update). J. Hum. Nutr. Diet. 29, 549–575 (2016).

    CAS  PubMed  Google Scholar 

  10. 10.

    Lamb, C. A. et al. British Society of Gastroenterology consensus guidelines on the management of inflammatory bowel disease in adults. Gut 68, s1–s106 (2019).

    PubMed  PubMed Central  Google Scholar 

  11. 11.

    National Institute for Health and Care Excellence. Diverticular disease: diagnosis and management. (NICE, 2019).

  12. 12.

    World Gastroenterology Organisation WGO Practice Guideline – Diet and the Gut (WGO, 2018).

  13. 13.

    National Institute for Health and Care Excellence. Constipation: management. (NICE, 2020).

  14. 14.

    Jarvis, M. C. Plant cell walls: supramolecular assemblies. Food Hydrocoll. 25, 257–262 (2011).

    CAS  Google Scholar 

  15. 15.

    Grundy, M. M. L. et al. Re-evaluation of the mechanisms of dietary fibre and implications for macronutrient bioaccessibility, digestion and postprandial metabolism. Br. J. Nutr. 116, 816–833 (2016).

    CAS  PubMed  PubMed Central  Google Scholar 

  16. 16.

    Carmody, R. N. et al. Cooking shapes the structure and function of the gut microbiome. Nat. Microbiol. 4, 2052–2063 (2019).

    PubMed  PubMed Central  Google Scholar 

  17. 17.

    Lockyer, S. & Nugent, A. P. Health effects of resistant starch. Nutr. Bull. 42, 10–41 (2017).

    Google Scholar 

  18. 18.

    Lovegrove, A. et al. Role of polysaccharides in food, digestion, and health. Crit. Rev. Food Sci. Nutr. 57, 237–253 (2017).

    CAS  PubMed  Google Scholar 

  19. 19.

    Sikora, P., Tosh, S. M., Brummer, Y. & Olsson, O. Identification of high β-glucan oat lines and localization and chemical characterization of their seed kernel β-glucans. Food Chem. 137, 83–91 (2013).

    CAS  PubMed  Google Scholar 

  20. 20.

    Ngouémazong, D. E. et al. Quantifying structural characteristics of partially de-esterified pectins. Food Hydrocoll. 25, 434–443 (2011).

    Google Scholar 

  21. 21.

    Nasatto, P. L. et al. Methylcellulose, a cellulose derivative with original physical properties and extended applications. Polymers 7, 777–803 (2015).

    CAS  Google Scholar 

  22. 22.

    Cummings, J. H. & Stephen, A. M. Carbohydrate terminology and classification. Eur. J. Clin. Nutr. 61, S5–S18 (2007).

    CAS  PubMed  Google Scholar 

  23. 23.

    Food and Agriculture Organization. Food energy – methods of analysis and conversion factors. Report of a Technical Workshop no. 77. (FAO, Rome, 2003).

  24. 24.

    Renard, C. M. G. C., Crepeau, M. J. & Thibault, J. F. Influence of ionic strength, pH and dielectric constant on hydration properties of native and modified fibres from sugar-beet and wheat bran. Ind. Crop. Prod. 3, 75–84 (1994).

    CAS  Google Scholar 

  25. 25.

    Fleury, N. & Lahaye, M. Chemical and physico-chemical characterisation of fibres from Laminaria digitata (kombu breton): a physiological approach. J. Sci. Food Agric. 55, 389–400 (1991).

    CAS  Google Scholar 

  26. 26.

    Gibb, R. D., McRorie, J. W. Jr., Russell, D. A., Hasselblad, V. & D’Alessio, D. A. Psyllium fiber improves glycemic control proportional to loss of glycemic control: a meta-analysis of data in euglycemic subjects, patients at risk of type 2 diabetes mellitus, and patients being treated for type 2 diabetes mellitus. Am. J. Clin. Nutr. 102, 1604–1614 (2015).

    CAS  PubMed  Google Scholar 

  27. 27.

    Dhital, S., Gidley, M. J. & Warren, F. J. Inhibition of α-amylase activity by cellulose: kinetic analysis and nutritional implications. Carbohydr. Polym. 123, 305–312 (2015).

    CAS  PubMed  Google Scholar 

  28. 28.

    Takahashi, T., Karita, S., Ogawa, N. & Goto, M. Crystalline cellulose reduces plasma glucose concentrations and stimulates water absorption by increasing the digesta viscosity in rats. J. Nutr. 135, 2405–2410 (2005).

    CAS  PubMed  Google Scholar 

  29. 29.

    Ratanpaul, V., Williams, B. A., Black, J. L. & Gidley, M. J. Review: Effects of fibre, grain starch digestion rate and the ileal brake on voluntary feed intake in pigs. Animal 13, 2745–2754 (2019).

    CAS  PubMed  Google Scholar 

  30. 30.

    Dikeman, C. L. & Fahey, G. C. Viscosity as related to dietary fiber: a review. Crit. Rev. Food Sci. Nutr. 46, 649–663 (2006).

    CAS  PubMed  Google Scholar 

  31. 31.

    Gawkowska, D., Cybulska, J. & Zdunek, A. Structure-related gelling of pectins and linking with other natural compounds: a review. Polymers. 10, 762 (2018).

    PubMed Central  Google Scholar 

  32. 32.

    Morris, E. R. in Dietary Fibre — A Component of Food. (eds Schweizer, T. F. & Edwards, C. A.) 41–56 (Springer, 1992).

  33. 33.

    Morris, E. R. in Advanced Dietary Fibre Technology Ch. 4 (eds McCleary, B. V. & Prosky, L.) (Blackwell Science Ltd, 2001).

  34. 34.

    Müller, M., Canfora, E. E. & Blaak, E. E. Gastrointestinal transit time, glucose homeostasis and metabolic health: modulation by dietary fibers. Nutrients 10, 275 (2018).

    PubMed Central  Google Scholar 

  35. 35.

    Chutkan, R., Fahey, G., Wright, W. L. & McRorie, J. Viscous versus nonviscous soluble fiber supplements: mechanisms and evidence for fiber-specific health benefits. J. Am. Acad. Nurse Pract. 24, 476–487 (2012).

    PubMed  Google Scholar 

  36. 36.

    Vuksan, V. et al. Viscosity rather than quantity of dietary fibre predicts cholesterol-lowering effect in healthy individuals. Br. J. Nutr. 106, 1349–1352 (2011).

    CAS  PubMed  Google Scholar 

  37. 37.

    Topping, D. L., Oakenfull, D., Trimble, R. P. & Illman, R. J. A viscous fibre (methylcellulose) lowers blood glucose and plasma triacylglycerols and increases liver glycogen independently of volatile fatty acid production in the rat. Br. J. Nutr. 59, 21–30 (1988).

    CAS  PubMed  Google Scholar 

  38. 38.

    Anderson, J. W. et al. Cholesterol-lowering effects of psyllium intake adjunctive to diet therapy in men and women with hypercholesterolemia: meta-analysis of 8 controlled trials. Am. J. Clin. Nutr. 71, 472–479 (2000).

    CAS  PubMed  Google Scholar 

  39. 39.

    Bergmann, J. F. et al. Correlation between echographic gastric emptying and appetite: influence of psyllium. Gut 33, 1042–1043 (1992).

    CAS  PubMed  PubMed Central  Google Scholar 

  40. 40.

    Fabek, H., Messerschmidt, S., Brulport, V. & Goff, H. D. The effect of in vitro digestive processes on the viscosity of dietary fibres and their influence on glucose diffusion. Food Hydrocoll. 35, 718–726 (2014).

    CAS  Google Scholar 

  41. 41.

    EFSA Panel on Dietetic Products, Nutrition and Allergies. Scientific opinion on the substantiation of a health claim related to barley beta-glucans and lowering of blood cholesterol and reduced risk of (coronary) heart disease pursuant to Article 14 of Regulation (EC) No 1924/2006. EFSA J. 9, 2470 (2011).

    Google Scholar 

  42. 42.

    Degirolamo, C., Modica, S., Palasciano, G. & Moschetta, A. Bile acids and colon cancer: solving the puzzle with nuclear receptors. Trends Mol. Med. 17, 564–572 (2011).

    CAS  PubMed  Google Scholar 

  43. 43.

    Zacherl, C., Eisner, P. & Engel, K.-H. In vitro model to correlate viscosity and bile acid-binding capacity of digested water-soluble and insoluble dietary fibres. Food Chem. 126, 423–428 (2011).

    CAS  Google Scholar 

  44. 44.

    Oh, H. et al. Different dietary fibre sources and risks of colorectal cancer and adenoma: a dose–response meta-analysis of prospective studies. Br. J. Nutr. 122, 605–615 (2019).

    CAS  PubMed  Google Scholar 

  45. 45.

    Qi, J. et al. Cellulosic fraction of rice bran fibre alters the conformation and inhibits the activity of porcine pancreatic lipase. J. Funct. Foods 19, 39–48 (2015).

    CAS  Google Scholar 

  46. 46.

    Leng-Peschlow, E. Interference of dietary fibres with gastrointestinal enzymes in vitro. Digestion 44, 200–210 (1989).

    CAS  PubMed  Google Scholar 

  47. 47.

    Mackie, A. R. et al. Sodium alginate decreases the permeability of intestinal mucus. Food Hydrocoll. 52, 749–755 (2016).

    CAS  PubMed  PubMed Central  Google Scholar 

  48. 48.

    Mackie, A., Rigby, N., Harvey, P. & Bajka, B. Increasing dietary oat fibre decreases the permeability of intestinal mucus. J. Funct. Foods 26, 418–427 (2016).

    CAS  PubMed  PubMed Central  Google Scholar 

  49. 49.

    Fåk, F. et al. The physico-chemical properties of dietary fibre determine metabolic responses, short-chain fatty acid profiles and gut microbiota composition in rats fed low- and high-fat diets. PLoS ONE 10, e0127252 (2015).

    PubMed  PubMed Central  Google Scholar 

  50. 50.

    De Filippo, C. et al. Impact of diet in shaping gut microbiota revealed by a comparative study in children from Europe and rural Africa. Proc. Natl Acad. Sci. USA 107, 14691–14696 (2010).

    PubMed  Google Scholar 

  51. 51.

    Clemente, J. C. et al. The microbiome of uncontacted Amerindians. Sci Adv. 1, e1500183 (2015).

    PubMed  PubMed Central  Google Scholar 

  52. 52.

    Martinez, I. et al. The gut microbiota of rural Papua New Guineans: composition, diversity patterns, and ecological processes. Cell Rep. 11, 527–538 (2015).

    CAS  PubMed  Google Scholar 

  53. 53.

    Schnorr, S. L. et al. Gut microbiome of the Hadza hunter-gatherers. Nat. Commun. 5, 3654 (2014).

    CAS  PubMed  PubMed Central  Google Scholar 

  54. 54.

    Smits, S. A. et al. Seasonal cycling in the gut microbiome of the Hadza hunter-gatherers of Tanzania. Science 357, 802–806 (2017).

    CAS  PubMed  PubMed Central  Google Scholar 

  55. 55.

    Yatsunenko, T. et al. Human gut microbiome viewed across age and geography. Nature 486, 222–227 (2012).

    CAS  PubMed  PubMed Central  Google Scholar 

  56. 56.

    El Kaoutari, A., Armougom, F., Gordon, J. I., Raoult, D. & Henrissat, B. The abundance and variety of carbohydrate-active enzymes in the human gut microbiota. Nat. Rev. Microbiol. 11, 497–504 (2013).

    CAS  PubMed  Google Scholar 

  57. 57.

    Ze, X., Duncan, S. H., Louis, P. & Flint, H. J. Ruminococcus bromii is a keystone species for the degradation of resistant starch in the human colon. ISME J. 6, 1535–1543 (2012).

    CAS  PubMed  PubMed Central  Google Scholar 

  58. 58.

    Stephen, A. M. et al. Dietary fibre in Europe: current state of knowledge on definitions, sources, recommendations, intakes and relationships to health. Nutr. Res. Rev. 30, 149–190 (2017).

    CAS  PubMed  Google Scholar 

  59. 59.

    McRorie, J. Clinical data support that psyllium is not fermented in the gut. Am. J. Gastroenterol. 108, 1541 (2013).

    PubMed  Google Scholar 

  60. 60.

    Yao, C. K. et al. Poor reproducibility of breath hydrogen testing: implications for its application in functional bowel disorders. U Eur. Gastroenterol. J. 5, 284–292 (2017).

    CAS  Google Scholar 

  61. 61.

    Spiller, R. & Marciani, L. Intraluminal impact of food: new insights from MRI. Nutrients 11, 1147 (2019).

    CAS  PubMed Central  Google Scholar 

  62. 62.

    Major, G. et al. Demonstration of differences in colonic volumes, transit, chyme consistency, and response to psyllium between healthy and constipated subjects using magnetic resonance imaging. Neurogastroenterol. Motil. 30, e13400 (2018).

    CAS  PubMed  Google Scholar 

  63. 63.

    Gunn, D. et al. Contrasting effects of viscous and particulate fibers on colonic fermentation in vitro and in vivo, and their impact on intestinal water studied by MRI in a randomized trial. Am. J. Clin. Nutr. 112, 595–602 (2020).

    PubMed  Google Scholar 

  64. 64.

    Cuervo, A., Salazar, N., Ruas-Madiedo, P., Gueimonde, M. & Gonzalez, S. Fiber from a regular diet is directly associated with fecal short-chain fatty acid concentrations in the elderly. Nutr. Res. 33, 811–816 (2013).

    CAS  PubMed  Google Scholar 

  65. 65.

    Soret, R. et al. Short-chain fatty acids regulate the enteric neurons and control gastrointestinal motility in rats. Gastroenterology 138, 1772–1782 (2010).

    CAS  PubMed  Google Scholar 

  66. 66.

    Gill, P. A., van Zelm, M. C., Muir, J. G. & Gibson, P. R. Review article: short chain fatty acids as potential therapeutic agents in human gastrointestinal and inflammatory disorders. Aliment. Pharmacol. Ther. 48, 15–34 (2018).

    CAS  PubMed  Google Scholar 

  67. 67.

    Smith, P. M. et al. The microbial metabolites, short-chain fatty acids, regulate colonic Treg cell homeostasis. Science 341, 569–573 (2013).

    CAS  PubMed  Google Scholar 

  68. 68.

    Hiippala, K. et al. The potential of gut commensals in reinforcing intestinal barrier function and alleviating inflammation. Nutrients 10, 988 (2018).

    PubMed Central  Google Scholar 

  69. 69.

    Mithieux, G. Metabolic effects of portal vein sensing. Diabetes Obes. Metab. 16, 56–60 (2014).

    CAS  PubMed  Google Scholar 

  70. 70.

    Henningsson, Å., Björck, I. & Nyman, M. Short-chain fatty acid formation at fermentation of indigestible carbohydrates. Näringsforskning 45, 165–168 (2001).

    Google Scholar 

  71. 71.

    Patnode, M. L. et al. Interspecies competition impacts targeted manipulation of human gut bacteria by fiber-derived glycans. Cell 179, 59–73.e13 (2019).

    CAS  PubMed  PubMed Central  Google Scholar 

  72. 72.

    Koh, A., De Vadder, F., Kovatcheva-Datchary, P. & Backhed, F. From dietary fiber to host physiology: short-chain fatty acids as key bacterial metabolites. Cell 165, 1332–1345 (2016).

    CAS  Google Scholar 

  73. 73.

    Reichardt, N. et al. Specific substrate-driven changes in human faecal microbiota composition contrast with functional redundancy in short-chain fatty acid production. ISME J. 12, 610–622 (2018).

    CAS  PubMed  Google Scholar 

  74. 74.

    Titgemeyer, E. C., Bourquin, L. D., Fahey, G. C. Jr & Garleb, K. A. Fermentability of various fiber sources by human fecal bacteria in vitro. Am. J. Clin. Nutr. 53, 1418–1424 (1991).

    CAS  PubMed  Google Scholar 

  75. 75.

    Mortensen, P. B. & Nordgaard-Andersen, I. The dependence of the in vitro fermentation of dietary fibre to short-chain fatty acids on the contents of soluble non-starch polysaccharides. Scand. J. Gastroenterol. 28, 418–422 (1993).

    CAS  PubMed  Google Scholar 

  76. 76.

    Bourquin, L. D., Titgemeyer, E. C., Fahey, G. C. Jr. & Garleb, K. A. Fermentation of dietary fibre by human colonic bacteria: disappearance of, short-chain fatty acid production from, and potential water-holding capacity of, various substrates. Scand. J. Gastroenterol. 28, 249–255 (1993).

    CAS  PubMed  Google Scholar 

  77. 77.

    Pylkas, A. M., Juneja, L. R. & Slavin, J. L. Comparison of different fibers for in vitro production of short chain fatty acids by intestinal microflora. J. Med. Food 8, 113–116 (2005).

    CAS  PubMed  Google Scholar 

  78. 78.

    Lewis, S. J. & Heaton, K. W. Increasing butyrate concentration in the distal colon by accelerating intestinal transit. Gut 41, 245–251 (1997).

    CAS  PubMed  PubMed Central  Google Scholar 

  79. 79.

    Sonnenburg, E. D. & Sonnenburg, J. L. Starving our microbial self: the deleterious consequences of a diet deficient in microbiota-accessible carbohydrates. Cell Metab. 20, 779–786 (2014).

    CAS  PubMed  PubMed Central  Google Scholar 

  80. 80.

    Desai, M. S. et al. A dietary fiber-deprived gut microbiota degrades the colonic mucus barrier and enhances pathogen susceptibility. Cell 167, 1339–1353.e21 (2016).

    CAS  PubMed  PubMed Central  Google Scholar 

  81. 81.

    Brownlee, I. A., Havler, M. E., Dettmar, P. W., Allen, A. & Pearson, J. P. Colonic mucus: secretion and turnover in relation to dietary fibre intake. Proc. Nutr. Soc. 62, 245–249 (2003).

    CAS  PubMed  Google Scholar 

  82. 82.

    Earle, K. A. et al. Quantitative imaging of gut microbiota spatial organization. Cell Host Microbe 18, 478–488 (2015).

    CAS  PubMed  PubMed Central  Google Scholar 

  83. 83.

    Hedemann, M. S., Theil, P. K. & Bach Knudsen, K. E. The thickness of the intestinal mucous layer in the colon of rats fed various sources of non-digestible carbohydrates is positively correlated with the pool of SCFA but negatively correlated with the proportion of butyric acid in digesta. Br. J. Nutr. 102, 117–125 (2009).

    CAS  PubMed  Google Scholar 

  84. 84.

    Riva, A. et al. A fiber-deprived diet disturbs the fine-scale spatial architecture of the murine colon microbiome. Nat. Commun. 10, 4366 (2019).

    PubMed  PubMed Central  Google Scholar 

  85. 85.

    Kerckhoffs, A. P. et al. Lower Bifidobacteria counts in both duodenal mucosa-associated and fecal microbiota in irritable bowel syndrome patients. World J. Gastroenterol. 15, 2887–2892 (2009).

    PubMed  PubMed Central  Google Scholar 

  86. 86.

    Parkes, G. C. et al. Distinct microbial populations exist in the mucosa-associated microbiota of sub-groups of irritable bowel syndrome. Neurogastroenterol. Motil. 24, 31–39 (2012).

    CAS  PubMed  Google Scholar 

  87. 87.

    Morgan, X. C. et al. Dysfunction of the intestinal microbiome in inflammatory bowel disease and treatment. Genome Biol. 13, R79 (2012).

    CAS  PubMed  PubMed Central  Google Scholar 

  88. 88.

    Rajca, S. et al. Alterations in the intestinal microbiome (dysbiosis) as a predictor of relapse after infliximab withdrawal in Crohn’s disease. Inflamm. Bowel Dis. 20, 978–986 (2014).

    PubMed  Google Scholar 

  89. 89.

    Wills, E. S. et al. Fecal microbial composition of ulcerative colitis and Crohn’s disease patients in remission and subsequent exacerbation. PLoS ONE 9, e90981 (2014).

    PubMed  PubMed Central  Google Scholar 

  90. 90.

    Grundy, M. M. L. et al. The impact of oat structure and β-glucan on in vitro lipid digestion. J. Funct. Foods 38, 378–388 (2017).

    CAS  PubMed  PubMed Central  Google Scholar 

  91. 91.

    Edwards, C. H. et al. Manipulation of starch bioaccessibility in wheat endosperm to regulate starch digestion, postprandial glycemia, insulinemia, and gut hormone responses: a randomized controlled trial in healthy ileostomy participants. Am. J. Clin. Nutr. 102, 791–800 (2015).

    CAS  PubMed  PubMed Central  Google Scholar 

  92. 92.

    Stewart, M. L. & Slavin, J. L. Particle size and fraction of wheat bran influence short-chain fatty acid production in vitro. Br. J. Nutr. 102, 1404–1407 (2009).

    CAS  PubMed  Google Scholar 

  93. 93.

    Raghavendra, S. N. et al. Grinding characteristics and hydration properties of coconut residue: a source of dietary fiber. J. Food Eng. 72, 281–286 (2006).

    Google Scholar 

  94. 94.

    Tomlin, J. & Read, N. W. Laxative properties of indigestible plastic particles. BMJ 297, 1175–1176 (1988).

    CAS  PubMed  PubMed Central  Google Scholar 

  95. 95.

    Lewis, S. J. & Heaton, K. W. Stool form scale as a useful guide to intestinal transit time. Scand. J. Gastroenterol. 32, 920–924 (1997).

    CAS  PubMed  Google Scholar 

  96. 96.

    Guillon, F., Auffret, A., Robertson, J. A., Thibault, J. F. & Barry, J. L. Relationships between physical characteristics of sugar-beet fibre and its fermentability by human faecal flora. Carbohydr. Polym. 37, 185–197 (1998).

    CAS  Google Scholar 

  97. 97.

    Harland, B. F. Dietary fibre and mineral bioavailability. Nutr. Res. Rev. 2, 133–147 (1989).

    CAS  PubMed  Google Scholar 

  98. 98.

    Aslam, M. F., Ellis, P. R., Berry, S. E., Latunde-Dada, G. O. & Sharp, P. A. Enhancing mineral bioavailability from cereals: current strategies and future perspectives. Nutr. Bull. 43, 184–188 (2018).

    CAS  PubMed  PubMed Central  Google Scholar 

  99. 99.

    Latunde-Dada, G. O. et al. Micromilling enhances iron bioaccessibility from wholegrain wheat. J. Agric. Food Chem. 62, 11222–11227 (2014).

    CAS  PubMed  Google Scholar 

  100. 100.

    Abrams, S. A., Griffin, I. J. & Hawthorne, K. M. Young adolescents who respond to an inulin-type fructan substantially increase total absorbed calcium and daily calcium accretion to the skeleton. J. Nutr. 137, 2524S–2526S (2007).

    CAS  PubMed  Google Scholar 

  101. 101.

    Whisner, C. M. et al. Galacto-oligosaccharides increase calcium absorption and gut bifidobacteria in young girls: a double-blind cross-over trial. Br. J. Nutr. 110, 1292–1303 (2013).

    CAS  PubMed  Google Scholar 

  102. 102.

    Kasper, H., Rabast, U., Fassl, H. & Fehle, F. The effect of dietary fiber on the postprandial serum vitamin A concentration in man. Am. J. Clin. Nutr. 32, 1847–1849 (1979).

    CAS  PubMed  Google Scholar 

  103. 103.

    Basu, T. K. & Donaldson, D. Intestinal absorption in health and disease: micronutrients. Best Pract. Res. Clin. Gastroenterol. 17, 957–979 (2003).

    CAS  PubMed  Google Scholar 

  104. 104.

    Adams, S., Sello, C., Qin, G.-X., Che, D. & Han, R. Does dietary fiber affect the levels of nutritional components after feed formulation? Fibers 6, 29 (2018).

    Google Scholar 

  105. 105.

    Chan, Y.-M., Aufreiter, S., O’Keefe, S. J. & O’Connor, D. L. Switching to a fibre-rich and low-fat diet increases colonic folate contents among African Americans. Appl. Physiol. Nutr. Metab. 44, 127–132 (2018).

    PubMed  PubMed Central  Google Scholar 

  106. 106.

    Riedl, J., Linseisen, J., Hoffmann, J. & Wolfram, G. Some dietary fibers reduce the absorption of carotenoids in women. J. Nutr. 129, 2170–2176 (1999).

    CAS  PubMed  Google Scholar 

  107. 107.

    Yajima, T. Contractile effect of short-chain fatty acids on the isolated colon of the rat. J. Physiol. 368, 667–678 (1985).

    CAS  PubMed  PubMed Central  Google Scholar 

  108. 108.

    Bueno, L., Praddaude, F., Fioramonti, J. & Ruckebusch, Y. Effect of dietary fiber on gastrointestinal motility and jejunal transit time in dogs. Gastroenterology. 80, 701–707 (1981).

    CAS  PubMed  Google Scholar 

  109. 109.

    de Vries, J., Miller, P. E. & Verbeke, K. Effects of cereal fiber on bowel function: a systematic review of intervention trials. World J. Gastroenterol. 21, 8952–8963 (2015).

    PubMed  PubMed Central  Google Scholar 

  110. 110.

    Brodribb, A. J. & Groves, C. Effect of bran particle size on stool weight. Gut 19, 60–63 (1978).

    CAS  PubMed  PubMed Central  Google Scholar 

  111. 111.

    Burkitt, D. P., Walker, A. R. & Painter, N. S. Effect of dietary fibre on stools and the transit-times, and its role in the causation of disease. Lancet 2, 1408–1412 (1972).

    CAS  PubMed  Google Scholar 

  112. 112.

    Harvey, R. F., Pomare, E. W. & Heaton, K. W. Effects of increased dietary fibre on intestinal transit. Lancet 1, 1278–1280 (1973).

    CAS  PubMed  Google Scholar 

  113. 113.

    Baird, I. M. et al. The effects of two dietary fiber supplements on gastrointestinal transit, stool weight and frequency, and bacterial flora, and fecal bile acids in normal subjects. Metabolism 26, 117–128 (1977).

    CAS  PubMed  Google Scholar 

  114. 114.

    Gear, J. S., Brodribb, A. J., Ware, A. & Mann, J. I. Fibre and bowel transit times. Br. J. Nutr. 45, 77–82 (1981).

    CAS  PubMed  Google Scholar 

  115. 115.

    Stevens, J., VanSoest, P. J., Robertson, J. B. & Levitsky, D. A. Comparison of the effects of psyllium and wheat bran on gastrointestinal transit time and stool characteristics. J. Am. Diet. Assoc. 88, 323–326 (1988).

    CAS  PubMed  Google Scholar 

  116. 116.

    Muller-Lissner, S. A. Effect of wheat bran on weight of stool and gastrointestinal transit time: a meta analysis. Br. Med. J. 296, 615–617 (1988).

    CAS  Google Scholar 

  117. 117.

    Rao, S. S. et al. Investigation of colonic and whole-gut transit with wireless motility capsule and radiopaque markers in constipation. Clin. Gastroenterol. Hepatol. 7, 537–544 (2009).

    PubMed  Google Scholar 

  118. 118.

    Maqbool, S., Parkman, H. P. & Friedenberg, F. K. Wireless capsule motility: comparison of the SmartPill GI monitoring system with scintigraphy for measuring whole gut transit. Dig. Dis. Sci. 54, 2167–2174 (2009).

    PubMed  Google Scholar 

  119. 119.

    Timm, D. et al. The use of a wireless motility device (SmartPill(R)) for the measurement of gastrointestinal transit time after a dietary fibre intervention. Br. J. Nutr. 105, 1337–1342 (2011).

    CAS  PubMed  Google Scholar 

  120. 120.

    Spiller, G. A., Shipley, E. A., Chernoff, M. C. & Cooper, W. C. Bulk laxative efficacy of a psyllium seed hydrocolloid and of a mixture of cellulose and pectin. J. Clin. Pharmacol. 19, 313–320 (1979).

    CAS  PubMed  Google Scholar 

  121. 121.

    Bouhnik, Y. et al. Short-chain fructo-oligosaccharide administration dose-dependently increases fecal bifidobacteria in healthy humans. J. Nutr. 129, 113–116 (1999).

    CAS  PubMed  Google Scholar 

  122. 122.

    Vuksan, V. et al. Using cereal to increase dietary fiber intake to the recommended level and the effect of fiber on bowel function in healthy persons consuming North American diets. Am. J. Clin. Nutr. 88, 1256–1262 (2008).

    CAS  PubMed  Google Scholar 

  123. 123.

    Suares, N. C. & Ford, A. C. Systematic review: the effects of fibre in the management of chronic idiopathic constipation. Aliment. Pharmacol. Ther. 33, 895–901 (2011).

    CAS  PubMed  Google Scholar 

  124. 124.

    Christodoulides, S. et al. Systematic review with meta-analysis: effect of fibre supplementation on chronic idiopathic constipation in adults. Aliment. Pharmacol. Ther. 44, 103–116 (2016).

    CAS  PubMed  Google Scholar 

  125. 125.

    Kato, M. et al. Cell-free formation of RNA granules: low complexity sequence domains form dynamic fibers within hydrogels. Cell 149, 753–767 (2012).

    CAS  PubMed  PubMed Central  Google Scholar 

  126. 126.

    Bliss, D. Z. et al. Dietary fiber supplementation for fecal incontinence: a randomized clinical trial. Res. Nurs. Health 37, 367–378 (2014).

    PubMed  PubMed Central  Google Scholar 

  127. 127.

    Washington, N., Harris, M., Mussellwhite, A. & Spiller, R. C. Moderation of lactulose-induced diarrhea by psyllium: effects on motility and fermentation. Am. J. Clin. Nutr. 67, 317–321 (1998).

    CAS  PubMed  Google Scholar 

  128. 128.

    Tomlin, J. & Read, N. W. The effect of inert plastic particles on colonic function in human volunteers. Gastroenterology 94, A463–A463 (1988).

    Google Scholar 

  129. 129.

    Hongisto, S. M., Paajanen, L., Saxelin, M. & Korpela, R. A combination of fibre-rich rye bread and yoghurt containing Lactobacillus GG improves bowel function in women with self-reported constipation. Eur. J. Clin. Nutr. 60, 319–324 (2006).

    CAS  PubMed  Google Scholar 

  130. 130.

    Holma, R., Hongisto, S. M., Saxelin, M. & Korpela, R. Constipation is relieved more by rye bread than wheat bread or laxatives without increased adverse gastrointestinal effects. J. Nutr. 140, 534–541 (2010).

    CAS  PubMed  Google Scholar 

  131. 131.

    de Vries, J., Birkett, A., Hulshof, T., Verbeke, K. & Gibes, K. Effects of cereal, fruit and vegetable fibers on human fecal weight and transit time: a comprehensive review of intervention trials. Nutrients 8, 130 (2016).

    PubMed  PubMed Central  Google Scholar 

  132. 132.

    Gibson, G. R. et al. Expert consensus document: The International Scientific Association for Probiotics and Prebiotics (ISAPP) consensus statement on the definition and scope of prebiotics. Nat. Rev. Gastroenterol. Hepatol. 14, 491–502 (2017).

    PubMed  Google Scholar 

  133. 133.

    So, D. et al. Dietary fiber intervention on gut microbiota composition in healthy adults: a systematic review and meta-analysis. Am. J. Clin. Nutr. 107, 965–983 (2018).

    PubMed  Google Scholar 

  134. 134.

    Macfarlane, G. T., Steed, H. & Macfarlane, S. Bacterial metabolism and health-related effects of galacto-oligosaccharides and other prebiotics. J. Appl. Microbiol. 104, 305–344 (2008).

    CAS  PubMed  Google Scholar 

  135. 135.

    Ramirez-Farias, C. et al. Effect of inulin on the human gut microbiota: stimulation of Bifidobacterium adolescentis and Faecalibacterium prausnitzii. Br. J. Nutr. 101, 541–550 (2009).

    CAS  PubMed  Google Scholar 

  136. 136.

    Sonnenburg, E. D. et al. Specificity of polysaccharide use in intestinal bacteroides species determines diet-induced microbiota alterations. Cell 141, 1241–1252 (2010).

    CAS  PubMed  PubMed Central  Google Scholar 

  137. 137.

    Wilson, B. & Whelan, K. Prebiotic inulin-type fructans and galacto-oligosaccharides: definition, specificity, function, and application in gastrointestinal disorders. J. Gastroenterol. Hepatol. 32, 64–68 (2017).

    CAS  PubMed  Google Scholar 

  138. 138.

    Gibson, G. R., Beatty, E. R., Wang, X. & Cummings, J. H. Selective stimulation of bifidobacteria in the human colon by oligofructose and inulin. Gastroenterology. 108, 975–982 (1995).

    CAS  PubMed  Google Scholar 

  139. 139.

    Davis, L. M., Martinez, I., Walter, J. & Hutkins, R. A dose dependent impact of prebiotic galactooligosaccharides on the intestinal microbiota of healthy adults. Int. J. Food Microbiol. 144, 285–292 (2010).

    CAS  PubMed  Google Scholar 

  140. 140.

    Tap, J. et al. Gut microbiota richness promotes its stability upon increased dietary fibre intake in healthy adults. Env. Microbiol. 17, 4954–4964 (2015).

    CAS  Google Scholar 

  141. 141.

    de Preter, V. et al. Baseline microbiota activity and initial bifidobacteria counts influence responses to prebiotic dosing in healthy subjects. Aliment. Pharmacol. Ther. 27, 504–513 (2008).

    PubMed  Google Scholar 

  142. 142.

    Kolida, S., Meyer, D. & Gibson, G. R. A double-blind placebo-controlled study to establish the bifidogenic dose of inulin in healthy humans. Eur. J. Clin. Nutr. 61, 1189–1195 (2007).

    CAS  PubMed  Google Scholar 

  143. 143.

    Bouhnik, Y. et al. Prolonged administration of low-dose inulin stimulates the growth of bifidobacteria in humans. Nutr. Res. 27, 187–193 (2007).

    CAS  Google Scholar 

  144. 144.

    Bouhnik, Y. et al. Four-week short chain fructo-oligosaccharides ingestion leads to increasing fecal bifidobacteria and cholesterol excretion in healthy elderly volunteers. Nutr. J. 6, 42–42 (2007).

    PubMed  PubMed Central  Google Scholar 

  145. 145.

    Healey, G. et al. Habitual dietary fibre intake influences gut microbiota response to an inulin-type fructan prebiotic: a randomised, double-blind, placebo-controlled, cross-over, human intervention study. Br. J. Nutr. 119, 176–189 (2018).

    CAS  PubMed  Google Scholar 

  146. 146.

    Lacy, B. E. et al. Bowel disorders. Gastroenterology 150, 1393–1407.e5 (2016).

    Google Scholar 

  147. 147.

    Palsson, O. S. et al. Rome IV diagnostic questionnaires and tables for investigators and clinicians. Gastroenterology 150, 1481–1491 (2016).

    Google Scholar 

  148. 148.

    Quigley, E. M. M. et al. Irritable bowel syndrome: a global perspective. World Gastroenterology Organisation Global Guidelines (2015).

  149. 149.

    Rao, S. S., Yu, S. & Fedewa, A. Systematic review: dietary fibre and FODMAP-restricted diet in the management of constipation and irritable bowel syndrome. Aliment. Pharmacol. Ther. 41, 1256–1270 (2015).

    CAS  PubMed  Google Scholar 

  150. 150.

    Nagarajan, N. et al. The role of fiber supplementation in the treatment of irritable bowel syndrome: a systematic review and meta-analysis. Eur. J. Gastroenterol. Hepatol. 27, 1002–1010 (2015).

    CAS  PubMed  Google Scholar 

  151. 151.

    Ford, A. C. et al. Effect of fibre, antispasmodics, and peppermint oil in the treatment of irritable bowel syndrome: systematic review and meta-analysis. BMJ 337, a2313 (2008).

    PubMed  PubMed Central  Google Scholar 

  152. 152.

    Moayyedi, P. et al. The effect of fiber supplementation on irritable bowel syndrome: a systematic review and meta-analysis. Am. J. Gastroenterol. 109, 1367–1374 (2014).

    CAS  PubMed  Google Scholar 

  153. 153.

    Major, G. et al. Colon hypersensitivity to distension, rather than excessive gas production, produces carbohydrate-related symptoms in individuals with irritable bowel syndrome. Gastroenterology 152, 124–133.e2 (2017).

    PubMed  Google Scholar 

  154. 154.

    Hunter, J. O., Tuffnell, Q. & Lee, A. J. Controlled trial of oligofructose in the management of irritable bowel syndrome. J. Nutr. 129, 1451S–1453S (1999).

    CAS  PubMed  Google Scholar 

  155. 155.

    Olesen, M. & Gudmand-Hoyer, E. Efficacy, safety, and tolerability of fructooligosaccharides in the treatment of irritable bowel syndrome. Am. J. Clin. Nutr. 72, 1570–1575 (2000).

    CAS  PubMed  Google Scholar 

  156. 156.

    Paineau, D. et al. The effects of regular consumption of short-chain fructo-oligosaccharides on digestive comfort of subjects with minor functional bowel disorders. Br. J. Nutr. 99, 311–318 (2008).

    CAS  PubMed  Google Scholar 

  157. 157.

    Silk, D. B., Davis, A., Vulevic, J., Tzortzis, G. & Gibson, G. R. Clinical trial: the effects of a trans-galactooligosaccharide prebiotic on faecal microbiota and symptoms in irritable bowel syndrome. Aliment. Pharmacol. Ther. 29, 508–518 (2009).

    CAS  PubMed  Google Scholar 

  158. 158.

    Wilson, B., Rossi, M., Dimidi, E. & Whelan, K. Prebiotics in irritable bowel syndrome and other functional bowel disorders in adults: a systematic review and meta-analysis of randomized controlled trials. Am. J. Clin. Nutr. 109, 1098–1111 (2019).

    PubMed  Google Scholar 

  159. 159.

    Ford, A. C. et al. Efficacy of prebiotics, probiotics, and synbiotics in irritable bowel syndrome and chronic idiopathic constipation: systematic review and meta-analysis. Am. J. Gastroenterol. 109, 1547–1561 (2014).

    PubMed  Google Scholar 

  160. 160.

    Hotchkiss, A. T., Olano-Martin, E., Grace, W. E., Gibson, G. R. & Rastall, R. A. Pectic oligosaccharides as prebiotics. Oligosacch. Food Agric. 849, 54–62 (2003).

    CAS  Google Scholar 

  161. 161.

    Russo, L. et al. Partially hydrolyzed guar gum in the treatment of irritable bowel syndrome with constipation: effects of gender, age, and body mass index. Saudi J. Gastroenterol. 21, 104–110 (2015).

    PubMed  PubMed Central  Google Scholar 

  162. 162.

    Abraham, C. & Medzhitov, R. Interactions between the host innate immune system and microbes in inflammatory bowel disease. Gastroenterology 140, 1729–1737 (2011).

    CAS  PubMed  PubMed Central  Google Scholar 

  163. 163.

    Cao, Y., Shen, J. & Ran, Z. H. Association between Faecalibacterium prausnitzii reduction and inflammatory bowel disease: a meta-analysis and systematic review of the literature. Gastroenterol. Res. Pract. 2014, 872725 (2014).

    PubMed  PubMed Central  Google Scholar 

  164. 164.

    Ng, S. C. et al. Worldwide incidence and prevalence of inflammatory bowel disease in the 21st century: a systematic review of population-based studies. Lancet 390, 2769–2778 (2018).

    PubMed  Google Scholar 

  165. 165.

    Wedlake, L., Slack, N., Andreyev, H. J. & Whelan, K. Fiber in the treatment and maintenance of inflammatory bowel disease: a systematic review of randomized controlled trials. Inflamm. Bowel Dis. 20, 576–586 (2014).

    PubMed  Google Scholar 

  166. 166.

    Cavaglieri, C. R. et al. Differential effects of short-chain fatty acids on proliferation and production of pro- and anti-inflammatory cytokines by cultured lymphocytes. Life Sci. 73, 1683–1690 (2003).

    CAS  PubMed  Google Scholar 

  167. 167.

    Asarat, M., Apostolopoulos, V., Vasiljevic, T. & Donkor, O. Short-chain fatty acids regulate cytokines and Th17/Treg cells in human peripheral blood mononuclear cells in vitro. Immunol. Invest. 45, 205–222 (2016).

    CAS  PubMed  Google Scholar 

  168. 168.

    Lindsay, J. O. et al. Clinical, microbiological, and immunological effects of fructo-oligosaccharide in patients with Crohn’s disease. Gut 55, 348–355 (2006).

    CAS  PubMed  PubMed Central  Google Scholar 

  169. 169.

    De Preter, V. et al. Metabolic profiling of the impact of oligofructose-enriched inulin in Crohn’s disease patients: a double-blinded randomized controlled trial. Clin. Transl. Gastroenterol. 4, e30 (2013).

    PubMed  PubMed Central  Google Scholar 

  170. 170.

    James, S. L. et al. Abnormal fibre usage in UC in remission. Gut 64, 562–570 (2015).

    CAS  PubMed  Google Scholar 

  171. 171.

    Treem, W. R., Ahsan, N., Shoup, M. & Hyams, J. S. Fecal short-chain fatty acids in children with inflammatory bowel disease. J. Pediatr. Gastroenterol. Nutr. 18, 159–164 (1994).

    CAS  PubMed  Google Scholar 

  172. 172.

    Takaishi, H. et al. Imbalance in intestinal microflora constitution could be involved in the pathogenesis of inflammatory bowel disease. Int. J. Med. Microbiol. 298, 463–472 (2008).

    CAS  PubMed  Google Scholar 

  173. 173.

    Ananthakrishnan, A. N. et al. A prospective study of long-term intake of dietary fiber and risk of Crohn’s disease and ulcerative colitis. Gastroenterology 145, 970–977 (2013).

    CAS  PubMed  PubMed Central  Google Scholar 

  174. 174.

    Li, F., Liu, X., Wang, W. & Zhang, D. Consumption of vegetables and fruit and the risk of inflammatory bowel disease: a meta-analysis. Eur. J. Gastroenterol. Hepatol. 27, 623–630 (2015).

    PubMed  Google Scholar 

  175. 175.

    Andersen, V. et al. Fibre intake and the development of inflammatory bowel disease: a European prospective multi-centre cohort study (EPIC-IBD). J. Crohns Colitis 12, 129–136 (2018).

    PubMed  Google Scholar 

  176. 176.

    Brotherton, C. S., Martin, C. A., Long, M. D., Kappelman, M. D. & Sandler, R. S. Avoidance of fiber is associated with greater risk of Crohn’s disease flare in a 6-month period. Clin. Gastroenterol. Hepatol. 14, 1130–1136 (2016).

    PubMed  Google Scholar 

  177. 177.

    Thaha, M. A. & Carrington, E. Diverticular disease. BMJ Best Practice (2019).

  178. 178.

    Rezapour, M., Ali, S. & Stollman, N. Diverticular disease: an update on pathogenesis and management. Gut Liver 12, 125–132 (2018).

    CAS  PubMed  Google Scholar 

  179. 179.

    Lanas, A., Abad-Baroja, D. & Lanas-Gimeno, A. Progress and challenges in the management of diverticular disease: which treatment? Therap. Adv. Gastroenterol. 11, 1756284818789055 (2018).

    PubMed  PubMed Central  Google Scholar 

  180. 180.

    Onur, M. R., Akpinar, E., Karaosmanoglu, A. D., Isayev, C. & Karcaaltincaba, M. Diverticulitis: a comprehensive review with usual and unusual complications. Insights Imaging 8, 19–27 (2017).

    PubMed  Google Scholar 

  181. 181.

    Strate, L. L. et al. Western dietary pattern increases, and prudent dietary pattern decreases, risk of incident diverticulitis in a prospective cohort study. Gastroenterology. 152, 1023–1030.e2 (2017).

    PubMed  PubMed Central  Google Scholar 

  182. 182.

    Crowe, F. L. et al. Source of dietary fibre and diverticular disease incidence: a prospective study of UK women. Gut 63, 1450–1456 (2014).

    PubMed  PubMed Central  Google Scholar 

  183. 183.

    Peery, A. F. et al. A high-fiber diet does not protect against asymptomatic diverticulosis. Gastroenterology 142, 266–272.e1 (2012).

    PubMed  Google Scholar 

  184. 184.

    Aune, D., Sen, A., Norat, T. & Riboli, E. Dietary fibre intake and the risk of diverticular disease: a systematic review and meta-analysis of prospective studies. Eur. J. Nutr. 59, 421–432 (2020).

    PubMed  Google Scholar 

  185. 185.

    Wick, J. Y. Diverticular disease: eat your fiber! Consult. Pharm. 27, 613–618 (2012).

    PubMed  Google Scholar 

  186. 186.

    Dahl, C. et al. Evidence for dietary fibre modification in the recovery and prevention of reoccurrence of acute, uncomplicated diverticulitis: a systematic literature review. Nutrients. 10, 137 (2018).

    PubMed Central  Google Scholar 

  187. 187.

    Unlu, C., Daniels, L., Vrouenraets, B. C. & Boermeester, M. A. A systematic review of high-fibre dietary therapy in diverticular disease. Int. J. Colorectal Dis. 27, 419–427 (2012).

    PubMed  Google Scholar 

  188. 188.

    Brodribb, A. J. Treatment of symptomatic diverticular disease with a high-fibre diet. Lancet 1, 664–666 (1977).

    CAS  PubMed  Google Scholar 

  189. 189.

    Ornstein, M. H. et al. Are fibre supplements really necessary in diverticular disease of the colon? A controlled clinical trial. Br. Med. J. 282, 1353–1356 (1981).

    CAS  Google Scholar 

  190. 190.

    Hodgson, W. J. The placebo effect. Is it important in diverticular disease? Am. J. Gastroenterol. 67, 157–162 (1977).

    CAS  PubMed  Google Scholar 

  191. 191.

    Eberhardt, F. et al. Role of dietary fibre in older adults with asymptomatic (AS) or symptomatic uncomplicated diverticular disease (SUDD): systematic review and meta-analysis. Maturitas 130, 57–67 (2019).

    CAS  PubMed  Google Scholar 

  192. 192.

    Dukas, L., Willett, W. C. & Giovannucci, E. L. Association between physical activity, fiber intake, and other lifestyle variables and constipation in a study of women. Am. J. Gastroenterol. 98, 1790–1796 (2003).

    PubMed  Google Scholar 

  193. 193.

    Dimidi, E., Cox, C., Grant, R., Scott, S. M. & Whelan, K. Perceptions of constipation among the general public and people with constipation differ strikingly from those of general and specialist doctors and the Rome IV criteria. Am. J. Gastroenterol. 114, 1116–1129 (2019).

    PubMed  Google Scholar 

  194. 194.

    Sanjoaquin, M. A., Appleby, P. N., Spencer, E. A. & Key, T. J. Nutrition and lifestyle in relation to bowel movement frequency: a cross-sectional study of 20630 men and women in EPIC-Oxford. Public Health Nutr. 7, 77–83 (2004).

    PubMed  Google Scholar 

  195. 195.

    Alrefaai, L., Cade, J. E. & Burley, V. J. Dietary fibre intake and constipation in the UK Women’s Cohort Study. Proc. Nutr. Soc. 72, E287–E287 (2013).

    Google Scholar 

  196. 196.

    Lewis, S. J. & Heaton, K. W. Roughage revisited: the effect on intestinal function of inert plastic particles of different sizes and shape. Dig. Dis. Sci. 44, 744–748 (1999).

    CAS  PubMed  Google Scholar 

  197. 197.

    Wrick, K. L. et al. The influence of dietary fiber source on human intestinal transit and stool output. J. Nutr. 113, 1464–1479 (1983).

    CAS  PubMed  Google Scholar 

  198. 198.

    McRorie, J. W. Jr. & McKeown, N. M. Understanding the physics of functional fibers in the gastrointestinal tract: an evidence-based approach to resolving enduring misconceptions about insoluble and soluble fiber. J. Acad. Nutr. Diet. 117, 251–264 (2017).

    PubMed  Google Scholar 

  199. 199.

    O’Keefe, S. J. The association between dietary fibre deficiency and high-income lifestyle-associated diseases: Burkitt’s hypothesis revisited. Lancet Gastroenterol. Hepatol. 4, 984–996 (2019).

    PubMed  PubMed Central  Google Scholar 

  200. 200.

    Muir, J. G. et al. Combining wheat bran with resistant starch has more beneficial effects on fecal indexes than does wheat bran alone. Am. J. Clin. Nutr. 79, 1020–1028 (2004).

    CAS  PubMed  Google Scholar 

  201. 201.

    Govers, M. J., Gannon, N. J., Dunshea, F. R., Gibson, P. R. & Muir, J. G. Wheat bran affects the site of fermentation of resistant starch and luminal indexes related to colon cancer risk: a study in pigs. Gut 45, 840–847 (1999).

    CAS  PubMed  PubMed Central  Google Scholar 

  202. 202.

    Tuncil, Y. E. et al. Delayed utilization of some fast-fermenting soluble dietary fibers by human gut microbiota when presented in a mixture. J. Funct. Foods 32, 347–357 (2017).

    CAS  Google Scholar 

  203. 203.

    Harmayani, E. et al. Healthy food traditions of Asia: exploratory case studies from Indonesia, Thailand, Malaysia, and Nepal. J. Ethnic Foods 6, 1 (2019).

    Google Scholar 

  204. 204.

    McRorie, J. W. Jr. Evidence-based approach to fiber supplements and clinically meaningful health benefits, part 2: what to look for and how to recommend an effective fiber therapy. Nutr. Today 50, 90–97 (2015).

    PubMed  PubMed Central  Google Scholar 

  205. 205.

    Zielinski, G., DeVries, J. W., Craig, S. A. & Bridges, A. R. Dietary fiber methods in Codex Alimentarius: current status and ongoing discussions. Cereal Food World 58, 148–152 (2013).

    Google Scholar 

  206. 206.

    Food and Agriculture Organization/World Health Organization Codex Alimentarius Commission. Codex Alimentarius: Guidelines on Nutrition Labelling CAC/GL 2-1985. (FAO, 2010).

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The authors acknowledge research funding from the Medical Research Council investigating the effect of fibre on the gut (MR/N029097/1).

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All authors researched data for the article, contributed to discussion and reviewed/edited the manuscript before submission. S.K.G. and K.W. wrote the article.

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Correspondence to Kevin Whelan.

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The authors have received research grants related to dietary fibre from government agencies including the Medical Research Council and commercial funders including Clasado Biosciences, Danone, Nestec, Almond Board of California and the International Nut and Dried Fruit Council.

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Gill, S.K., Rossi, M., Bajka, B. et al. Dietary fibre in gastrointestinal health and disease. Nat Rev Gastroenterol Hepatol 18, 101–116 (2021).

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