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dietary fiber

Fibrous material (general polysaccharide) passing through the digestive system without intestinal obsorption. Indications: - soluble fiber is used for prevention & treatment of dyslipidemia [3] - insoluble fiber is used for prevention & treatment of constipation - soluble fiber may be of benefit in chronic constipation - data for insoluble fiber are conflicting [9] - wheat bran effective in the short term [11] - both types of fiber may be useful for weight reduction - both soluble (fruit) & insoluble fiber (wheat bran, brown rice ...) lowers cardiovascular risk (RR= 0.9) [4] - soluble (viscous) fiber lowers LDL cholesterol & estimated 10-year cardiovascular risk [2,15,16] - dietary fiber lowers risk of: [6] - coronary artery disease - ischemic stroke - hypertension - diabetes mellitus type 2 - obesity - gastrointestinal disorders - gastroesophageal reflux disease, - duodenal ulcer - diverticulitis - does not protect against asymptomatic diverticulosis [10] - constipation - hemorrhoids - colorectal cancer [12] - soluble fiber improves glycemia & insulin sensitivity [6] - dietary fiber reduces mortality from - cardiovascular disease - cereal fiber intake is associated with lower levels ofinflammatory markers & lower risk of cardiovascular disease [17] - inflammation mediates ~1/6 of the association between cereal fiber intake & cardiovascular disease [17] - infection - respiratory disease [7] - colorectal cancer [12] - diabetes mellitus type 2 [12] - dietary fiber may lower risk for lung cancer (RR=0.8) [14] - 15-30 g of fiber daily confers greatest benefits [12] Adverse effects: - no evidence that fiber, soluble or insoluble, interferes with absorption of vitamins or minerals Mechanism of action: - insoluble fiber asorbs water & increases bulk of the stool thus stimulating peristalsis - soluble fiber lowers serum total cholesterol & LDL cholesterol by 4-8% - the ileum contains enteroendocrine L-cells, which release hormones that suppress appetite, including glucagon-like peptide-1 (GLP-1) & the peptide tyrosine-tyrosine (PYY), in response to food intake [18] Comparative biology: - mice fed high-fiber diet (mostly soluble fiber) - higher levels of short-chain fatty acids in gut & in blood - Clostridium species in gut largely responsible - decreased airway levels of eosinophils, IL-4 , IL-5, & total IgE, & less mucus production & airway hyperreactivity in response to dust mite allergen exposure [5]

Specific

bran cellulose (Calcibind) rice bran wheat dextran; wheat bran; Miller's bran (Benefiber)

General

dietary supplement (nutraceutical, medicinal food)

References

  1. Stedman's Medical Dictionary 27th ed, Williams & Wilkins, Baltimore, 1999
  2. Geriatric Review Syllabus, 7th edition Parada JT et al (eds) American Geriatrics Society, 2010 - Geriatric Review Syllabus, 8th edition (GRS8) Durso SC and Sullivan GN (eds) American Geriatrics Society, 2013 - Geriatric Review Syllabus, 11th edition (GRS11) Harper GM, Lyons WL, Potter JF (eds) American Geriatrics Society, 2022
  3. Grooms KN et al Dietary Fiber Intake and Cardiometabolic Risks among US Adults, NHANES 1999-2010. American Journal of Medicine. Oct 16, 2013 PMID: 24135514 http://www.amjmed.com/article/S0002-9343(13)00631-1/abstract
  4. Threapleton DE et al Dietary fibre intake and risk of cardiovascular disease: systematic review and meta-analysis. BMJ 2013;347:f6879 PMID: 24355537 http://www.bmj.com/content/347/bmj.f6879 - Baron RB Eat more fibre. BMJ 2013;347:f7401 PMID: 24355540 http://www.bmj.com/content/347/bmj.f7401
  5. Trompette A et al. Gut microbiota metabolism of dietary fiber influences allergic airway disease and hematopoiesis. Nat Med 2014 Feb; 20:159 PMID: 24390308 - Huffnagle GB. Increase in dietary fiber dampens allergic responses in the lung. Nat Med 2014 Feb 6; 20:120 PMID: 24504401
  6. Anderson JW, Baird P, Davis RH Jr et al Health benefits of dietary fiber. Nutr Rev. 2009 Apr;67(4):188-205 PMID: 19335713
  7. Park Y, Subar AF, Hollenbeck A, Schatzkin A. Dietary fiber intake and mortality in the NIH-AARP diet and health study. Arch Intern Med. 2011 Jun 27;171(12):1061-8. PMID: 21321288
  8. Wolfram T, Ismail-Beigi F. Efficacy of high-fiber diets in the management of type 2 diabetes mellitus. Endocr Pract. 2011 Jan-Feb;17(1):132-42. Review. PMID: 20713332
  9. Suares NC, Ford AC. Systematic review: the effects of fibre in the management of chronic idiopathic constipation. Aliment Pharmacol Ther. 2011 Apr;33(8):895-901. PMID: 21332763
  10. Peery AF, Barrett PR, Park D A high-fiber diet does not protect against asymptomatic diverticulosis. Gastroenterology. 2012 Feb;142(2):266-72.e1. PMID: 22062360
  11. Lawton CL, Walton J, Hoyland A et al Short term (14 days) consumption of insoluble wheat bran fibre-containing breakfast cereals improves subjective digestive feelings, general wellbeing and bowel function in a dose dependent manner. Nutrients. 2013 Apr 22;5(4):1436-55. PMID: 23609776
  12. Reynolds A, Mann J, Cummings J et al Carbohydrate quality and human health: a series of systematic reviews and meta-analyses. Lancet. Jan 10, 2019 PMID: 30638909 https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(18)31809-9/fulltext
  13. Rubin R High-Fiber Diet Might Protect Against Range of Conditions. JAMA. Published online April 17, 2019 PMID: 30994909 https://jamanetwork.com/journals/jama/fullarticle/2731599
  14. Ingram I Gobbling Up Yogurt, Fiber Tied to Lower Lung Cancer Risk. Potential synergistic effect with greater consumption of both. MedPage Today. Oct 24, 2019 https://www.medpagetoday.com/hematologyoncology/lungcancer/82933 - Yang JJ, Yu D, Xiang YB et al Association of Dietary Fiber and Yogurt Consumption With Lung Cancer Risk. A Pooled Analysis. JAMA Oncol. Published online October 24, 2019 PMID: 31647500 https://jamanetwork.com/journals/jamaoncology/article-abstract/2753175
  15. Salvado J, Jenkins DJA, Kendall CWC, Sievenpiper JL. Portfolio Dietary Pattern and Cardiovascular Disease: A Systematic Review and Meta-analysis of Controlled Trials. Prog Cardiovasc Dis. 2018 May-Jun;61(1):43-53 PMID: 29807048 Review
  16. Surampudi P, Enkhmaa B, Anuurad E, Berglund L. Lipid Lowering with Soluble Dietary Fiber. Curr Atheroscler Rep. 2016 Dec;18(12):75. PMID: 27807734 Review.
  17. Shivakoti R, Biggs ML,Djouss L et al Intake and Sources of Dietary Fiber, Inflammation, and Cardiovascular Disease in Older US Adults. JAMA Netw Open. 2022;5(3):e225012 PMID: 35357453 Free article https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2790576
  18. Dagbasi A, Byrne C, Blunt D et al Diet shapes the metabolite profile in the intact human ileum, which affects PYY release. Sci Transl Med. 2024 Jun 19;16(752):eadm8132. PMID: 38896603 Clinical Trial. https://www.science.org/doi/10.1126/scitranslmed.adm8132