FODMAPs or fermentable oligosaccharides, disaccharides, monosaccharides, and polyols[1] are short-chain carbohydrates that are poorly absorbed in the small intestine and ferment in the colon. They include short-chain oligosaccharide polymers of fructose (fructans) and galactooligosaccharides (GOS, stachyose, raffinose), disaccharides (lactose), monosaccharides (fructose), and sugar alcohols (polyols), such as sorbitol, mannitol, xylitol, and maltitol.[1][2] Most FODMAPs are naturally present in food and the human diet, but the polyols may be added artificially in commercially prepared foods and beverages.

FODMAPs may cause digestive discomfort in some people. The reasons are hypersensitivity to luminal distension and/or a proclivity to excess water retention and gas production and accumulation, but they do not cause intestinal inflammation. Naturally occurring FODMAPs may help avert digestive discomfort for some people because they produce beneficial alterations in the gut flora.[3][4][5][6] They are not the cause of these disorders,[7] but a low-FODMAP diet, restricting FODMAPs, might help to improve digestive symptoms in adults with irritable bowel syndrome (IBS) and other functional gastrointestinal disorders (FGID).[7][8][9][10][11] Avoiding all FODMAPs long-term may have a detrimental impact on the gut microbiota and metabolome.[2][9][11][12]

FODMAPs, especially fructans, are present in small amounts in gluten-containing grains and have been identified as a possible cause of symptoms in people with non-celiac gluten sensitivity.[13][14][15][16][3] They are only minor sources of FODMAPs when eaten in the usual standard quantities in the daily diet.[13] As of 2019, reviews conclude that although FODMAPs present in wheat and related grains may play a role in non-celiac gluten sensitivity, they only explain certain gastrointestinal symptoms, such as bloating, but not the extra-digestive symptoms that people with non-celiac gluten sensitivity may develop, such as neurological disorders, fibromyalgia, psychological disturbances, and dermatitis.[3][17][13] Consuming a low FODMAP diet without a previous medical evaluation could cause health risks because it can ameliorate and mask digestive symptoms of celiac disease, delaying or avoiding its correct diagnosis and therapy.[18]

Absorption edit

Some FODMAPs, such as fructose, are readily absorbed in the small intestine of humans via GLUT receptors.[19] Absorption thus depends on the appropriate expression and delivery of these receptors in the intestinal enterocyte to both the apical surface, contacting the lumen of the intestine (e.g., GLUT5), and to the basal membrane, contacting the blood (e.g., GLUT2).[19] Improper absorption of these FODMAPS in the small intestine leaves them available for absorption by gut flora. The resultant metabolism by the gut flora leads to the production of gas and potentially results in bloating and flatulence.[7]

Although FODMAPs can cause certain digestive discomfort in some people, not only do they not cause intestinal inflammation, but they help prevent it because they produce beneficial alterations in the intestinal flora that contribute to maintaining good colon health.[4][5][6]

FODMAPs are not the cause of irritable bowel syndrome or other functional gastrointestinal disorders, but rather a person develops symptoms when the underlying bowel response is exaggerated or abnormal.[7]

Fructose malabsorption and lactose intolerance may produce IBS symptoms through the same mechanism, but unlike other FODMAPs, poor absorption of fructose is found in only a minority of people. Lactose intolerance is found in most adults, except for specific geographic populations, notably those of European descent.[20] Many who benefit from a low FODMAP diet need not restrict fructose or lactose. It is possible to identify these two conditions with hydrogen and methane breath testing, thus eliminating the necessity for dietary compliance.[7]

Sources in the diet edit

The significance of sources of FODMAPs varies through differences in dietary groups such as geography, ethnicity, and other factors.[7] Commonly used FODMAPs comprise the following:[21]

  • oligosaccharides, including fructans and galactooligosaccharides
  • disaccharides, including lactose
  • monosaccharides, including fructose
  • polyols, including sorbitol, xylitol, and mannitol

Fructans, galactans, and polyols edit

Sources of fructans edit

Sources of fructans include wheat, rye, barley, onion, garlic, Jerusalem and globe artichoke, beetroot, dandelion leaves, the white part of leeks, the white part of spring onion, brussels sprouts, savoy cabbage, and prebiotics such as fructooligosaccharides (FOS), oligofructose and inulin.[22][failed verification][7][23] Asparagus, fennel, red cabbage, and radicchio contain moderate amounts but may be eaten if the advised portion size is observed.[22][failed verification]

Sources of galactans edit

Pulses and beans are the main dietary sources (although green beans, canned lentils, sprouted mung beans, tofu (not silken), and tempeh contain comparatively low amounts).[22][failed verification][23] Supplements of the enzyme alpha-galactosidase may reduce symptoms,[24] assuming the enzyme product does not contain other FODMAPs, such as polyol artificial sweeteners.[citation needed]

Sources of polyols edit

Polyols are found naturally in mushrooms, some fruit (particularly stone fruits), including apples, apricots, avocados, blackberries, cherries, lychees, nectarines, peaches, pears, plums, prunes, watermelon, and in some vegetables, including cauliflower, snow peas, and mange-tout peas.[25] Cabbage, chicory, and fennel contain moderate amounts, but may be eaten in a low-FODMAP diet if the advised portion size is observed.[26][better source needed][failed verification]

Polyols, specifically sugar alcohols, used as artificial sweeteners in commercially prepared food, beverages, and chewing gum, include isomalt, maltitol, mannitol, sorbitol, and xylitol.[7][23]

Fructose and lactose edit

People following a low-FODMAP diet may be able to tolerate moderate amounts of fructose and lactose, particularly if they have lactase persistence.[27]

Sources of fructose edit

Sources of lactose edit

Low-FODMAP diet edit

A low-FODMAP diet consists of the global restriction of all fermentable carbohydrates (FODMAPs),[7] and is recommended only for a short time. A low-FODMAP diet is recommended for managing patients with irritable bowel syndrome (IBS) and can reduce digestive symptoms of IBS, including bloating[28] and flatulence.[29]

Several studies have found a low-FODMAP diet to improve digestive symptoms in adults with irritable bowel syndrome,[8][9][10][11] but its long-term use can have negative effects, because it has a detrimental impact on the gut microbiota and metabolome.[2][9][11][12] It should only be used for short periods and under the advice of a specialist.[30] More study is needed to evaluate its effectiveness in children with irritable bowel syndrome.[8] Small studies (which are susceptible to bias) show little evidence of its effectiveness in treating functional symptoms of inflammatory bowel disease (IBD).[31][32] More study is needed to assess the true impact of this diet on health.[9][11]

Role in non-celiac gluten sensitivity edit

FODMAPs present in gluten-containing grains have been identified as a possible cause of gastrointestinal symptoms in people with non-celiac gluten sensitivity, either by themselves,[33] or in combination effect with gluten and other proteins in gluten-containing cereals, such as amylase-trypsin inhibitors (ATIs).[14][13] The amount of fructans in these cereals is small. In rye, they account for 3.6–6.6% of dry matter, 0.7–2.9% in wheat, and barley contains only trace amounts.[3] They are only minor sources of FODMAPs when eaten in common dietary amounts.[13] Wheat and rye may comprise a major source of fructans when consumed in large amounts.[7]

In a 2018 double-blind, crossover research study on 59 persons on a gluten-free diet with challenges of gluten, fructans, or placebo, intestinal symptoms (specifically bloating) were (borderline) significantly higher after challenge with fructans, in comparison with gluten proteins (P=0.049).[3][17] Although the differences between the three interventions were small, the authors concluded that fructans are more likely to cause gastrointestinal symptoms in non-celiac gluten sensitivity than gluten.[3] Fructans used in the study were extracted from chicory root, and the results may or may not apply to wheat fructans.[17]

A 2018 review concluded that although fructan intolerance may play a role in non-celiac gluten sensitivity, it only explains some gastrointestinal symptoms. Fructan intolerance does not explain the extra-digestive symptoms that people with non-celiac gluten sensitivity may develop, such as neurological disorders, fibromyalgia, psychological disturbances, and dermatitis. This review also found that FODMAPs may cause digestive symptoms when the person is hypersensitive to luminal distension.[3]

A 2019 review concluded that wheat fructans could cause certain IBS-like symptoms, such as bloating, but that they are not likely to cause immune activation or extra-digestive symptoms, as many people with non-celiac gluten sensitivity reported resolution of their symptoms after removing gluten-containing cereals. These same participants continued to eat fruits and vegetables with high FODMAP content without issue.[17]

See also edit

References edit

  1. ^ a b Gibson PR, Shepherd SJ (June 2005). "Personal view: food for thought — western lifestyle and susceptibility to Crohn's disease. The FODMAP hypothesis". Alimentary Pharmacology & Therapeutics. 21 (12): 1399–409. doi:10.1111/j.1365-2036.2005.02506.x. PMID 15948806. S2CID 20023732.
  2. ^ a b c Tuck CJ, Muir JG, Barrett JS, Gibson PR (September 2014). "Fermentable oligosaccharides, disaccharides, monosaccharides and polyols: role in irritable bowel syndrome". Expert Review of Gastroenterology & Hepatology. 8 (7): 819–34. doi:10.1586/17474124.2014.917956. PMID 24830318. S2CID 28811344.
  3. ^ a b c d e f g Verbeke K (February 2018). "Nonceliac Gluten Sensitivity: What Is the Culprit?". Gastroenterology. 154 (3): 471–473. doi:10.1053/j.gastro.2018.01.013. PMID 29337156. Although intolerance to fructans and other FODMAPs may contribute to NCGS, they may only explain gastrointestinal symptoms and not the extraintestinal symptoms observed in NCGS patients, such as neurologic dysfunction, psychological disturbances, fibromyalgia, and skin rash.15 Therefore, it is unlikely that they are the sole cause of NCGS.
  4. ^ a b Makharia A, Catassi C, Makharia GK (December 2015). "The Overlap between Irritable Bowel Syndrome and Non-Celiac Gluten Sensitivity: A Clinical Dilemma". Nutrients (Review). 7 (12): 10417–26. doi:10.3390/nu7125541. PMC 4690093. PMID 26690475.
  5. ^ a b Greer JB, O'Keefe SJ (2011). "Microbial induction of immunity, inflammation, and cancer". Frontiers in Physiology (Review). 1: 168. doi:10.3389/fphys.2010.00168. PMC 3059938. PMID 21423403.
  6. ^ a b Andoh A, Tsujikawa T, Fujiyama Y (2003). "Role of dietary fiber and short-chain fatty acids in the colon". Current Pharmaceutical Design (Review). 9 (4): 347–58. doi:10.2174/1381612033391973. PMID 12570825.
  7. ^ a b c d e f g h i j Gibson PR, Shepherd SJ (February 2010). "Evidence-based dietary management of functional gastrointestinal symptoms: The FODMAP approach". Journal of Gastroenterology and Hepatology. 25 (2): 252–8. doi:10.1111/j.1440-1746.2009.06149.x. PMID 20136989. S2CID 20666740. Wheat is a major source of fructans in the diet. (...) Table 1 Food sources of FODMAPs. (...) Oligosaccharides (fructans and/or galactans). Cereals: wheat & rye when eaten in large amounts (e.g. bread, pasta, couscous, crackers, biscuits)
  8. ^ a b c Turco R, Salvatore S, Miele E, Romano C, Marseglia GL, Staiano A (May 2018). "Does a low FODMAPs diet reduce symptoms of functional abdominal pain disorders? A systematic review in adult and paediatric population, on behalf of Italian Society of Pediatrics". Italian Journal of Pediatrics (Systematic Review). 44 (1): 53. doi:10.1186/s13052-018-0495-8. PMC 5952847. PMID 29764491.
  9. ^ a b c d e Staudacher HM, Irving PM, Lomer MC, Whelan K (April 2014). "Mechanisms and efficacy of dietary FODMAP restriction in IBS". Nature Reviews. Gastroenterology & Hepatology (Review). 11 (4): 256–66. doi:10.1038/nrgastro.2013.259. PMID 24445613. S2CID 23001679. An emerging body of research now demonstrates the efficacy of fermentable carbohydrate restriction in IBS. [...] However, further work is urgently needed both to confirm clinical efficacy of fermentable carbohydrate restriction in a variety of clinical subgroups and to fully characterize the effect on the gut microbiota and the colonic environ¬ment. Whether the effect on luminal bifidobacteria is clinically relevant, preventable, or long lasting, needs to be investigated. The influence on nutrient intake, dietary diversity that might also affect the gut microbiota, and quality of life also requires further exploration as does the possible economic effects due to reduced physician contact and need for medication. Although further work is required to confirm its place in IBS and functional bowel disorder clinical pathways, fermentable carbohydrate restriction is an important consideration for future national and international IBS guidelines.
  10. ^ a b Marsh A, Eslick EM, Eslick GD (April 2016). "Does a diet low in FODMAPs reduce symptoms associated with functional gastrointestinal disorders? A comprehensive systematic review and meta-analysis". European Journal of Nutrition. 55 (3): 897–906. doi:10.1007/s00394-015-0922-1. PMID 25982757. S2CID 206969839.
  11. ^ a b c d e Rao SS, Yu S, Fedewa A (June 2015). "Systematic review: dietary fibre and FODMAP-restricted diet in the management of constipation and irritable bowel syndrome". Alimentary Pharmacology & Therapeutics. 41 (12): 1256–70. doi:10.1111/apt.13167. PMID 25903636. S2CID 27558785.
  12. ^ a b Heiman ML, Greenway FL (May 2016). "A healthy gastrointestinal microbiome is dependent on dietary diversity". Molecular Metabolism (Review). 5 (5): 317–320. doi:10.1016/j.molmet.2016.02.005. PMC 4837298. PMID 27110483.
  13. ^ a b c d e Fasano A, Sapone A, Zevallos V, Schuppan D (May 2015). "Nonceliac gluten sensitivity". Gastroenterology (Review). 148 (6): 1195–204. doi:10.1053/j.gastro.2014.12.049. PMID 25583468. Cereals such as wheat and rye, when consumed in normal quantities, are only minor sources of FODMAPs in the daily diet. (...) Table 1. Sources of FODMAPs (...) Oligosaccharides (fructans and/or galactans). Cereals: wheat and rye when eaten in large amounts (eg, bread, pasta, couscous, crackers, biscuits)
  14. ^ a b Volta U, Caio G, Tovoli F, De Giorgio R (2013). "Non-celiac gluten sensitivity: questions still to be answered despite increasing awareness". Cellular and Molecular Immunology (Review). 10 (5): 383–392. doi:10.1038/cmi.2013.28. ISSN 1672-7681. PMC 4003198. PMID 23934026.
  15. ^ Ontiveros N, Hardy MY, Cabrera-Chavez F (2015). "Assessing of Celiac Disease and Nonceliac Gluten Sensitivity". Gastroenterology Research and Practice (Review). 2015: 1–13. doi:10.1155/2015/723954. PMC 4429206. PMID 26064097.
  16. ^ Priyanka P, Gayam S, Kupec JT (2018). "The Role of a Low Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyol Diet in Nonceliac Gluten Sensitivity". Gastroenterology Research and Practice. 2018: 1561476. doi:10.1155/2018/1561476. PMC 6109508. PMID 30158962.
  17. ^ a b c d Volta U, De Giorgio R, Caio G, Uhde M, Manfredini R, Alaedini A (March 2019). "Nonceliac Wheat Sensitivity: An Immune-Mediated Condition with Systemic Manifestations". Gastroenterology Clinics of North America (Review). 48 (1): 165–182. doi:10.1016/j.gtc.2018.09.012. PMC 6364564. PMID 30711208. Furthermore, a role for the FODMAP (eg, fructans) component of wheat as the sole trigger for symptoms is somewhat doubtful, because many patients with NCWS report resolution of symptoms after the withdrawal of wheat and related cereals, while continuing to ingest vegetables and fruits with high FODMAP content in their diets.59 On the whole, it is conceivable that more than one culprit may be involved in symptoms of NCWS (as they are currently defined), including gluten, other wheat proteins, and FODMAPs.60–62
  18. ^ Barrett JS (March 2017). "How to institute the low-FODMAP diet". Journal of Gastroenterology and Hepatology (Review). 32 (Suppl 1): 8–10. doi:10.1111/jgh.13686. PMID 28244669. Common symptoms of IBS are bloating, abdominal pain, excessive flatus, constipation, diarrhea, or alternating bowel habit. These symptoms, however, are also common in the presentation of coeliac disease, inflammatory bowel disease, defecatory disorders, and colon cancer. Confirming the diagnosis is crucial so that appropriate therapy can be undertaken. Unfortunately, even in these alternate diagnoses, a change in diet restricting FODMAPs may improve symptoms and mask the fact that the correct diagnosis has not been made. This is the case with coeliac disease where a low-FODMAP diet can concurrently reduce dietary gluten, improving symptoms, and also affecting coeliac diagnostic indices. Misdiagnosis of intestinal diseases can lead to secondary problems such as nutritional deficiencies, cancer risk, or even mortality in the case of colon cancer.
  19. ^ a b Ferraris RP, Choe JY, Patel CR (August 2018). "Intestinal Absorption of Fructose". Annual Review of Nutrition. 38: 41–67. doi:10.1146/annurev-nutr-082117-051707. PMC 6457363. PMID 29751733.
  20. ^ Storhaug CL, Fosse SK, Fadnes LT (October 2017). "Country, regional, and global estimates for lactose malabsorption in adults: a systematic review and meta-analysis". The Lancet. Gastroenterology & Hepatology. 2 (10): 738–746. doi:10.1016/S2468-1253(17)30154-1. PMID 28690131.
  21. ^ Bayless TM, Hanauer SB (2014). Advanced Therapy of Inflammatory Bowel Disease: Ulcerative Colitis. Vol. 1 (3rd ed.). PMPH-USA. pp. 250–. ISBN 978-1-60795-216-9.
  22. ^ a b c "The Monash University Low FODMAP diet". Melbourne, Australia: Monash University. 2012-12-18. Retrieved 2014-05-26.
  23. ^ a b c Gibson PR, Varney J, Malakar S, Muir JG (May 2015). "Food components and irritable bowel syndrome". Gastroenterology. 148 (6): 1158–74.e4. doi:10.1053/j.gastro.2015.02.005. PMID 25680668.
  24. ^ "New research: Enzyme therapy can help reduce symptoms in IBS patients sensitive to galacto-oligosaccharides (GOS) present in legumes, soy milk and nuts".
  25. ^ Lenhart A, Chey WD (July 2017). "A Systematic Review of the Effects of Polyols on Gastrointestinal Health and Irritable Bowel Syndrome". Advances in Nutrition. 8 (4): 587–596. doi:10.3945/an.117.015560. PMC 5508768. PMID 28710145.
  26. ^ Barrett J, McNamara L (2016-04-17). "Polyols - A blog by Monash FODMAP | The experts in IBS - Monash Fodmap". Retrieved 2023-07-08.
  27. ^ Usai-Satta P, Lai M, Oppia F (January 2022). "Lactose Malabsorption and Presumed Related Disorders: A Review of Current Evidence". Nutrients. 14 (3): 584. doi:10.3390/nu14030584. PMC 8838180. PMID 35276940. the impact of a lactose-restricted diet in patients with IBS is debated. Lactose is a component of the FODMAPs (highly fermentable oligo-, di-, monosaccharides and polyols) diet. Several studies confirmed the positive impact of a low FODMAP diet (LFD) in improving digestive symptoms in IBS. On the other hand, a lactose BT should be performed before an LFD in populations with a low prevalence of LM, avoiding an inappropriate exclusion of lactose in lactase-persistent IBS patients. Apart from FODMAPs, a lactose-restricted diet should be reserved for hypolactasic IBS patients. In conclusion, a restriction of lactose should be not systematically recommended in patients with IBS
  28. ^ Pessarelli T, Sorge A, Elli L, Costantino A. The low-FODMAP diet and the gluten-free diet in the management of functional abdominal bloating and distension. Front Nutr. 2022 Nov 8;9:1007716. doi: 10.3389/fnut.2022.1007716. PMID: 36424920; PMCID: PMC9678936.
  29. ^ "What Is a Low-FODMAP Diet". WebMD. Retrieved 16 December 2019.
  30. ^ Staudacher HM, Whelan K (August 2017). "The low FODMAP diet: recent advances in understanding its mechanisms and efficacy in IBS". Gut (Review). 66 (8): 1517–1527. doi:10.1136/gutjnl-2017-313750. PMID 28592442. S2CID 3492917.
  31. ^ Gearry RB, Irving PM, Barrett JS, Nathan DM, Shepherd SJ, Gibson PR (February 2009). "Reduction of dietary poorly absorbed short-chain carbohydrates (FODMAPs) improves abdominal symptoms in patients with inflammatory bowel disease-a pilot study". Journal of Crohn's & Colitis. 3 (1): 8–14. doi:10.1016/j.crohns.2008.09.004. PMID 21172242.
  32. ^ Hou JK, Lee D, Lewis J (October 2014). "Diet and inflammatory bowel disease: review of patient-targeted recommendations". Clinical Gastroenterology and Hepatology (Review). 12 (10): 1592–600. doi:10.1016/j.cgh.2013.09.063. PMC 4021001. PMID 24107394. Even less evidence exists for the efficacy of the SCD, FODMAP, or Paleo diet. Furthermore, the practicality of maintaining these interventions over long periods of time is doubtful. At a practical level, adherence to defined diets may result in an unnecessary financial burden or reduction in overall caloric intake in patients who are already at risk for protein-calorie malnutrition.
  33. ^ Ontiveros N, Hardy MY, Cabrera-Chavez F (2015). "Assessing of Celiac Disease and Nonceliac Gluten Sensitivity". Gastroenterology Research and Practice (Review). 2015: 1–13. doi:10.1155/2015/723954. PMC 4429206. PMID 26064097. The literature suggests that FODMAPs and not gluten per se are the triggers of gastrointestinal symptoms in patients that fit most of the proposed NCGS definitions

Further reading edit

External links edit