IRRITABLE BOWEL SYNDROME AND FODMAP
With 1 in 7 Australian adults now diagnosed with Irritable Bowel Syndrome (IBS), recent gastroenterological research has given the dietary intervention, FODMAPs much attention in regards to the management of the IBS symptoms.
Dietary interventions have long played a vital role in the management of an IBS patient by naturopaths.
Abdominal distension is the physiological basis of many functional gastrointestinal symptoms and not only presents itself as visible such as bloating, but also induces symptoms of pain and can contribute to changes in motility.
The term ‘FODMAP’ is an acronym for Fermentable Oligosaccharides, Disaccharides, Monosaccharides and Polyols.
The poor absorption of FODMAP-enriched foods in the small intestine plays a primary role in the development of IBS. FODMAP-containing foods vary significantly; however it consists predominantly of food like artichokes, asparagus, leeks, garlic, onions, wheat , barley , lactose (milk sugar), fructose (fruit sugar), sorbitol and xylitol both used as natural sugar alternatives, galactans in food like beans, chickpeas, lentils, cabbage, Brussels sprouts, to name the most well known “trouble makers”.
The influence of the poor absorption of FODMAPs is two-fold –
1) The increased intestinal concentration influences water retention in the intestine
2) The metabolism of FODMAP by intestinal bacteria
They are molecules that attract water into the lumen via the process of osmosis; this accumulation of water in the intestinal lumen can potentiate a laxative effect thereby increasing the liquidity of luminal contents and the subsequent effect on overall gut motility. Finally, the chain length of carbohydrates are known to dictate the rapidity of their fermentation by intestinal bacteria; short chain carbohydrates, such as FODMAPs, are more rapidly fermented by unbalanced bacteria in the colon, which enhances the production of methane, dioxide, hydrogen and carbon that are the main contributors to IBS symptoms such as bloating and flatulence.(1)
The first research trial conducted on FODMAP foods and Irritable Bowel Syndrome (IBS) from Monash University in 2006 showed an astounding 74% of all IBS sufferers reporting a substantial improvement in all abdominal symptoms.(2) In this trial, 62 professionally-diagnosed IBS patients underwent dietary modulation over a median period of 14 months. Results were gathered by self-reported symptom scaling questionnaires, and showed that those participants who strictly adhered to the low FODMAP diet yielded a more promising improvement in symptoms overall.
The trial also concluded that foods containing glucose and sucrose in equal amounts to fructose were not considered problematic since fructose is absorbed in the presence of glucose. The exciting and revolutionary research Monash University is currently undertaking in the field of dietary management of IBS is of upmost importance to all complementary alternative practitioners.
IBS is the most common gastroenterological symptom presentation seen in clinical practise, so research trials done in this specific area are significant for practitioners when considering their individualised treatment plans. The FODMAPs approach is setting a precedent in evidence-based dietary intervention that has yet to be seen in nutritional practise.
Traditional dietary interventions have now been challenged by strongly validated clinical trials which will see modern-day evidence-based practitioners re-directing their scope of prescription towards this dietary approach.
Clinician Note: Low FODMAP diets often result in low dietary fibre intake and low short chain fatty acid production. Slippery Elm is both high in fibre and provides prebiotic properties. In addition to this, a combination of Slippery Elm, Glutamine, and Pectin with immunomodulatory microorganism – a very specific probiotic like Saccharomyces boulardii may be an effective clinical nutritional intervention for IBS patients prescribed a low FODMAPs diet.
(1) Gibson PR, Shepherd SJ, Evidence-based dietary management of functional gastrointestinal symptoms: The FODMAP approach. Journal of Gastroenterology and Hepatology; 2010:25-252-258
(2) Gibson PR, Shepherd SJ, Food Choice as a Key Management Strategy for Functional Gastrointestinal Symptoms. American J of Gastroenterology;2012:107;657-666