Gluten may be OK for IBS
If you suffer from IBS or have worked with clients with IBS, you’ve likely heard of a low- FODMAP diet. The term FODMAP is a mouthful. FODMAPS are found in carbohydrates that contain fermentable oligo, di, monosaccharides and polyols. FODMAps are osmotic, so they pull water into the intestinal tract and may be poorly absorbed. Bacteria may ferment these types of sugars in the intestines and exacerbate IBS symptoms such as gas, bloating, abdominal pain or diarrhea. A list of FODMAP containing foods include:
Fructose (fruits, honey, high fructose corn syrup (HFCS), etc.)
Fructans (wheat, garlic, onion, inulin etc.)
Galactans (legumes such as beans, lentils, soybeans, etc.)
Polyols (sweeteners containing isomalt, mannitol, sorbitol, xylitol, stone fruits such as avocado, apricots, cherries, nectarines, peaches, plums, etc.) 1
The diet itself is not new. It was initially developed in Australia by the Monash University in 2005. Since then, a handful of studies have found it effective in reducing symptoms of IBS. A study from 2006 published in the Journal of the American Dietetic Association showed that 75% of patients that followed a low FODMAP diet indicated symptom improvement. 2 A 2011 study from the Journal of Human Nutrition and Dietetics found the low FODMAP diet offered an 86% better symptom response than usual IBS diet therapy. 3 The diet is not meant to be followed indefinitely. Those with IBS are advised to trial the diet for 4-6 weeks and work with a Registered Dietitian to gradually add foods back into the diet and keep a food diary to evaluate which foods trigger symptoms. The diet can be difficult to adhere to, especially if you eat out.4
There’s good news for those trying to follow a low FODMAP diet. Recent research suggests that a gluten-free diet may not be needed for many with IBS. Dr. Joanna Dionne, a gastroenterologist from the McMaster University in Hamilton, Ontario carried out a meta-analysis and systematic review of literature and sought randomized controlled trials that evaluated an exclusion diet versus alternative or usual diet. Trials to be included had to assess improvement in either global IBS symptoms or abdominal pain. There were nine studies that met the criteria: two focused on a gluten-free diet (n=111) and seven evaluated a low-FODMAP diet (n-=397). 4
Dr. Dionne and her researchers found that a gluten-free diet was associated with reduced global symptoms when compared to a control diet (RR = 0.42; 95%CL, 0.11-1.55), but the link was not statistically significant. In addition, it was found that a low-FODMAP diet was linked with reduced symptoms of IBS when compared to control diets (RR = 0.69, Cl, 0.54-0.88).4
Despite evidence to support the use of a low-FODMAP diet for IBS, Dionne and colleagues felt tat the quality of data used was not strong enough as the trials used different comparator groups and included a relatively small number of participants.
“The findings of this review demonstrate that, at present, there is insufficient evidence to recommend a [gluten-free diet] to reduce global IBS symptoms,” the researchers wrote. “There is very low-quality evidence that a low-FODMAP diet is effective in reducing global symptoms in IBS patients. More data are needed, but of the available dietary interventions, a low-FODMAP diet currently has the greatest evidence for efficacy in IBS.” 5
- Shepard, SJ. Et al. Fructose Malabsorption and Symptoms of Irritable Bowel Syndrome, Guidelines for effective dietary management. J Am Diet Assoc. 2006 Oct;106(10):1631-9.
- Staudacher HM, Whelan K, Irving PM, Lomer MC. Comparison of symptom response following advice for a diet low in fermentable carbohydrates (FODMAPs) versus standard dietary advice in patients with irritable bowel syndrome. J Hum Nutr Diet.2011 Oct;24(5):487-95.
- WhelanL. D. Martin H. M. Staudacher M. C. E. LomerThe low FODMAP diet in the management of irritable bowel syndrome: an evidence‐based review of FODMAP restriction, reintroduction and personalisation in clinical practice. J Hum Nutr Diet. 2018, Jan. 15.
- Dionne, et. al A Systematic Review and Meta-Analysis Evaluating the Efficacy of a Gluten-Free Diet and a Low FODMAPs Diet in Treating Symptoms of Irritable Bowel Syndrome. Am J Gastroenterol. 2018:doi:10.1038/s41395-018-0195-4.