Traditional Dietary Advice Optimal as an Irritable Bowel Syndrome Therapy

March 7, 2022
Kenny Walter

Kenny Walter is an editor with HCPLive. Prior to joining MJH Life Sciences in 2019, he worked as a digital reporter covering nanotechnology, life sciences, material science and more with R&D Magazine. He graduated with a degree in journalism from Temple University in 2008 and began his career as a local reporter for a chain of weekly newspapers based on the Jersey shore. When not working, he enjoys going to the beach and enjoying the shore in the summer and watching North Carolina Tar Heel basketball in the winter.

Participants found the traditional dietary advice cheaper, easier to follow, and less time-consuming to shop than the gluten-free or low FODMAP diets.

A traditional diet might be the best option for patients with non-constipated irritable bowel syndrome (IBS).

A team, Anupam Rej, Academic Unit of Gastroenterology, Sheffield Teaching Hospitals NHS Foundation Trust, compared traditional dietary advice against the low FODMAP diet and gluten-free diet.


Different diets have been utilized as therapeutic options for non-constipated IBS. However, there remains a lack of sufficient and quality evidence on the efficacy on a lot of these diets.

In the study, the investigators examined patients with Rome IV-defined non-constipated IBS to be treated with either traditional dietary advice, the low FODMAP diet, or the gluten-free diet.

The investigators sought primary endpoints of the clinical response following 4 weeks of dietary intervention, defined by at least a 50 point reduction in the IBS symptom severity score (IBS-SSS).

Some secondary endpoints included changes in individual IBS-SSS items within clinical responders, acceptability and food-related quality of life with dietary therapy, changes in nutritional intake, alterations in stool dysbiosis index, and baseline factors associated with clinical response.


The results show 42% (n = 14) of the traditional dietary advice group met the primary endpoint, compared to 55% (n = 18) of the low FODMAP group and 58% (n = 19) of the gluten-free diet group (P = 0.43).

There was a similar improvement in IBS-SSS items regardless of the allocated diets.

However, there are some financial and other incentives for the different diets.

Overall, traditional dietary advice was cheaper (P <0.01), less time-consuming to shop (P <0.01), and easier to follow when eating out (P = 0.03) than the other 2 diets.

Traditional dietary advice was also easier to incorporate into daily life than the low FODMAP diet (P = 0.02).

There was a greater reduction in total FODMAP content in the low FODMAOP group (27.7g /day pre-intervention to 7.6 g/day at week 4) compared with the gluten-free diet (27.4/g/day to 22.4g/day) and traditional dietary advice (24.9 g/day to 15.2 g/day) groups (p <0.01).

In addition, reductions in micro- and macro-nutrient intake did not significantly differ between the 3 diets.

Also, alterations in stool dysbiosis index were similar between the diets, with 22-29% showing reduced dysbiosis, 35-39% no change, and 35-40% increased dysbiosis (P = 0.99). Baseline clinical characteristics and stool dysbiosis index did not predict a clinical response to dietary therapy.

“TDA, LFD and GFD are effective approaches in non-constipated IBS, but TDA is the most patient-friendly in terms of cost and convenience,” the authors wrote. “We recommend TDA as the first-choice dietary therapy in non-constipated IBS, with an LFD and GFD reserved according to specific patient preferences and specialist dietetic input.”

The study, “Efficacy and Acceptability of Dietary Therapies in Non-Constipated Irritable Bowel Syndrome: A Randomized Trial of Traditional Dietary Advice, the Low FODMAP Diet and the Gluten-Free Diet,” was published online in Clinical Gastroenterology and Hepatology.