Fiber Gels Reduce Gut Gas From Fermentable Foods in Healthy Adults
Clinical Trial: Randomised Placebo-Controlled Trial of Methylcellulose and Psyllium Gels on Inulin-Induced Colonic Gas
Research hubs: Digestive System
- Authors
- Neele Dellschaft, Alaa Alhasani, Joshua E S J Reid, Caroline L Hoad, Elizabeth Gates, Molly Whymark, Gleb Yakubov, Luca Marciani, Frederick J Warren, Amisha Modasia, Abi Spicer, Colin Crooks, Maura Corsetti, Penny A Gowland, Robin Spiller
- Journal
- Alimentary Pharmacology & Therapy
- Year
- 2026
- DOI
- 10.1111/apt.70964
- Study Type
- Human
- Outcome
- Neutral
- Peer Reviewed
- Yes
- Country
- United Kingdom
- Health Condition
- Irritable Bowel Syndrome (IBS)
- Body System
- Gastrointestinal
TL;DR
Methylcellulose and psyllium reduced inulin-related colonic gas in healthy adults; this was not a molecular-H₂ intervention study.
Key Finding
Both methylcellulose and psyllium reduced colonic gas from inulin fermentation after reaching the colon, and methylcellulose retained significantly more water throughout the intestine than psyllium.
Summary
This study tested whether two gel-forming fibers — methylcellulose and psyllium — could reduce the intestinal gas produced when people digest inulin, a type of carbohydrate (sugar chain) that gut bacteria ferment. Twenty-two healthy volunteers each tried all three conditions (methylcellulose, psyllium, or a placebo) in a randomized order, with MRI scans and breath hydrogen measurements used to track gas and water in the gut. Both fibers reduced colonic (large intestine) gas once they reached that part of the gut, and methylcellulose held more water in both the small and large intestine than psyllium did.
Practical Takeaway
This study is relevant to hydrogen water consumers primarily as context: it uses breath hydrogen as a measure of gut fermentation, not as a therapy. The findings suggest that gel-forming fibers may help manage digestive gas and discomfort related to fermentable carbohydrates, but this study does not address hydrogen water and should not be interpreted as supporting its use.
Abstract (excerpt)
Background: People with irritable bowel syndrome (IBS) often restrict their intake of FODMAPs because of associated gas and abdominal discomfort. Psyllium, a gel-forming fibre, reduces colonic gas after inulin ingestion. Objective: We aimed to determine whether methylcellulose, a low-cost…