Assessing the Short-Term Effects of Multi-Fiber Supplementation on Gut Health

This is a randomized, parallel-group interventional study evaluating the short-term gastrointestinal effects of a standardized multi-fiber supplement in healthy adults. Approximately 100 participants (50 per arm) aged 18 and older will be randomized to receive either the multi-fiber supplement or a control (flavoring agent only) daily for 10 days. Objectives include assessing effects on stool characteristics, specifically frequency and consistency, as well as changes in metagenomically inferred short-chain fatty acid production potential from the microbiota. Eligible participants must be free of chronic disease, acute illness, and recent antibiotic, probiotic, or prebiotic use. Total participation duration is 10 days.

Inclusion Criteria: * in self-reported good health (i.e. no chronic disease, no acute illness) Exclusion Criteria: * chronic disease * acute illness * antibiotic, or probiotic, or prebiotic use in the prior 3 months * allergies to any of the following: psyllium husk powder, mustard, sesame, soy, tree nuts, pectin, citric acid, wheat, milk, egg, beta-glucan, barley, inulin, agave, resistant maltodextrin, arabinoxylan * adherence to any food-group strict diet (e.g. vegan, vegetarian, keto, etc.) * any of the following groups: adults unable to consent, individuals that are not yet adult, pregnant women, prisoners