Department of Food Science and Human Nutrition
Gainesville, Florida, 32611, United States
Active, Not Recruiting
NCT Number: NCT06911177
Yeast Mannans and Stool Frequency
Findings from an open-label pilot study of 20 adults suggested that supplementation with 15 g/day of yeast mannans was highly tolerable and demonstrated specific modulation of the microbiota and increased stool frequency in a subset of subjects reporting ≤1 stool per day at baseline. The primary aim of this randomized, double-blind, controlled trial is to determine if yeast mannan supplementation at 12 g/day will increase stool frequency in generally healthy adults reporting ≤1 stool per day. Secondary aims will determine the effect of yeast mannans on intestinal transit time, gastrointestinal symptoms, fecal microbiota composition, and urinary and fecal metabolomics.
Active, Not Recruiting
This study is active but is not currently recruiting participants.
Notify MeKey information
Conditions
Age range
18 year–90 year
Sex eligibility
All sexes
Study type
Interventional
Phase
Not applicable
Primary location
Who can participate
Healthy volunteers accepted: Yes
Only the study team can determine whether someone qualifies for participation.
Inclusion criteria
- Adults who report a stool frequency of ≤ 1 per day.
- Able to provide written informed consent in English.
- Willingness to consume 1 supplement (12 g of yeast mannans or control) daily for 28 days.
- Willingness to maintain their usual diet and physical activity patterns throughout the study and refrain from the consumption of any yeast-based foods (e.g. Marmite or Vegemite) or yeast extract supplements.
- Willing to comply with study procedures, including stool and urine colle
Exclusion criteria
- Stool frequency of < 3 per week
- Yeast allergy
- Vegan dietary pattern
- Self-reported kidney disease
- Elite athletes or long-distance runners
- Use of antibiotic drugs within 1 month of screening
- Current use of laxatives or antidiarrheal medications
- Use of other investigational products within 3 months of the screening
- Previously or currently being treated for intestinal diseases or conditions, including irritable bowel disease (i.e., IBS-D or IBS-mixed), Crohn's disease, ulcerative colitis, celiac disease, or gastrointestinal cancer.
- Previous gastrointestinal surgery (e.g., gastric bypass, fundoplication, bowel resection).
- Current cancer treatment.
- Currently pregnant.
Treatment and study plan
Yeast mannan
Dietary SupplementYeast cell wall fraction of manno-oligosaccharides and mannoproteins supplemented at 12 g/day.
Other names: yeast cell wall fraction
Control (placebo)
Dietary SupplementA supplement containing yeast protein, yeast extract, and maltodextrin, provided at 12 g/day.
Primary outcomes
-
Defecation frequency
Time frame: From enrollment to the end of treatment at 6 weeks.
Mean daily defecation frequency
Sponsors and collaborators
Lead sponsor
University of Florida
Other
Registry information
Official study title
Efficacy of Yeast Mannan Supplementation on Increasing Stool Frequency in Generally Healthy Adults: A Randomized Controlled Trial
Important dates
- Study start
- 2025
- Primary completion
- 2026
- Study completion
- 2026
- First posted
- Apr 4, 2025
- Registry last updated
- Apr 15, 2026
OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.
View the official ClinicalTrials.gov record (opens in a new tab)This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.