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Effects of a Dietary Fiber on Fecal Microbiota and Metabolism

This study has been completed.
Information provided by (Responsible Party):
National Starch LLC Identifier:
First received: January 20, 2012
Last updated: April 20, 2016
Last verified: January 2012
The purpose of the study is to examine how a dietary fiber affects metabolism in healthy overweight and obese adults. The fiber will be added to foods that participants will consume for two, three-week periods. The fiber will be given in two doses -- 15 g per day during one period, and 30 g per day in the other. In another three-week period, they will consume the same foods, but with no fiber added. Major outcomes will include fermentability of the fiber, as assessed by measurement of breath hydrogen, as well as shifts in fecal bacteria. The caloric value of the fiber will be determined and metabolic measures related to blood glucose control and inflammation will also be taken.

Condition Intervention
Focus of the Study is on Gut Health
Dietary Supplement: Dietary Fiber

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double Blind (Participant, Outcomes Assessor)
Primary Purpose: Prevention
Official Title: Effects of a Dietary Fiber on Human Gut Microbiota, Bioactive Metabolites and Blood Glucose Control

Resource links provided by NLM:

Further study details as provided by National Starch LLC:

Primary Outcome Measures:
  • Metabolizable energy [ Time Frame: 7 days, 3 times ]
    Urine and feces will be collected for 7 days at the end of each treatment period to allow for assessment of metabolizable energy

  • Fermentability [ Time Frame: One, eight-hr day, three times ]
    Breath hydrogen will be measured hourly, over eight hours at the end of each treatment period

Secondary Outcome Measures:
  • Fecal microbiota [ Time Frame: 2 days, three times, and 7 days, three times ]
    Fecal samples will be collected for 7 days at the end of each treatment period and for two days during washout periods

  • Blood glucose [ Time Frame: For eight hours, three times ]
    An indwelling catheter will be placed and blood samples will be drawn over the course of an eight-hour period, at the end of each treatment period

Enrollment: 20
Study Start Date: February 2012
Study Completion Date: December 2013
Primary Completion Date: December 2013 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Low dose dietary fiber Dietary Supplement: Dietary Fiber
Dietary fiber will be added to study foods
Experimental: High dose dietary fiber Dietary Supplement: Dietary Fiber
Dietary fiber will be added to study foods
Placebo Comparator: No added fiber Dietary Supplement: Dietary Fiber
Dietary fiber will be added to study foods


Ages Eligible for Study:   20 Years to 60 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Body mass index from 25 to 35 kg/m2.
  • Willing to consume study foods and comply with dietary exclusions and specimen collection

Exclusion Criteria:

  • Pregnancy
  • Diabetes
  • Gastrointestinal disease
  • Regular use of pre- or probiotics
  • Recent use of antibiotics
  • High intake of dietary fiber
  Contacts and Locations
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Please refer to this study by its identifier: NCT01518088

United States, California
USDA, ARS, Western Human Nutrition Research Center
Davis, California, United States, 95616
Sponsors and Collaborators
National Starch LLC
Principal Investigator: Nancy Keim, PhD ARS/USDA, University of California - Davis
  More Information

Responsible Party: National Starch LLC Identifier: NCT01518088     History of Changes
Other Study ID Numbers: PRT002
Study First Received: January 20, 2012
Last Updated: April 20, 2016 processed this record on May 22, 2017