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Completed

NCT Number: NCT04783142

A Study to Evaluate the Influence of Diet on GI Health

The purpose of this study is to understand the potential of protein and psyllium fiber to manipulate gut microbial densities, intestinal permeability, and inflammation in humans.

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Key information

Conditions

Healthy

Age range

18 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Mayo Clinic, Rochester, Minnesota, United States

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Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Adults ≥ 18 years old
  • On a baseline diet characterized by: Fiber intake of </= 20g/day, > 18% of daily calories from protein

Exclusion criteria

  • Prior history of gastrointestinal surgeries (except appendectomy and cholecystectomy)
  • Known diagnosis of inflammatory bowel disease (Crohn's or ulcerative colitis), microscopic colitis, celiac disease, or other inflammatory GI condition
  • Use of tobacco products within the past 6 months (since nicotine may affect intestinal permeability)
  • Use of NSAIDs or aspirin and unable or unwilling to stop taking two weeks prior to permeability test and for the duration of the study
  • Use of osmotic laxatives and unable or unwilling to stop taking one week prior to permeability test and for the duration of the study
  • Use of oral corticosteroids and unable or unwilling to stop use of oral corticosteroids within the previous 6 weeks and for the duration of the study
  • Multiple dietary restrictions or unable/unwilling to alter dietary protein or dietary fiber.
  • Unwilling to stop ingestion of alcohol and artificial sweeteners such as Splenda™ (sucralose), Nutrasweet™ (aspartame), sorbitol, xylitol, lactulose, or mannitol 2 days before and during the permeability testing days, e.g. foods to be avoided are sugarless gums or mints and diet beverages
  • Unwilling to stop stenuous exercise (running >5 miles or equivalent) one week prior to the permeability tests
  • Bowel preparation for colonoscopy less than one week prior to completion of the first stool kit and permeability test and flexible sigmoidoscopy and upper endoscopy
  • Pregnancy or plan to become pregnant during the study time frame
  • Vulnerable adult
  • Known bleeding disorders or takes medications that increase risk of bleeding from mucosal biopsies
  • Use of oral antibiotic(s) within the past 4 weeks (can be enrolled after 4-week washout period)
  • Use of commercial probiotic formulations and unwilling to stop for the duration of the study
  • Diagnosis of diabetes
  • Any other disease(s), condition(s) or habits(s) that would interfere with completion of study, or in the judgment of the investigator would potentially interfere with compliance to this study or would adversely affect study outcomes

Treatment and study plan

High-fiber, low-protein diet

Other

Diet will consist of at least 15g fiber above baseline and less than 10% of calories from protein.

Low-fiber, high-protein diet

Other

Diet will consist of less than 15g fiber and greater than 18% of calories from protein

Primary outcomes

  1. Urinary Excretion of Lactulose and 13C-Mannitol

    Time frame: 4 weeks

    Small Bowel and Colonic Permeability by Urinary Excretion of Lactulose and 13C-Mannitol after Oral Ingestion of lactulose and 13C mannitol (5:1 ratio by mass). The 0-2h urine most closely reflects small intestinal permeability and 8-24h urine reflects colonic permeability. HPLC-tandem mass spectrometry will be used for detection of the sugars. The results will be expressed as the ratio of percentage excretion of the ingested dose of lactulose and mannitol in urine.

Secondary outcomes

  1. Change in gut microbial alpha diversity based on Shannon index

    Time frame: 4 weeks

    Stool samples will be processed to extract DNA, followed by metagenomic sequencing and assessment of alpha diversity using Shannon index. Comparison will be made using ttest.

Sponsors and collaborators

Lead sponsor

Mayo Clinic

Other

Registry information

Official study title

The Influence of Diet on Host Physiology and Disease Across Diverse Human Gut Microbiotas

Important dates

Study start
2021
Primary completion
2023
Study completion
2023
First posted
Mar 5, 2021
Registry last updated
May 15, 2023

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.

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