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Controlled Feeding Experiment (CaFE)

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ClinicalTrials.gov Identifier: NCT00951756
Recruitment Status : Completed
First Posted : August 4, 2009
Last Update Posted : June 25, 2013
Information provided by (Responsible Party):

Study Description
Brief Summary:
The purpose of this study is to determine the effect of dietary fat, in standard formulation, on the composition of the human microbiome in a prospective study of normal volunteers. Participants will be randomly assigned to either a high fat or low fat diet for 10 days. The gut microbiome will be phylotyped in fecal samples as well as in bacteria adherent to the colonic mucosa prior to, and during the course of the dietary interventions.

Condition or disease Intervention/treatment
Effect of Diet on Microbiome Composition Other: High fat diet

Study Design

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 10 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single (Outcomes Assessor)
Primary Purpose: Basic Science
Official Title: Controlled Feeding Experiment of High and Low Fat Diet and Stool Microbiome Controlled Feeding Experiment of High and Low Fat Diet and Stool Microbiome Composition
Study Start Date : July 2009
Primary Completion Date : January 2010
Study Completion Date : August 2011
Arms and Interventions

Arm Intervention/treatment
High Fat Low Fiber Diet Other: High fat diet
High fat diet and low fat diet are composed of the same food, but the portion sizes are varied.
Low Fat High Fiber Diet Other: High fat diet
High fat diet and low fat diet are composed of the same food, but the portion sizes are varied.

Outcome Measures

Primary Outcome Measures :
  1. This is not an efficacy study. There is no pre-specified clinical endpoint for this study. Rather, the outcome is the composition of the gut microbiome. [ Time Frame: 10 days ]

Eligibility Criteria

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years to 40 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  1. Participant is capable of giving informed consent
  2. Participant is age 18 to 40 years

Exclusion Criteria:

  1. Diagnosis with Inflammatory bowel disease (IBD), celiac disease, or other chronic intestinal disorders.
  2. Baseline bowel frequency less than every 2 days or greater than 3 times daily.
  3. Current smoker.
  4. Body Mass Index (BMI) <18.5 of >35.
  5. Diabetes mellitus (DM)
  6. Diagnosis with coronary artery disease, congestive heart failure, or prior myocardial infarction.
  7. History of dyslipidemia or receiving treatment for hypercholesterolemia. This will be defined as a fasting LDL >160 mg/dL or a non-fasting total cholesterol >200 mg/dL or non-fasting HDL<40 mg/dl. Additionally, patients receiving drug therapy for hypercholesterolemia will be excluded.
  8. Prior bowel resection surgery.
  9. Contraindication to flexible sigmoidoscopy and biopsies. Patients with suppressed white blood count may be at increased risk of systemic infection following sigmoidoscopy with biopsies. As such, subjects with a white blood cell (WBC) count less than 3,500 or an absolute neutrophil count of less than 1,000 will be excluded. Patients with thrombocytopenia or with a coagulopathy may be at increased risk of bleeding complications after colonoscopic biopsies. As such, patients with a platelet count of less than 100,000 or an international normalized ratio (INR) greater than 1.2 will be excluded from the study.
  10. Student or employee of any one of the investigators.
  11. Pregnant women.
  12. Use of antibiotics in the prior 6 months.
  13. Use of antacids, non-steroidal anti-inflammatory drugs (NSAIDs), or dietary supplements in the preceding 2 weeks.
  14. Use of any of the following medications in the 4 weeks prior to randomization: proton pump inhibitors (PPI), histamine receptor antagonists, narcotics, tricyclic antidepressants, anticholinergics (e.g., hyoscamine), metoclopramide, anti-diarrhea medications, laxatives.
  15. HIV infection, AIDS, or other known conditions resulting in immunosuppression.
  16. Allergies or intolerance to the components of the study diets.
  17. Participant has experienced diarrhea within the two weeks prior to the first sigmoidoscopy. Diarrhea is defined as a change in bowel habits with an increased frequency or loose stools such that the stool could not be lifted with a fork.
  18. Any condition that the investigator feels may limit the volunteer's ability to complete the study protocol.
Contacts and Locations

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00951756

United States, Pennsylvania
University of Pennsylvania
Philadelphia, Pennsylvania, United States, 19104
Sponsors and Collaborators
James Lewis
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Principal Investigator: James D Lewis, MD, MSCE University of Pennsylvania
More Information

Responsible Party: James Lewis, Professor of Medicine and Epidemiology, University of Pennsylvania
ClinicalTrials.gov Identifier: NCT00951756     History of Changes
Other Study ID Numbers: DK83981
UH2DK083981 ( U.S. NIH Grant/Contract )
First Posted: August 4, 2009    Key Record Dates
Last Update Posted: June 25, 2013
Last Verified: June 2013

Keywords provided by James Lewis, University of Pennsylvania:
Dietary fat
Microbiome composition
Controlled feeding experiment