Effects of Prolonged Fasting on Microbiome and HDL

September 25, 2018 updated by: University of California, Davis

The Effects of Prolonged Fasting on the Microbiome and HDL Particles of Human Subjects

Participants will undergo one day of habitual eating followed by 36 hours of water only fasting and final day of habitual eating of the exact same diet consumed on the first eating day. Blood draws will be performed on Day 1 in a 10-12 hr fasted state and 2 hour postprandial state and again on Day 3 in a 36hr fasted state and a 2 hour post prandial state. Microbiome samples and blood glucose data will be collected throughout the course of the study.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

Screening and Consent:

Prospective subjects who pass the initial phone screening interview (i.e. meet inclusion/exclusion criteria) will be admitted into the study and scheduled for a consent visit. At the consent visit, subjects who decide to participate will be given a series of questionnaires including a health history questionnaire, physical activity questionnaire, and will be asked to complete a 3-day diet record, to be completed before the baseline visit at the beginning of the study. Women who consent to participate will be scheduled to complete the study within the follicular phase and menses of the menstrual cycle to avoid confounding alterations in lipoproteins.

Study Visit1 (Baseline fasted):

On Day 1 of the study protocolstudy participants will report to the Ragle Human Nutrition Research Center located on the UC Davis campus (1283 Academic Surge, University of California, Davis, in Davis CA 95616) for a 12-hour overnight fasting blood draw and anthropometric measurements at approximately 8AM. Any participants that are found to have fasting glucose above or below 70-100mg/dL will be removed from the study. Study participants will be given a Precision Xtra Blood Ketone Testing Kit to collect blood ketone data during the fasting period of the study protocol, a set of stool collection kits to collect stool samples throughout the rest of the study protocoland fitted with a GoBe activity monitor to track physical activity throughout the rest of the study protocol. Proper use, care, and storage of the Precision Xtra systems, stool collection kits, and GoBe monitors will be explained in detail to study participants during the baseline visit. Study participants will be given a 24-hr food diary to record their food and beverage intake throughout the rest of the day or may be asked to track their diet using GB 360.

Study Visit 2 (Baseline postprandial):

After the baseline visit on Day 1 of the study protocol, study participants will go about their normal routines and eat their habitual diet ad libitum while recording their dietary intake throughout the day. This food record will be used in order for the study participants to mimic their food intake on Day 1 during the eating period on Day 3 of the study protocol. Study participants will eat their last meal of the day at approximately 6PM. Post-prandial blood samples will be collected at 2 hours after the ingestion of this last meal and immediately processed to yield patient plasma and isolated PBMCs to be stored for future analysis. These post-prandial samples will constitute the baseline "Fed" state of each participant. Study participants will also perform their first bloodprick for ketone measurement using the Precision Xtra Monitor under instruction and supervision by study personnel.

Fasting:

After ingestion of their final meal, participants will undergo a full 36 hours of fasting comprising Day 2 and the beginning of Day 3 of the trial without otherwise modifying their typical routine, including drinking coffee or tea (but with no creamers or sweeteners of any kind), if this is part of their normal routine. The time of the ingestion of the standardized meal will be used as the start point (0hr) for the continuous 36 hours of fasting. 36 hrs of fasting has been shown to be well tolerated in human subjects and was chosen for this trial as it represents the approximate amount of time that fasting would be experienced during a single cycle of an alternate day fasting regimen. Therefore, results from this study could be generalized to plan for future studies of alternate day fasting. Subjects will be encouraged to report any feelings of dizziness, headaches, nausea, or severe hunger that they may experience and, based on the severity of their conditions, will be advised whether or not to continue with the trial. Subjects will be asked to take small blood pricks starting immediately after waking up on Day 2 and then every 3 conscious hours thereafter using thePrecision Xtra Blood Ketone Testing Kits in order to test blood ketone levels during the fasting period. Ketone levels obtained from the blood pricks will be recorded automatically by the Precision Xtra monitor.

Study Visit 3 (Post 36h fasted):

At 36 hours of fasting, roughly 8AM on Day 3, subjects will return to the Ragle Center, perform a final blood prick for ketone monitoring by the Precision Xtra and their blood samples will be collected and again immediately processed and stored for future analysis constituting the "Fasted" state for each participant.

Study Visit 4 (Post 36h postprandial):

After the blooddraw at Study Visit 3, study participants will be allowed free access to food throughout the rest of the day and asked to eat an identical diet to the dietary intake the participants recorded on Day 1 in their 24 hour food diary. Subjects will eat their last meal at approximately 6PM. Post-prandial blood samples will be collected at 2 hours after the ingestion of this last meal and immediately processed to yield patient plasma and isolated PBMCs to be stored for future analysis. These post-prandial samples will constitute the "Refed" state of each participant. After this final blood draw, the Precision Xtra system will be collected, the GoBe removed, and the activity and ketone data collected throughout the course of the study will be transferred to a secure computer for analysis. Fasting compliance will be determined as 1) increasing or steady ketone levels throughout the 36hr fasting period and 2) the absence of significant drops in blood ketone levels, which would indicate food intake and noncompliance.

StoolCollection (Days 1-3):

Study participants will use the provided stool collection kits to collect stool samples from each bowel movement throughout the entire course of the study. Stool samples will be obtained from study participants at the Ragle Center as soon as possible after initial collection by study participants, frozen, and stored at -80C.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
21

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • California
      • Davis, California, United States, 95616
        • University of California Davis

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

20 years to 80 years (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

- Age: 20-40 years old to constitute a young study population; 60-80 years old to constitute an elderly study population

  • BMI: 19-27 kg/m2 to constitute a normal/healthy weight population
  • Weight: 133lbs or more
  • Fasting Glucose: 70-100mg/dL to ensure that fasting can be tolerated without inducing dangerously low levels of blood glucose
  • Subjects must be willing to undergo a period of 36 hours of water-only fasting
  • Subjects must be willing to collect samples of each bowel movement produced throughout the entire study period for microbiome analysis.
  • Subjects must be willing to collect and test blood pricks for blood glucose levels using a Contour Next ONE Blood Glucose Kit during the fasting stage of the study protocol.
  • Subjects must be willing to continuously wear a GoBe activity monitor throughout the course of the trial.

Exclusion Criteria:

  • Smoker
  • Anemia
  • Pregnancy or current breast-feeding
  • Documented chronic diseases including diabetes, thyroid disease, metabolic syndrome, cancer, or previous cardiovascular events
  • Any inflammatory bowel disease including IBS, Crohn's Disease, Celiac Disease
  • Consumption of >1 alcoholic drink/day
  • Current consumption of any probiotic or prebiotic supplements
  • Extreme dietary or exercise patterns
  • Recent weight fluctuations (greater than 10% in the last six months)
  • Regular use of over-the-counter allergy or pain medications (>1/week)
  • Taking prescription lipid medications (e.g. statins) or other supplements known to alter lipoprotein metabolism such as isoflavones.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Basic Science
  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: Fasting
Participants will undergo one day of habitual eating followed by 36 hours of water only fasting and final day of habitual eating of the exact same diet consumed on the first eating day. Blood draws will be performed on Day 1 in a 10-12 hr fasted state and 2 hour postprandial state and again on Day 3 in a 36hr fasted state and a 2 hour post prandial state. Microbiome samples and blood glucose data will be collected throughout the course of the study.
Other: Fasting
Participants will undergo one day of habitual eating followed by 36 hours of water-only fasting and final day of habitual eating consuming the exact same diet consumed on the first eating day. Blood draws will be performed on Day 1 in a 10-12 hr fasted state and 2 hour postprandial state and again on Day 3 in a 36hr fasted state and a 2 hour post prandial state. Microbiome samples and blood glucose data will be collected throughout the course of the study.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Change in HDL Immunomodulatory Capacity
Time Frame: Baseline fasted vs. Post 36 hours fasted
HDL will be isolated from plasma samples and HDL immunomodulatory capacity will be assessed in isolated HDL with an in vitro assay using stimulated macrophages.
Baseline fasted vs. Post 36 hours fasted

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Change in Gut Microbiome Composition
Time Frame: Baseline fasted vs. Post 36 hours fasted
Gut microbial composition will be assessed by sequencing of isolated DNA from stool samples.
Baseline fasted vs. Post 36 hours fasted

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
University of California, Davis

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Angela M Zivkovic, Ph.D., UC Davis

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
April 9, 2018

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
May 30, 2018

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
May 30, 2018

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
March 1, 2018

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
March 27, 2018

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
April 4, 2018

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
September 27, 2018

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
September 25, 2018

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
September 1, 2018

More Information

Terms related to this study

Keywords

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 918915

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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