NCT07527208 · Cornell University
The Meta-SHIFT Study: How Metabolic Shift Shapes Human Immunometabolism - a Fasting Trial
(Meta-SHIFT)
What this study is about
During fasting, the body shifts from using carbohydrates to relying more on fat as its main source of energy. This process is known as the 'metabolic shift'. Fat tissue helps supply this energy by breaking down stored fat into fatty acids, which are released into the bloodstream and transported to organs throughout the body.
View original scientific description
During fasting, the body shifts from using carbohydrates to relying more on fat as its main source of energy. This process is known as the 'metabolic shift'. Fat tissue helps supply this energy by breaking down stored fat into fatty acids, which are released into the bloodstream and transported to organs throughout the body. In addition to fatty acids, many other substances in the blood (such as metabolites) change during fasting to help maintain normal body function. Immune cells also circulate in the blood and play an important role in protecting the body against infections and diseases such as cancer. However, it is not yet well understood how the metabolic shift during fasting affects immune cell function. The purpose of this study is to investigate how 24 hours of fasting influences immune cell metabolism and function.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Apparently healthy
- Age 18-40y at the time of recruitment
- BMI ≥ 18.5 and ≤ 24.9 kg/m2
- Willing to participate in all study activities during the 3-day intervention
- Signed informed consent
Exclusion criteria
- Diagnosed with any chronic medical condition that can interfere with the study outcome (e.g., cardiovascular disease, cancer, diabetes mellitus type 1 or 2, liver disease, pulmonary disease, renal disease, inflammatory bowel disease, thyroid disease, long COVID, PASC)
- Bleeding disorder (e.g., Hemophilia A/B, Von Willebrand Disease, or low platelets), current anemia or current use of blood thinners or anticoagulants (e.g. warfarin, heparin)
- Any acute or chronic infection disease or fever in the past month
- Antibiotic use in the past 2 months
- Use of any prescribed medications (incl. GLP-1 agonists), except for contraceptives
- Usage of recreational drugs in the last three months
- Unstable body weight (weight gain or loss \>5% of total BW in the past three months)
- Following any restrictive diet within one month of starting the study (for example a ketogenic diet or weight loss diet)
- Fasted for 16 hours or longer in the past week
- History of an eating disorder (e.g., anorexia nervosa, bulimia nervosa, or binge eating disorder)
- Allergic to one or more components of the standardized meal and/or shake (i.e., milk, wheat, and soy)
- Average alcohol intake that exceeds 1 consumption/day or 7 consumptions/week over the past month
- Tobacco smoker or regular use of nicotine products
- Donated or intend to donate blood from 2 months before the study until the end of the study
- Being pregnant or lactating
- Participation in another biomedical study during this study
Where
- Ithaca, New York
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced May 7, 2026 · Source of record for eligibility and locations