NCT06954675 · University of California, San Francisco
Comparison of Microbiome Changes in Healthy Adults Following Ketone Ester Consumption
(BREAK)
What this study is about
The goal of this observational study is to learn if a ketone ester can improve the content of the gut microbiome.
View original scientific description
The goal of this observational study is to learn if a ketone ester can improve the content of the gut microbiome.
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
- Subject is male or female, 18 to 40 years of age, inclusive, at Virtual Visit 1.
- Subject has a self-reported BMI of 18.5 to 39.9 kg/m2 (inclusive) at Virtual Visit 1.
- Subject is willing and able to comply with all study procedures including maintenance of habitual dietary intake, consumption of study product at specified intervals, written questionnaires including study log and beverage tolerability questionnaire (KETQ), habitual exercise and medication and supplement use.
- Subject has an email address and internet access via computer, phone, or other device, and is willing and able to maintain internet access throughout the trial to complete virtual visits via video conference.
- Subject has no health conditions that would prevent them from fulfilling the study requirements as judged by the Study Clinician on the basis of medical history.
- Subject understands the study procedures and signs forms providing informed consent to participate in the study.
Exclusion criteria
- Subject is unable to converse in English or Spanish
- Subject is unable to provide informed consent due to cognitive impairment or insufficient English or Spanish language comprehension
- Subject has been hospitalized within 30 days of Virtual Visit 1.
- Subject has a history or presence of uncontrolled and/or clinically active pulmonary, cardiac (e.g. \>= New York Heart Association class III), hepatic, renal, endocrine (including type 1 diabetes), hematologic, immunologic, neurologic (e.g., Alzheimer's or Parkinson's diseases), psychiatric (including unstable depression and/or anxiety disorders) or biliary disorders. Stable chronic disease is not an exclusion criterion unless specified.
- Subject has a clinically important gastrointestinal condition that would potentially interfere with the evaluation of the study beverage \[e.g., inflammatory bowel disease, irritable bowel syndrome, chronic constipation, severe constipation (in the opinion of the Study Clinician), history of frequent diarrhea, history of surgery for weight loss, gastroparesis, systemic disease that might affect gut motility according to the Study Clinician, reflux requiring daily medication, history of gastrointestinal ulcers or bleeding, celiac disease, and/or clinically important lactose intolerance\].
- Subject has a known allergy, intolerance, or sensitivity to any of the ingredients in the study product, including milk protein.
- Subject is undergoing treatment or active surveillance for cancer, or has been diagnosed with cancer in the prior two years, except for non-melanoma skin cancer.
- Subject has recently used antibiotics within 60 days of Virtual Visit 1.
- Subject has extreme dietary habits (e.g., intermittent fasting or time restricted eating, Atkins diet, vegan, very high protein/low carbohydrate or has used weight-loss medications (including over-the-counter medications and/or supplements) or programs within 30 days of Virtual Visit 1.
- Subject has used medications (over-the-counter or prescription) known to influence gastrointestinal function including, but not limited to, opioids, weight loss medications, antidiarrheals, and antispasmodics) within 30 days of Virtual Visit 1.
- Subject has used ketone supplements (ketone salts or esters, and medium chain triglycerides \[MCT\]) within 30 days of Virtual Visit 1.
- Subject is a female who is pregnant, planning to be pregnant during the study period, lactating, or is of childbearing potential and is unwilling to commit to the use of a medically approved form of contraception throughout the study period. The method of contraception must be recorded.
- Subject has a condition the Study Clinician believes would interfere with their ability to provide informed consent, comply with the study protocol, which might confound the interpretation of the study results, or put the subject at undue risk.
Where
- San Francisco, California
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 Jan 26, 2026 · Source of record for eligibility and locations