An interventional study of Urolithin A and Placebo in Healthy Volunteer, sponsored by National Institute on Aging (NIA). Recruiting at 1 site in United States. Open to participants aged 55 Years to 100 Years. Per ClinicalTrials.gov, last updated 2026-11-10.
Sponsored by National Institute on Aging (NIA) · Not applicable, Interventional, and Basic science
Background:
As people age, the cells in the pancreas that produce insulin begin to release less of this hormone, and levels of blood glucose (sugar) rise. This can lead to illnesses such as diabetes. Urolithin A (UA) is a natural nutritional supplement that may improve how the body controls blood glucose.
Objective:
To learn if UA improves levels of insulin and other hormones that help control blood glucose.
Eligibility:
People aged 55 years and older with a body mass index of 27 or higher.
Design:
Participants will have 6 clinic visits over 8 weeks.
Participants will be screened. They will have a physical exam with blood and urine tests and a test of their heart function.
UA gelcaps are taken by mouth every morning at home. Half of participants will take UA. The other half will take a placebo. The placebo looks like the study drug but does not contain any medicine. Participants will not know which they are taking.
Participants will have tests during the study including:
Oral glucose tolerance: Participants will drink a sweet liquid. Blood will be drawn at intervals over the next 3 hours.
Continuous glucose monitor: A sensor with a needle that goes just under the skin will be placed on the upper arm. Participants will wear this sensor throughout the study.
Exercise. Participants will walk on a treadmill while their heart rate, hearth rhythm, and blood pressure are monitored. They will walk in a hallway at normal and fast paces.
Imaging scans of the thigh; scans of the brain are optional....
Study Description:
We hypothesize that supplementation with the nutritional supplement urolithin A (UA) in healthy adults >= 55 years old will; (i) increase insulin secretion by boosting beta cell metabolism of glucose, resulting in increased ATP generation as pyruvate enters the TCA cycle after glycolysis, thereby enhancing early, acute insulin secretion and glucose uptake in skeletal muscle -both of which will lower circulating levels of blood glucose, (ii) boost production and secretion of incretin hormones because their secretion is also dependent on cellular depolarization, (iii) boost mitochondrial function in brain and muscle tissues. (iv) alter gut microbiome. These effects will be examined over an 8-week period. The study will include a Screening Visit and 5 additional study visits.
Objectives:
Primary Objective:
To determine if UA supplementation will increase the rate at which beta cells respond to glucose.
Secondary Objectives:
Investigate if UA alters incretin secretion in response to oral glucose (incretins are secreted only in response to nutrients) and uncover if UA increases brain and skeletal muscle metabolism.
Endpoints:
Primary Endpoint:
To determine if urolithin A supplementation will influence insulin secretion in response to oral glucose at 4 and 8 weeks after supplementation.
Secondary Endpoints:
2,969 studies on the registry are indexed under Insulin Resistance; 338 are open to participants now.
This study's planned enrollment of 180 is above the median of 40 across 2,369 interventional studies indexed under Insulin Resistance.
Browse Insulin Resistance studies →National Institute on Aging (NIA) is the lead sponsor of 160 studies on the registry; 13 are open to participants now.
Of its 7 completed or terminated interventional studies of FDA-regulated products, 2 (29%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
In order to be eligible to participate in this study, an individual must meet all of the following criteria:
EXCLUSION CRITERIA:
An individual who meets any of the following criteria will be excluded from participation in this study:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Autoimmune disease
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
GFR and eGFR (kidney filtering)
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hemoglobin (Hb)
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
50% of participants
Dietary Supplement: Placebo
50% of participants
Dietary Supplement: Urolithin A
Urolithin A (UA) is a widely available dietary supplement devoid of any known sided effects that is reported to improve mitochondrial function. The UA substance used in this investigation is regulated under Generally Recognized as Safe (GRAS) by the US FDA (GRN No. 000791) (https://www.fda.gov/media/120300/download) and is being advertised and sold as an oral supplement. The daily dose (1 gram) and duration (8 weeks) have already been tested in previous clinical trials.
The placebo will consist of methylcellulose and will appear identical to the active supplement. The placebo will be provided by the manufacturer of Urolithin A.
To determine if urolithin A supplementation will influence insulin secretion in response to oral glucose at 4 and 8 weeks after supplementation.
Study visits 1 - 5
Time frame: 8 weeks
To determine if UA supplementation will increase incretin secretion in response to oral glucose at 4 and 8 weeks after the supplementation.
Study visits 1 - 5
Time frame: 8 weeks
To determine if UA supplementation will enhance mitochondria respiration, based on p31 spectroscopy by thigh MRI/MRS at baseline and 8 weeks after supplementation.
Study visits 1 \& 5
Time frame: 8 weeks
To determine if UA will increase brain oxidative metabolism, based on brain MRS at baseline and 8 weeks after supplementation.
Study visits 1 \& 5
Time frame: 8 weeks
To determine if UA supplementation will alter gut microbiome composition.
Study visits 1, 3 \& 5
Time frame: 8 weeks
Plan to share: No
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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