AzTrials
AzTrials

Pre DiabetesNCT03919877

Precision Diets for Diabetes Prevention

A study testing Dietary and Oral Food Challege in people with Pre Diabetes and Insulin Resistance, run by Stanford University at 1 site in United States.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
Search all trials

Trial summary

With this study the investigators want to understand the physiological differences for people developing pre-diabetes and diabetes. The investigators hypothesize that different individuals go through different paths in the development of the disease. Read more about this study

Who is it for?
Ages 18 years and olderHealthy volunteers can take part
What is being tested?
Dietary and Oral Food Challege
Could I receive a placebo?
No, everyone receives an active treatment
How many people
115 participants
Where
1 siteUnited States
Study dates
24 May 2018to 18 Oct 2023
Phase
Interventional
Are there results?
Yes, posted in the registrySummary in the doctors' view

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 18 years and older
  • All sexes
  • Healthy volunteers accepted
  • Adult, Older adult

Who may be able to join

  • Be 18 years of age or older;
  • Not be pregnant, if female;

Who cannot join

  • Have major organ disease, hypertension defined as >160/100, pregnant/lactating, diabetogenic medications, malabsorptive disorders like celiac sprue, others, heavy alcohol use, use of weight loss medications or specific diets, weight change > 2 kg in the last three weeks, history of bariatric surgery.
  • Any medical condition that physicians believe would interfere with study participation or evaluation of results.
  • Mental incapacity a nd/or cognitive impairment on the part of the patient that would preclude adequate understanding of, or cooperation with, the study protocol.

Trial locations and contacts

1 site in 1 country.

United States1 site

  • Stanford University

    Stanford, California, 94304

Other trials in United States

About this study

With this study the investigators want to understand the physiological differences for people developing pre-diabetes and diabetes. The investigators hypothesize that different individuals go through different paths in the development of the disease. By understanding the personal mechanism for developing disease, the investigators will find a personalized approach to prevent that development. The investigators are also hoping to be able to find a biomarker that will pinpoint to the particular defect and thus, diagnose the problem at an earlier stage and have the information to give personalized diet recommendations to prevent the development of diabetes more effectively.

Read the detailed description

At present, individuals with prediabetes or diabetes are grouped together as a single entity, but almost certainly they represent a mix of different gene-environment interactions that lead to one of four dominant physiologic mechanisms underlying their dysglycemia. 1- liver insulin resistance, 2- muscle insulin resistance, 3- impaired insulin secretion, 4- impaired incretin hormone secretion. Gaps that we are addressing here are extremely important - first, we will define a composite biomarker to identify different subphenotypes of prediabetes based on the four known physiologic mechanisms that contribute differentially in each individual to glucose elevations, which we hypothesize will also be reflected in their "glucotype". Importantly, because both continuous glucose monitor and administration of standardized meal testing and metabolic tests are not practical in the clinic, the development of a composite biomarker comprised of select multi-omics measures and clinical variables will enable clinicians and possibly patients (without clinician) to easily identify the specific diet that will yield optimal health results.

Being tested
Dietary, Oral Food Challege
Medical subject headings
Glucose Intolerance, Insulin Resistance, Diabetes Mellitus, Type 2

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • DietaryOther

    Dietary counseling based on results of CGM analyses.

  • Oral Food ChallegeOther

    Participants ate a variety of foods, to assess their impact on blood sugars.

Study groups in NCT03919877
Study groupRoleWhat they receive
Optimizing Diet for Glycemic ControlOtherPhase 1: Metabolic testing will include 3 metabolic tests: 1. The Oral Glucose Tolerance Test. The participant will wear the CGM while undergoing the OGTT + will be asked to repeat the test at home twice. 2. The Insulin Sensitivity Test (Steady State Plasma Glucose). This test is designed to measure how well cells remove glucose from the blood in response to insulin. 3. The Isoglycemic Intravenous Glucose Infusion (IIGI). This test is designed to measure the incretin hormone effect. Phase 2: Participants follow their own diet while using the CGM. Participants are provided with 5-10 standardized foods to test during this phase. Phase 3: Participants are provided with additional standardized foods and counseled to continue their own diet during this phase. Phase 4: Participants are counseled on reducing or limiting the foods that caused glucose spikes and they are also counseled on macronutrient composition of their diet based on lipid profile.
Receives: Other: Dietary; Other: Oral Food Challege

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Change in Glycemic Control as Measured by Change Blood Sugar Values

    Change in glycemic control measured from baseline through all phases of study, stratified according food type and metabolic sub-type. Glycemic control is derived from continuous glucose monitor (CGM) data and expressed in milligrams/deciliter.

    Measured: Assessed at a meal (2 to 6 weeks after baseline), starting just prior eating, for a period of 3 hours

  2. Area Under the Receiver Operating Characteristic (ROC) Curve - Classification of Metabolic Subphenotype

    Classify metabolic subphenotype in individuals without diabetes using a machine learning algorithm applied to the glucose time-series response generated by a 16-point (blood draws) oral glucose tolerance testing (OGTT) done in the clinical research center and at home (using CGM). Participants were categorized as insulin sensitive (IS) if teady state plasma glucose (SSPG) was <120 mg dl-1 and insulin resistant (IR) if their SSPG was ≥120 mg dl-1. For this analysis, disposition index (DI) < 1.58 indicates dysfunctional β-cell function, whereas DI ≥ 1.58 indicates normal β-cell function.

    Measured: Baseline (Day 1)

Secondary outcomes (1)

  1. Change in Area Under the Curve (AUC) of Blood Glucose Level

    Measured from baseline through all phases of study, from continuous glucose monitor (CGM) data, and stratified according food type and metabolic sub-type.

    Measured: Assessed at a meal (2 to 6 weeks after baseline), starting just prior eating, for a period of 3 hours

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted18 Apr 2019
  2. Study start24 May 2018
  3. Primary completion18 Oct 2023
  4. Study completion18 Oct 2023

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase N/A
Primary purpose
Prevention
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrolment
115 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT03919877
Sponsor's protocol ID
43883
Other IDs
5RM1HG007735-09
Status last verified
Apr 2026
First submitted
20 Dec 2018
Last updated
22 May 2026
Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No

Publications

  • Wu Y, Ehlert B, Metwally AA, Perelman D, Park H, Brooks AW, Abbasi F, Michael B, Celli A, Bejikian C, Ayhan E, Lu Y, Lancaster SM, Hornburg D, Ramirez L, Bogumil D, Pollock S, Wong F, Bradley D, Gutjahr G, Rangan ES, Wang T, McGuire L, Venkat Rangan P, Raeder H, Shipony Z, Lipson D, McLaughlin T, Snyder MP. Individual variations in glycemic responses to carbohydrates and underlying metabolic physiology. Nat Med. 2025 Jul;31(7):2232-2243. doi: 10.1038/s41591-025-03719-2. Epub 2025 Jun 4.

    PubMed 40467897

  • Metwally AA, Perelman D, Park H, Wu Y, Jha A, Sharp S, Celli A, Ayhan E, Abbasi F, Gloyn AL, McLaughlin T, Snyder MP. Prediction of metabolic subphenotypes of type 2 diabetes via continuous glucose monitoring and machine learning. Nat Biomed Eng. 2025 Aug;9(8):1222-1239. doi: 10.1038/s41551-024-01311-6. Epub 2024 Dec 23.

    PubMed 39715896

  • Park H, Metwally AA, Delfarah A, Wu Y, Perelman D, Mayer C, McGinity C, Rodgar M, Celli A, McLaughlin T, Mignot E, Snyder M. High-resolution lifestyle profiling and metabolic subphenotypes of type 2 diabetes. NPJ Digit Med. 2025 Jun 11;8(1):352. doi: 10.1038/s41746-025-01728-6.

    PubMed 40500312

Questions about this trial

What is this clinical trial studying?

A study testing Dietary and Oral Food Challege in people with Pre Diabetes and Insulin Resistance, run by Stanford University at 1 site in United States.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 2 inclusion and 3 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 22 May 2026. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

Yes. Results are posted in the registry (first posted 22 May 2026). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Change in Glycemic Control as Measured by Change Blood Sugar Values (time frame: Assessed at a meal (2 to 6 weeks after baseline), starting just prior eating, for a period of 3 hours). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT03919877, which also lists 3 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 22 May 2026; AzTrials last refreshed its copy on 26 Oct 2026.

AzTrials uses cookies for analytics and advertising. You can accept or reject them; the site works either way. Privacy Policy.

Free account

Keep searching with a free account

You’ve used your 3 free searches for this session. Log in or create a free AzTrials account to keep searching clinical trials and save the ones you want to follow.

Create a free accountLog in