This study is testing the feasibility of using non-invasive, remote digital tools including continuous glucose monitors (CGMs) and the Oura Ring to predict the function of beta-cells, the cells in the pancreas that secrete insulin. This study is being done in individuals with prediabetes or Type 2 diabetes. The aim is to develop remote digital tools that can predict the health and functioning of the pancreas in people with prediabetes or Type 2 diabetes, allowing personalized treatment approaches to preserve insulin secretion.

The objective of this research is to construct a real-time, non-invasive predictor of pancreatic beta-cell function for individuals with T2D or prediabetes, using data from a CGM alongside a diverse array of health, lifestyle, and behavioral metrics gathered via a smartphone app and Oura Ring. Investigators will study individuals with T2D or prediabetes using remote digital tools to determine the risk of conversion from prediabetes to T2D as it relates to beta-cell function, as well as personalized treatment options for individuals with Type 2 diabetes. Participants will undergo detailed evaluations of pancreatic beta-cell function at the Buck Institute's Clinical Research Unit (CRU) using the Minimal Model Oral Glucose Tolerance Test (OGTT) with analysis of C-peptide, glucose and insulin levels, and a Meal Tolerance Test (MTT) at the end of the study. Participants will complete 4 at-home real-world challenges that will also involved MTTs with or without a controlled psychological stress test that will be administered to you by research staff. From this data, the investigators can calculate clinical measures of beta-cell function, including oral Disposition Index as well as the Homeostatic Model Assessment of beta-cell function (HOMA-B), and beta-cell glucose sensitivity. This hybrid approach, blending advanced digital data acquisition with traditional clinical assessments, will facilitate the identification of critical data patterns and biomarkers correlating with beta-cell function. The envisioned outcome is a scalable tool for early identification of individuals experiencing a decline in beta-cell function.

Inclusion Criteria:

• 18+ years old
• Have an established diagnosis of Prediabetes or Type 2 diabetes
• Have a glycated hemoglobin (HbA1c) below 8% (64 mmol/mol) and a body mass index (BMI) between 18-40 kg/m2 that will be determined from your height and weight
• Are willing to use an Abbott FreeStyle Libre 3/3+ Continuous Glucose Monitor (CGM) supplied by the study and provide the study investigators access to the CGM data
• Are willing to use the study wearable devices (e.g., Oura Ring)
• Are able to read, write, and speak in English
• If you use long-acting insulin, you must be on a prescribed regimen where you administer it at bedtime only and no other time of day (bolus short-acting may be used at any time as needed)
• All medication regimens must have a minimum of 30 days supply, and no new medications started within 30 days of enrollment
• Weight must be stable (± 10 pounds) for 2 months prior to enrollment
• Must have a personally owned iPhone 6s or newer (iOS 16.4+) or Android smartphone (version 12 or newer) and use this phone to download and use the study app and use the provided study devices
• Must have a personally owned computer or tablet or have access to these devices at home
• Must reside in the North San Francisco Bay area and be willing to travel to Novato, CA to attend two morning clinic assessments at the Buck Institute

Exclusion Criteria:

• Using any Abbott CGM (prescribed or OTC)
• BMI <18 kg/m2 or >40 kg/m2
• Dairy or soy allergy
• Currently pregnant or breastfeeding
• Diagnosed with Type 1 diabetes or MODY (Maturity-Onset Diabetes of the Young)
• Using an insulin pump
• Using any of the following medications: Glucocorticoids, Non-Selective Beta Blockers (e.g., propranolol), Thiazide Diuretics
• Currently using tobacco products (cigarettes, vapes, chew, dip, etc.)
• Hospitalized overnight for any reason in the last 3 months
• History of pancreatic disease (other than diabetes) or pancreatic transplantation
• Have any active malignancy within the last 12 months
• History of bariatric / other gastrointestinal surgery anticipated to affect glucose metabolism / cause gastroparesis
• History of systemic disease (hepatic, cardiovascular, other) likely to interfere with glucose metabolism or study participation

Individuals with prediabetes or Type 2 diabetes

Deidentified study data will be shared beyond the internal research team by 4YouandMe with external qualified researchers using an ARPA-H approved data sharing platforms such as the Synapse Data Sharing Platform at Sage Bionetworks. This data sharing will occur 1 year after the last participant has exited the study. Researchers from other institutions, and other third parties will be able to apply for access to the deidentified dataset by presenting a research study plan for analysis that has been reviewed by an IRB or ethics committee. Data released through these ARPA-H approved data sharing platforms will be stored indefinitely.