The Breakfast Study

The Breakfast Study: A Small Steps, Low-literacy, Breakfast-focused Dietary Self-management Intervention for Adults With Poorly Controlled Type 2 Diabetes

The investigators will conduct an acceptability, feasibility, preliminary effectiveness trial of a 4-month, online, very low-carbohydrate breakfast-focused program in 120 adults with type 2 diabetes. The investigators will measure acceptability and feasibility, plus critical efficacy outcomes, such as changes in HbA1c, anti-hyperglycemic medications, glycemic variability, body weight, blood pressure, and lipids.

Study Overview

• Status: Completed
• Conditions: Type 2 Diabetes
• Intervention / Treatment: Behavioral: Breakfast

Detailed Description

More than 15% of U.S. adults with type 2 diabetes have poorly controlled blood gluocse, here defined as a glycated hemoglobin (HbA1c) level of 7.0% or higher. These adults have an elevated health risk of a variety of outcomes, including amputation and mortality from cardiovascular disease and from all causes. Nutrition- focused interventions can be effective for improving glycemic control, reducing anti-hyperglycemic medications, and reducing body weight, all of which are critical outcomes for adults with type 2 diabetes. However, typical nutrition-focused interventions can be burdensome, often requiring complex instructions and a complete overhaul of one's diet. Additionally, adults with poorly controlled type 2 diabetes are more likely to have low literacy levels, which can be a barrier for adherence to complex interventions. Therefore, an effective intervention for adults with poorly controlled diabetes who may have lower health literacy levels is necessary to reduce both HbA1c levels and anti-hyperglycemic medications. Carbohydrate intake has the strongest impact on post-prandial glycemia of any dietary factor, and a very low-carbohydrate diet-due to its ability to improve glycemic control-is now recommended by the American Diabetes Association (ADA) for the treatment of type 2 diabetes. The investigators hypothesize that some of the benefits of a very low-carbohydrate diet may be available to individuals who change only their breakfasts to be very low-carbohydrate, rather than modifying their entire diet.

Thus, the investigators will conduct an acceptability, feasibility, preliminary effectiveness trial of a 4-month, online, small- steps, low-literacy, very low-carbohydrate breakfast-focused program in 120 adults with poorly controlled type 2 diabetes. The investigators will measure acceptability and feasibility, plus critical efficacy outcomes, such as changes in HbA1c, anti-hyperglycemic medications, glycemic variability, body weight, blood pressure, and lipids.

The investigators will also test whether factors such as sex, health literacy level, and baseline insulin resistance significantly moderate the impact of the intervention on change in HbA1c and change in anti-hyperglycemic medications.

• Study Type: Interventional
• Enrollment (Actual): 119
• Phase: Phase 2; Phase 1

Contacts and Locations

Study Locations

• United States
  • Michigan
    • Ann Arbor, Michigan, United States, 48109
      • University of Michigan

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• HbA1c 7% or higher
• 18-80 years old
• The ability to understand verbal and written English
• Willingness to follow the prescribed diet
• Able to consent and follow directions
• Willingness to regularly check blood glucose levels as required

Exclusion Criteria:

• Inability to provide informed consent
• Pregnant, breastfeeding, or planning for either in the next 6 months or <6 months postpartum
• Low C-peptide and possible subsequent GAD 65 level that suggests type 1 diabetes, clinical factors that suggest type 1 diabetes (lean, lack of family history, and diabetic ketoacidosis in the past) or a previous diagnosis of type 1 diabetes or latent autoimmune diabetes
• Cancer, heart failure, or kidney failure
• Vegan
• Untreated mental health condition
• Currently following a very low-carbohydrate diet or breakfasts
• Thyroid levels out of range
• Alcoholism
• Previous bariatric surgery
• Difficulty chewing or swallowing
• Dependence on others for food preparation
• Currently enrolled in another investigative study that might conflict with this research

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Very low-carbohydrate breakfast; Materials will encourage eating a very low-carbohydrate breakfast (or first meal of the day), with no more than about 5-10 non-fiber (net) grams of carbohydrates each.	Behavioral: Breakfast; We will provide participants recipes and information to support this dietary change.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Intervention satisfaction	A 1-item measure about intervention satisfaction. We ask participants, "How would you rate your overall satisfaction with the program?" The item is rated from 1 = very dissatisfied to 6 = very satisfied, with higher scores reflecting greater satisfaction.	At 4 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in HbA1c	This will assess the change in the level reported for this outcome	0 to 4 months
Weekly dietary adherence	A 1-item measure about dietary adherence. We ask participants to reflect on the past week and rate whether they ate a low-carbohydrate breakfast. The item is rated from 1 = not at all to 7 = very much so, with higher scores reflecting greater adherence.	Weekly over 4 months
Change in diabetes treatment satisfaction	The Diabetes Treatment Satisfaction Questionnaire is an 8-item measure of satisfaction with current diabetes therapy over the past several weeks. Each item is rated on a 7-point scale. Six items form the Treatment Satisfaction scale, assessing overall satisfaction, perceived convenience and flexibility, understanding of diabetes, and willingness to recommend or continue the current regimen. Two additional items evaluate the perceived frequency of unacceptable hyperglycemia and hypoglycemia. The Treatment Satisfaction score is calculated from the six satisfaction items, with higher scores indicating greater satisfaction; the two frequency items are scored separately, with higher values reflecting more frequent high or low blood glucose levels.	0 to 4 months
Change in health-related quality of life	The Patient-Reported Outcomes Measurement Information System (PROMIS)-29 is a 29-item survey for assessing health-related quality of life across seven domains (Physical function, Anxiety, Depression, Fatigue, Sleep disturbance, Social roles, and Pain interference) plus Pain intensity. All domains are scored using T-scores (mean 50, SD 10), where higher scores indicate better function for functional domains (Physical Function, Social Roles) and worse symptoms for symptom domains (Anxiety, Depression, Fatigue, Sleep Disturbance, Pain Interference).	0 to 4 months
Change in anti-hyperglycemic medications	The Medication Effect Score (MES) quantifies the overall intensity of antiglycemic therapy, with higher scores indicating greater medication requirements. For each diabetes medication, the percentage of the maximum recommended daily dose is multiplied by an adjustment factor reflecting its expected hemoglobin A1c-lowering potency; these values are summed to yield the total MES. Scores range from 0 upward (no fixed maximum), with lower scores reflecting lower medication intensity.	0 to 4 months

Collaborators and Investigators

• Sponsor: University of Michigan

Study record dates

Study Major Dates

• Study Start (Actual): August 2, 2023
• Primary Completion (Actual): October 9, 2025
• Study Completion (Actual): October 17, 2025

Study Registration Dates

• First Submitted: July 17, 2023
• First Submitted That Met QC Criteria: August 2, 2023
• First Posted (Actual): August 14, 2023

Study Record Updates

• Last Update Posted (Actual): November 21, 2025
• Last Update Submitted That Met QC Criteria: November 17, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Keywords: Nutrition therapy; Very low carbohydrate diet
• Additional Relevant MeSH Terms: Endocrine System Diseases; Metabolic Diseases; Glucose Metabolism Disorders; Diabetes Mellitus; Nutritional and Metabolic Diseases; Diabetes Mellitus, Type 2; Food; Diet, Food, and Nutrition; Physiological Phenomena; Food and Beverages; Meals; Breakfast
• Other Study ID Numbers: HUM00225646

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No