Low-carbohydrate Versus Low-fat Breakfast in Type 2 Diabetes

Impact of a Low-carbohydrate Versus Low-fat Breakfast on Blood Glucose Control in Type 2 Diabetes

The prevalence of type 2 diabetes (T2D) is increasing worldwide, with ~380 M currently suffering from this chronic, debilitating disease. T2D is characterized by high blood glucose levels in the mornings and after meals. The largest hyperglycemic spike often occurs after breakfast. Targeting this meal may be a simple, feasible strategy to improve glycemic control and reduce risk for diabetes complications. It is hypothesized that consuming a low carbohydrate high fat (LCHF) breakfast for 3 months, when compared to a standard low-fat breakfast will improve blood glucose control, increase satiety and improve body composition in people with T2D. This information will test whether the simple dietary strategy of limiting carbohydrates at breakfast could help in managing T2D.

Study Overview

• Status: Completed
• Conditions: Dietary Habits
• Intervention / Treatment: Other: Low-Carb High-Fat breakfast; Other: Low fat "standard care" control breakfast

Detailed Description

A 3-month parallel-group randomized controlled trial will be conducted. Eligible participants will be randomized to either the Low-carb High-fat breakfast (LCHF, n=41) or a low-fat "standard care" control breakfast (CTL, n=41), to be consumed daily for a period of 3 months.

Due to COVID-19 pandemic, this study was adapted to be conducted remotely through video/telephone conference meetings between participants and study staff, along with mailing of study materials before and after the intervention for remote data collection.

Each group will be provided with a menu of 8 LCHF breakfasts or 8 CTL breakfasts from which to choose each morning. Breakfast options (designed by a registered dietitian) will be controlled in macronutrient content and calories (~400-500 kcal), but allow for personal preference and autonomy to promote adherence.

• Study Type: Interventional
• Enrollment (Actual): 127
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Canada
  • British Columbia
    • Kelowna, British Columbia, Canada, V1V 1V7
      • University of British Columbia

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 20 years to 79 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• physician-diagnosed T2D of ≥1 year;
• current HbA1c of < 8.5%;
• BMI: >25 kg/m2; (as of July 5, 2021, BMI cut off was expanded from 25-40 kg/m2 to higher than 25kg/m2 to facilitate recruitment)
• blood pressure of <160/99 mm Hg assessed according to guidelines;
• non-smoking;
• not on hormone replacement therapy, corticosteroids, or anti-inflammatory medications;
• 20-79 years old.

Exclusion Criteria:

• Use of exogenous insulin;
• taking more than 2 glucose lowering medications;
• ongoing medical treatment for diseases such as cancer, auto-immune or inflammatory disease, liver or kidney disorders;
• allergy, intolerance or aversion to eggs or any other dietary restrictions (e.g., vegan, breakfast skipping) that will prevent them from following the standardized study diets;
• being unable to follow remote guidance by internet or smartphone
• being unable to follow the controlled diet instructions;.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Low-Carb High-Fat Breakfast; Participants will follow a daily low carbohydrate high fat breakfast intervention for 3 months.	Other: Low-Carb High-Fat breakfast; Participants will receive 8 low-carb high-fat breakfast meal recipes to follow daily during 3 months.
Active Comparator: Low fat "Standard Care" Control Breakfast; Participants will follow a daily low fat "standard care" control breakfast intervention for 3 months.	Other: Low fat "standard care" control breakfast; Participants will receive 8 low-fat breakfast meal recipes to follow daily during 3 months.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change From Baseline Hemoglobin A1c at 12 Weeks	Hemoglobin A1c measured at baseline and after 12 weeks of following the low-carbohydrate breakfast or low-fat breakfast	Baseline to 12 weeks of diet

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change From Baseline Fasting Blood Glucose at 12 Weeks	Mean fasting blood glucose from 14 days measured at baseline and after 12 weeks of following the low-carbohydrate breakfast or low-fat breakfast	Mean values for the first 14 days (weeks 1-2) and mean values for the last 14 days (weeks 11-12) of the intervention
Change From Baseline Fasting Blood Insulin at 12 Weeks	Average fasting blood insulin measured at baseline and after 12 weeks of following the low-carbohydrate breakfast or low-fat breakfast	Baseline to 12 weeks of diet
Change From Baseline Blood Lipids at 12 Weeks	Mean triglycerides, total, HDL, and LDL cholesterol at baseline and after 12 weeks of following the low-carbohydrate breakfast or low-fat breakfas	Baseline to 12 weeks of diet
Change From Baseline Inflammation Marker High Sensitive Reactive Protein (hsCRP) at 12 Weeks	Blood inflammation marker (hsCRP) at baseline and after 12 weeks of following the low-carbohydrate breakfast or low-fat breakfast	Baseline to 12 weeks of diet
Hunger/Satiety Levels	Levels of hunger and satiety measured by a 0 to 100 millimeter visual analog scale [ranges across a continuum from none (0) to an extreme amount (100) of Hunger, Satiety, Fullness, Appetite] How hungry do you feel? How satisfied do you feel? How full do you feel? How much food do you think you can eat?	Weeks 1, 6 and 12
Dietary Intake	Dietary calorie intake assessed by three 3-day food records during the 12-week intervention	Mean dietary intake assessed during the 12-week intervention
Change From Baseline Body Weight at 12 Weeks	Body weight measured in kilograms at baseline and after 12 weeks of following the low-carbohydrate breakfast or low-fat breakfast	Baseline to 12 weeks of diet
Change From Baseline Body Mass Index at 12 Weeks	Body mass Index measured in weight in kilograms divided by the square of height in meters at baseline and after 12 weeks of following the low-carbohydrate breakfast or low-fat breakfast	Baseline to 12 weeks of diet
Continuous Glucose Monitoring	Measures of overall glucose control by continuous glucose monitoring device	Mean values for the first 14 days (weeks 1-2) and mean values for the last 14 days (weeks 11-12) of treatment

Collaborators and Investigators

• Sponsor: University of British Columbia
• Collaborators: University of Wollongong

Study record dates

Study Major Dates

• Study Start (Actual): October 1, 2020
• Primary Completion (Actual): June 30, 2022
• Study Completion (Actual): June 30, 2022

Study Registration Dates

• First Submitted: July 15, 2020
• First Submitted That Met QC Criteria: September 14, 2020
• First Posted (Actual): September 16, 2020

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: February 2, 2025
• Last Verified: February 1, 2025

More Information

Terms related to this study

• Other Study ID Numbers: H19-03179

Drug and device information, study documents

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