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

Not Applicable

Completed

Conditions: Dietary Habits

Interventions: Other: Low-Carb High-Fat breakfast
Other: Low fat "standard care" control breakfast

Registration Number: NCT04550468

Lead Sponsor: University of British Columbia

Brief Summary: 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.

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.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 127

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 & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Low-Carb High-Fat Breakfast	Low-Carb High-Fat breakfast	Participants will follow a daily low carbohydrate high fat breakfast intervention for 3 months.
Low fat "Standard Care" Control Breakfast	Low fat "standard care" control breakfast	Participants will follow a daily low fat "standard care" control breakfast intervention for 3 months.

Primary Outcome Measures

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

Secondary Outcome Measures

Name	Time	Method
Change From Baseline Fasting Blood Glucose at 12 Weeks	Mean values for the first 14 days (weeks 1-2) and mean values for the last 14 days (weeks 11-12) of the intervention	Mean fasting blood glucose from 14 days measured at baseline and after 12 weeks of following the low-carbohydrate breakfast or low-fat breakfast
Change From Baseline Fasting Blood Insulin at 12 Weeks	Baseline to 12 weeks of diet	Average fasting blood insulin measured at baseline and after 12 weeks of following the low-carbohydrate breakfast or low-fat breakfast
Change From Baseline Blood Lipids at 12 Weeks	Baseline to 12 weeks of diet	Mean triglycerides, total, HDL, and LDL cholesterol at baseline and after 12 weeks of following the low-carbohydrate breakfast or low-fat breakfas
Change From Baseline Inflammation Marker High Sensitive Reactive Protein (hsCRP) at 12 Weeks	Baseline to 12 weeks of diet	Blood inflammation marker (hsCRP) at baseline and after 12 weeks of following the low-carbohydrate breakfast or low-fat breakfast
Hunger/Satiety Levels	Weeks 1, 6 and 12	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?
Dietary Intake	Mean dietary intake assessed during the 12-week intervention	Dietary calorie intake assessed by three 3-day food records during the 12-week intervention
Change From Baseline Body Weight at 12 Weeks	Baseline to 12 weeks of diet	Body weight measured in kilograms at baseline and after 12 weeks of following the low-carbohydrate breakfast or low-fat breakfast
Change From Baseline Body Mass Index at 12 Weeks	Baseline to 12 weeks of diet	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
Continuous Glucose Monitoring	Mean values for the first 14 days (weeks 1-2) and mean values for the last 14 days (weeks 11-12) of treatment	Measures of overall glucose control by continuous glucose monitoring device