This trial is active, not recruiting.

Conditions type 2 diabetes, obesity, overweight, cardiovascular diseases
Treatments a canola oil enriched mediterranean diet, a high wheat fiber diet
Sponsor St. Michael's Hospital, Toronto
Collaborator University of Toronto
Start date October 2014
End date October 2019
Trial size 164 participants
Trial identifier NCT02245399, CFC/Fund 200134/496744, REB# 14-086


The purpose of the study is to assess whether a Mediterranean-type weight-loss diet, enriched with canola oil, high in plant protein, and low in carbohydrates will produce blood sugar control, reduce coronary heart disease (CHD) risk factors and maximize weight loss, better than conventional higher carbohydrate diets in overweight diabetic patients.

United States No locations recruiting
Other countries No locations recruiting

Study Design

Allocation randomized
Endpoint classification efficacy study
Intervention model parallel assignment
Masking single blind (investigator)
Primary purpose treatment
Participants will be advised to consume, a low-carbohydrate diet (26-32% of calories), high in vegetable protein (28-32%) and fat (41-45%) with canola as the major component (10%). Carbohydrate sources will feature viscous fiber-containing foods (including psyllium cereal, oats and barley) and low-starch vegetables (emphasizing okra and eggplant) for the relatively limited amount of carbohydrate.
a canola oil enriched mediterranean diet A mediterranean weight-reducing diet emphasizing canola oil
The diet will be provided at 60% of calories estimated for stable body weight to encourage weight loss. A high protein canola oil-enriched test bread will be provided as a supplement.
(Active Comparator)
Participant will be advised to consume a high carbohydrate diet (58% carbohydrate, 16% protein and 25% fat) emphasizing whole wheat/whole grain cereals and increased high fiber alternatives, with fruits and vegetables.
a high wheat fiber diet DASH-type diet
The diet will be provided at 60% of calories estimated for stable body weight to encourage weight loss. A whole wheat control bread will be provided as a supplement to participants

Primary Outcomes

change in HbA1c
time frame: Measured at weeks -2, 0, and then at weeks 8, 10 and 12

Secondary Outcomes

Change in body weight
time frame: baseline (week 0) and end (week 12)
blood glucose
time frame: At weeks 0, 2, 4, 8, 10 and 12
Serum lipids: total cholesterol, LDL-chol, HDL-chol and Triglycerides
time frame: At weeks 0, 4, 8, 10 and 12
Blood pressure
time frame: At weeks 0, 4, 8, 10 and 12
24-hour Ambulatory blood pressure profile
time frame: At weeks -1 and 12
diet history
time frame: At weeks 0, 2, 4, 8, 10 and 12
C-reactive protein
time frame: At weeks 0 and 12
Cholesterol absorption
time frame: At weeks -1 and 12
change in LDL particle size
time frame: Weeks 0 and 12
urinary analyses
time frame: week 0 and week 12

Eligibility Criteria

Male or female participants at least 21 years old.

Inclusion Criteria: - Men and women with type 2 diabetes diagnosed for more than 6 months - BMI >27 (non-Asians); BMI >25 (Asians) - HbA1c between 6.5% and 8.5% at screening, and at the preparation visit before starting diet - on a stable prescribed dose of oral diabetes medication for at least 2 months - on a stable dose of lipid medication for at least 2 weeks, if prescribed - on a stable dose of blood pressure medication for at least 1 week, if prescribed - have a family physician - can keep written food records, with the use of a digital scale Exclusion Criteria: Individuals with the following characteristics/conditions will be excluded - on insulin - on steroids - on warfarin (Coumadin) - GI disease (gastroparesis, celiac, colitis, Crohn's disease, Inflammatory Bowel Syndrome) - history of cancer, except non-melanoma skin cancer (basal cell, squamous cell) - major cardiovascular event (stroke, myocardial infarction) in past 6 months - major surgery in past 6 months - major debilitating disorder - liver disease (AST or ALT> 3x the upper limit of normal) except non-alcoholic fatty liver (NAFL) disease or non-alcoholic steatohepatitis (NASH). - hepatitis B or C - renal failure (creatinine > 150 mmol/L) - serum triglycerides >4.5mmol/L - acute or chronic infections (bacterial or viral) - chronic inflammatory diseases (e.g. lupus, ulcerative colitis) - blood pressure >145/90, unless approved by their family physician - alcohol consumption >2 drinks/d - food allergies to wheat, canola, or other study food components - any condition determined by the investigators to make the subject unsuitable for the study

Additional Information

Official title Canola Enriched Mediterranean Type Weight Loss Diet in Type 2 Diabetes
Principal investigator David J Jenkins, MD
Description The investigators plan to assess the effects of increasing both canola oil and plant protein foods while reducing carbohydrate intake in the context of a Mediterranean type diet on weight loss, glycemic control and cardiovascular risk factors in type 2 diabetes. Obesity rates in Western nations have shown a dramatic rise in the last 20 years and diabetes rates have doubled, a trend which is predicted to be repeated over the next 20 years. In Canada the predicted cost to the healthcare system in only 7 years will rise to $17 billion. Weight loss diets (such as Atkins, Eddies, South Beach and Zone) emphasizing carbohydrate restriction have become increasingly popular for the prevention and treatment of diabetes. As a result, lower carbohydrate diets are being selected by health conscious members of the general population including those with diabetes. Because such diets in effect promote a high intake of protein from animal sources, even in the presence of weight loss, serum cholesterol levels rise due to increased cholesterol and saturated fat intake; and a further rise in serum lipids is likely to occur in the long term when weight loss has ceased. On the other hand, lower carbohydrate dietary patterns that are higher in plant rather than animal fat and proteins have been associated with improved blood lipids and reduced risk of heart disease and type 2 diabetes. The investigators have therefore planned a study in which a weight reducing low carbohydrate, Mediterranean type diet that is high in plant proteins and canola oil will be compared to a weight reducing high cereal fibre diet in a 3 month study. 150 overweight and obese participants with type 2 diabetes will be randomized to one of 2 treatments. Study visits will be as follows: weeks -2, 0 (for randomization), 2, 4, 8, 10 and 12. Body measurements, blood pressure and blood samples will be taken at each visit except week 2. The week 2 visit will be mainly for reinforcement of dietary advice; also body weight will be measured and blood drawn for fast glucose and HbA1c. Diet records will be reviewed at all visits. 24 hour urine samples will be collected at week 0 and week 12. On completion of the 12 week study, participants will be given the option of continuing on the same diet or trying the opposite diet for a further 12 weeks. Visits will be every 4 weeks for a total of 3 visit. Body measurements, blood pressure and blood samples will be taken during these visits as in the initial 12 week study.
Trial information was received from ClinicalTrials.gov and was last updated in October 2016.
Information provided to ClinicalTrials.gov by St. Michael's Hospital, Toronto.