Effects of Canola Oil on Vascular and Metabolic Parameters in Individuals With Metabolic Syndrome

MetS is an early stage of CVD and is an appropriate target for dietary interventions. MetS is a clustering of risk factors (abdominal obesity, elevated serum triglycerides, low HDL-cholesterol, hypertension, elevated fasting blood glucose) accompanied by low grade chronic inflammation, hepatic steatosis (fatty liver) and reduced vascular function.

This study will investigate the effect of a 12 week intervention with canola oil versus the typical fat mixture in the Western diet on blood lipids, blood vessel function and MetS parameters. CVD risk will be assessed based on the profile of lipids and other factors in the blood as well using specialized equipment for non-invasive monitoring of blood vessel function.

The current, worldwide obesity epidemic is significantly increasing the number of individuals with Metabolic Syndrome (MetS), an early stage combination of risk factors which predisposes individuals to cardiovascular disease (CVD) and other chronic diseases. While it has been shown that modification of dietary fat intake can play an important role in prevention and management of CVD there is an absence of dietary intervention studies focusing on dietary oils and early stage modification of MetS components, particularly those affecting progression to CVD.

The composition of canola oil is considered healthy. However, there is a lack of scientifically sound clinical studies directly comparing canola oil with other fats in the diet. Given that much of the evidence for current dietary recommendations for type and amounts of fatty acids is based on heart disease, the proposed research will contribute to the knowledge base for dietary fat recommendations for individuals with MetS.

Specifically, this study will investigate the effect of a 12 week intervention with canola oil versus the typical fat mixture in the Western diet on blood lipids, blood vessel function and MetS parameters. CVD risk will be assessed based on the profile of lipids and other factors in the blood as well using specialized equipment for non-invasive monitoring of blood vessel function.

Eligibility Criteria:
Inclusion Criteria:

1. Male, or non-pregnant, non-lactating females, aged 20 - 75 years;
2. LDL-Cholesterol \>2.5 mmol/L and \<5.0 mmol/L
3. If the participant has 2 or more of the following characteristics of MetS

   * Fasting blood glucose \>5.6 mmol/L and \<7.0 mmol/L;
   * Blood pressure \>130/85 mm Hg and \<150/100;
   * Triglycerides \>1.7 mmol/L and \<4.0 mmol/L;
   * HDL-cholesterol \<1.0 mmol/L in males or \<1.3 mmol/L in females;
   * Abdominal obesity as defined by a waist circumference of \>102 cm (40 inches) in males and \>88 cm (35 inches) in females of non-Asian ethnicity, and a waist circumference of \>94 cm (37 inches) in males and \>80 cm (32 inches) in females of Asian ethnicity.
4. Able to read, write and communicate orally in English;
5. Willing to maintain a stable level of activity during participation in the study;
6. Willing to maintain dietary routine, refrain from consuming omega-3 supplements or omega-3 rich foods (\>0.3 grams ALA/serving or, \>0.1 grams of EPA and DHA; see handout with examples) and refrain from taking any over-the-counter medications or herbal supplements specified for weight loss, or the lowering of blood lipids, blood glucose or blood pressure from acceptance into the study until the final study visit;
7. Willing to comply with protocol requirements and procedures;
8. Willing to provide written informed consent.

Exclusion Criteria:

1. Use of prescribed medications for lowering or managing blood lipids (hyperlipidemia), blood glucose (hyper/hypoglycemia), blood pressure (hypertension) or body weight;
2. Regular use of non-prescription products, over-the-counter medications, or herbal supplements designed to lower blood lipids, blood glucose, blood pressure or body weight, or omega-3 supplements or omega-3 rich foods, within the past 3 months;
3. Participating in or adhering to a weight loss diet or physical activity program designed to facilitate weight loss.
4. Adhering to a physician or dietitian directed lifestyle or dietary modification program for the purpose of lowering hypercholesterolemia;
5. Medical history of liver disease, with the exception of fatty liver, or chronic renal disease;

5. Any acute medical condition or surgical intervention within the past 3 months; 6. Conditions or medications which are likely to increase the risk to the participants or study personnel, or to reduce the ability of the participant to comply with the protocol, or affect the results; 7. History of gastrointestinal reactions or allergies to canola oil or to one or more ingredients in the study foods which significantly limits the number of study foods that can be consumed; and 8. Currently participating in or having participated in a food intervention study within the last 3 months.