Mediterranean Diet and the Metabolic Syndrome (MedDiet)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00988650
Recruitment Status : Completed
First Posted : October 2, 2009
Last Update Posted : March 5, 2013
Canadian Institutes of Health Research (CIHR)
Information provided by (Responsible Party):
Benoit Lamarche, Laval University

Brief Summary:

While there is now undisputable evidence relating elevated plasma low-density lipoprotein (LDL) cholesterol levels to an increased risk of coronary heart disease (CHD), it is being increasingly recognized that a significant proportion of CHD events occur in individuals characterized by a cluster of additional metabolic and physiological perturbations now defined as the metabolic syndrome. Epidemiological and clinical evidence have shown us that nutritional factors, often in conjunction with obesity, play a pivotal role in the pathophysiology of the metabolic syndrome. In that regard, accumulating evidence suggest that a Mediterranean-style diet (MedDiet) may beneficially modify several components of the metabolic syndrome including plasma triglycerides (TG) and high-density lipoprotein (HDL) cholesterol levels, insulin resistance, waist circumference and markers of vascular inflammation. However, the physiological mechanisms underlying the cardioprotective effects of the MedDiet on features of the metabolic syndrome and the importance of body weight reduction in maximizing these effects represent key issues that have yet to be investigated.

The general objective of the study is to investigate for the first time in a controlled feeding study the mechanisms and factors underlying the impact of the MedDiet, with and without weight loss on the dyslipidemic features of the metabolic syndrome.

Condition or disease Intervention/treatment Phase
Cardiovascular Disease Other: isocaloric diet Other: free living conditions Not Applicable

Detailed Description:
The study has a duration of 35 weeks for each participant. Subjects will be first assigned to a North American control diet that they will consume for five weeks under isocaloric, weight-maintaining conditions. Participants will then consume the MedDiet for 5 weeks, again under isocaloric, weight-maintaining conditions. All foods will be provided to participants during these consecutive 5-week diets. Participants subsequently will then undergo a 20-week weight loss period in free-living conditions during which they will be given advice on how to create a 500 kcal deficit in their daily energy intake. The last phase of the study consists of a second 5-week MedDiet consumed under feeding, weight stabilizing conditions. Metabolic studies and CHD risk factor assessment will be performed at the end of each experimental diets. Metabolic studies include the measurement of in vivo kinetics of apolipoprotein (apo)B-containing lipoproteins including small dense LDL, apoCIII, HDL (apoAI) and C-reactive protein (CRP) as well as indirect measures of cholesterol absorption and synthesis.

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 26 participants
Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Prevention
Official Title: Mechanistic Investigation of the Mediterranean Diet and Its Impact on the Metabolic Syndrome in Men
Study Start Date : May 2007
Actual Primary Completion Date : December 2008
Actual Study Completion Date : December 2008

Resource links provided by the National Library of Medicine

Arm Intervention/treatment
Active Comparator: North American diet
Control North American diet for five weeks in isocaloric conditions
Other: isocaloric diet
Other Name: 3 isocaloric die

Experimental: Mediterranean diet
Mediterranean diet for five weeks in isocaloric conditions
Other: isocaloric diet
Other Name: 3 isocaloric die

Experimental: weight loss period
Weight loss period of 20-week (minimum 5% reduction in body weight)
Other: free living conditions
Other Name: weight lost free living conditions

Active Comparator: Weight stabilizing mediterranean diet
Mediterranean diet for five weeks in isocaloric weight stabilizing conditions
Other: isocaloric diet
Other Name: 3 isocaloric die

Primary Outcome Measures :
  1. plasma LDL, TG and HDL-C [ Time Frame: Week 5, 10 and 35 (at the end of each weight-maintaining diet) ]

Secondary Outcome Measures :
  1. CRP, and blood pressure, kinetic of lipoproteins [ Time Frame: Week 5, 10 and 35 (at the end of each weight-maintaining diet) ]

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years to 65 Years   (Adult, Older Adult)
Sexes Eligible for Study:   Male
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Men from the Québec City metropolitan area with the metabolic syndrome based on the NCEP-ATP III definition (3 criteria or more see below):
  • Waist circumference ≥ 102 cm
  • Triglycerides ≥ 1.7 mmol/L
  • HDL-cholesterol <= 1.04 mmol/L
  • Systolic blood pressure ≥ 130 mmHg or diastolic blood pressure ≥ 85 mmHg
  • Fasting blood glucose ≥ 5.6 mmol/L
  • Stable body weight (+/- 2 kg) for 6 months before the beginning of the study

Exclusion Criteria:

  • Previous history of cardiovascular disease, type 2 diabetes and monogenic dyslipidemia
  • Subjects taking medications for hyperlipidemia or hypertension
  • Endocrine disorders
  • Food allergies or aversion for specific components of the MedDiet
  • Smokers
  • Consummation excessive of alcohol (> 2 consummation/day)

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00988650

Institute of Nutraceutical and Functional Foods (INAF), Laval University
Quebec, Canada, G1V 0A6
Sponsors and Collaborators
Laval University
Canadian Institutes of Health Research (CIHR)
Study Director: Benoît Lamarche, PhD Institute of Nutraceutical and Functional Foods (INAF), Laval University

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: Benoit Lamarche, Professor, Laval University Identifier: NCT00988650     History of Changes
Other Study ID Numbers: INAF-2006-277
First Posted: October 2, 2009    Key Record Dates
Last Update Posted: March 5, 2013
Last Verified: March 2013

Keywords provided by Benoit Lamarche, Laval University:
Metabolic syndrome
Mediterranean diet
Blood lipids
Coronary heart disease

Additional relevant MeSH terms:
Cardiovascular Diseases
Metabolic Syndrome X
Insulin Resistance
Glucose Metabolism Disorders
Metabolic Diseases