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The Metabolic Effects of Short-term Walnut Consumption in Subjects With the Metabolic Syndrome

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ClinicalTrials.gov Identifier: NCT00525629
Recruitment Status : Completed
First Posted : September 6, 2007
Results First Posted : February 23, 2017
Last Update Posted : December 15, 2017
Information provided by (Responsible Party):

Study Description
Brief Summary:

Walnuts include many potentially beneficial micronutrients and phytochemicals, in this study we propose to examine the effects of walnuts independent of macronutrient content. The purpose of this proposal is to study in depth the short-term effects of walnut consumption in men and women with the metabolic syndrome.

Study Aim 1: To investigate the effects of walnuts (48gms per day over 3 days) on insulin resistance in subjects with the metabolic syndrome.

Study Aim 2: To investigate the effects of 48gms per day of walnuts over 3 days on lipids and inflammatory markers.

Study Aim 3: To assess the possible mechanisms of the biological effects of short-term walnut consumption through assessment of adipokines, resting metabolic rate, gene expression in white blood cells and the effect of walnuts when consumed as part of a mixed meal, on glucose excursions, insulin secretion and the excretion of gut peptides and free fatty acids.

Condition or disease Intervention/treatment
Metabolic Syndrome Type 2 Diabetes Cardiovascular Disease Dietary Supplement: Walnuts Dietary Supplement: Control

  Show Detailed Description

Study Design

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 40 participants
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double (Participant, Investigator)
Primary Purpose: Basic Science
Official Title: The Metabolic Effects of Short-term Walnut Consumption in Subjects With the Metabolic Syndrome
Study Start Date : February 2007
Primary Completion Date : December 2008
Study Completion Date : December 2008

Arms and Interventions

Arm Intervention/treatment
Experimental: Walnut Diet
48 Grams of Walnuts Daily
Dietary Supplement: Walnuts
48 Grams of Walnuts Daily
Placebo Comparator: Control Diet
Isocaloric Diet with No Walnuts
Dietary Supplement: Control
Control Diet with No Walnuts

Outcome Measures

Primary Outcome Measures :
  1. Insulin Resistance [ Time Frame: 4 days ]
    HOMA-IR (homeostatic model assessment of insulin resistance) given in units as it is a ratio equation.

Eligibility Criteria

Information from the National Library of Medicine

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Ages Eligible for Study:   40 Years to 75 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Metabolic Syndrome is defined as follows:

Central Obesity- for Europid men this is a waist circumference of > 94cm for women >80cm or BMI >30.

Plus 2 of the following 4 factors

  1. Elevated triglycerides: > 150 mg/dL
  2. Reduced HDL cholesterol < 40 mg/dL in men and < 50 mg/dL in women.
  3. Raised diastolic blood pressure systolic BP > 130mmHg or diastolic BP > 85mmHg or treatment with antihypertensives.
  4. Raised fasting plasma glucose > 100mg/dL or previously diagnosed type II diabetes.

Exclusion Criteria:

  1. Subjects with diabetes requiring medication or insulin are excluded.
  2. Subjects with any medical condition or on any treatment, which would interfere with the study outcomes or would make participation potentially harmful such as pregnancy or breastfeeding, anemia, heart disease, stroke, malabsorption syndromes according to a detailed medical history.
  3. Present alcoholism or drug abuse or use of medications that could interfere with the study such as corticosteroids, growth hormone, antiretroviral therapy. These conditions will be screened for by a detailed history and systems review.
  4. Individuals with nut allergy are excluded.
Contacts and Locations

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 ClinicalTrials.gov identifier (NCT number): NCT00525629

United States, Massachusetts
Beth Israel Deaconess Medical Center
Boston, Massachusetts, United States, 02215
Sponsors and Collaborators
Christos Mantzoros
California Walnut Commission
Principal Investigator: Christos S Mantzoros, MD Beth Israel Deaconess Medical Center
More Information

Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: Christos Mantzoros, Principal Investigator, Beth Israel Deaconess Medical Center
ClinicalTrials.gov Identifier: NCT00525629     History of Changes
Other Study ID Numbers: 2006P000255
First Posted: September 6, 2007    Key Record Dates
Results First Posted: February 23, 2017
Last Update Posted: December 15, 2017
Last Verified: June 2017

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