Tart Cherry, Metabolic Syndrome, and Cardiovascular Risk

Tart Cherry Improves Cardiovascular Risk Factors Associated With Metabolic Syndrome

The hypothesis of this study is that the daily consumption of 480 ml tart cherry juice for twelve weeks will improve blood pressure and arterial stiffness by improving endothelial-mediated vasodilation and vascular sympathetic activity and favorably altering biochemical markers associated with cardiovascular risk. 28 men and women between the ages of 20 and 40 who have three of the five features of metabolic syndrome as defined by the Adult Treatment Panel III will be included in the study. After a two-week run-in phase, eligible men and women will be randomly assigned to one of two treatment groups: 1) 480 ml tart cherry juice or 2) 480 ml control drink daily for twelve weeks. After an initial telephone screening, all participants will be requested to report to the study site for their first visit. On the first visit (screening), participants will be provided with verbal and written explanation of the project. They will then be asked to sign an informed consent form, followed by measuring waist circumference, resting brachial blood pressure, fasting serum triglycerides, high density lipoprotein cholesterol, and glucose levels to confirm metabolic syndrome. Baseline assessments will be performed for medical history, medication use, dietary intake, and physical activity. Qualified participants will be scheduled for their second visit two weeks later (actual baseline data collection) and randomly assigned to their treatment group. On the second (baseline) visit between the hours of 7-10 A.M., blood pressure and vascular function will be measured followed by blood draw. Anthropometrics will be measured. Participants will be provided with their assigned treatment and will receive standard instructions on how to fill out daily diaries for their treatment, and for food and physical activity records. Blood pressure, vascular function, blood draw, and anthropometric, body composition, diet, and physical activity assessments will be repeated at 6- (third visit), and 12-week (final visit) intervals. All cardiovascular measurements will be performed between 7:00 to 10:00 A.M., in a quiet temperature-controlled room in the supine position after an overnight fast and 12 hours after the abstinence of caffeine and/or 24 hours after the last bout of moderate to heavy physical activity.

Study Overview

• Status: Completed
• Conditions: Cardiovascular Diseases; Diabetes; Metabolic Syndrome
• Intervention / Treatment: Dietary supplement: Tart Cherry; Dietary supplement: Placebo

• Study Type: Interventional
• Enrollment (Actual): 26
• Phase: Phase 2

Contacts and Locations

Study Locations

• United States
  • Florida
    • Tallahassee, Florida, United States, 32306
      • Department of Nutrition, Food and Exercise Sciences, Center for Advancing Exercise and Nutrition Research on Aging, Florida State University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 20 years to 60 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Three of the following five features at the screening visit:
• Waist circumference of ≥ 40 inches for men and 35 inches for women
• Serum triglycerides ≥ 150 mg/dL
• Serum high density lipoprotein cholesterol levels < 40 mg/dL for men and <50 mg/dL for women
• Blood pressure ≥ 130/85 mm Hg
• Fasting blood glucose level ≥ 110 mg/dL

Exclusion Criteria:

• Taking hypoglycemic, antihypertensive or cholesterol-lowering medications
• Diagnosed cardiovascular disease
• Uncontrolled hypertension (≥ 160/100 mmHg)
• Diabetes mellitus
• Other active chronic diseases such as cancer, asthma, glaucoma, thyroid, kidney, liver and pancreatic disease
• Participating in a weight loss program
• Heavy smokers (> 20 cigarettes per day)
• Heavy drinkers (> 12 alcoholic drinks per week)
• Abnormal menstrual cycle

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Tart Cherry; 12 weeks of tart cherry juice taken in two doses of 240 ml per day.	Dietary supplement: Tart Cherry; 12 weeks of tart cherry juice taken in two doses of 240 ml per day.
Placebo Comparator: Placebo; 12 weeks tart cherry juice taken in two doses of 240 ml per day.	Dietary supplement: Placebo; 12 weeks of tart cherry juice taken in two doses of 240 ml per day.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Blood Pressure	By measuring brachial and aortic blood pressure at rest and during physiological stress (handgrip exercise and post-exercise muscle ischemia).	12 weeks
Arterial Stiffness	By measuring arterial stiffness and augmentation index at rest and during physiological stress (handgrip exercise and post-exercise muscle ischemia).	12 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Oxidative Stress	By measuring markers of oxidative stress.	12 weeks
Body Composition	By measuring fat mass and fat-free mass using dual-energy X-ray absorptiometry and anthropometrics.	12 weeks
Autonomic Control of Blood Pressure	By measuring blood pressure variability and baroreflex sensitivity at rest and during physiological stress.	12 weeks
Endothelial-mediated Vasodilation	By measuring flow-mediated dilation in the brachial artery.	12 weeks
Atherogenic Markers	By measuring adhesion factors, lipid profiles, and atherogenic risk ratios.	12 weeks
Endothelial Function	By measuring markers of endothelial function.	12 weeks
Inflammation	By measuring a marker of inflammation.	12 weeks
Insulin Sensitivity	By measuring fasting glucose, insulin, and homeostatic model assessments of insulin resistance, sensitivity, and beta cell function.	12 weeks

Collaborators and Investigators

• Sponsor: Florida State University
• Collaborators: Cherry Research Committee
• Investigators: Principal Investigator: Sarah A. Johnson, PhD, RDN, Department of Food Science and Human Nutrition, Colorado State University; Principal Investigator: Bahram H. Arjmandi, PhD, RD, Department of Nutrition, Food and Exercise Sciences, Center for Advancing Exercise and Nutrition Research on Aging, Florida State University; Principal Investigator: Arturo Figueroa, MD, PhD, Department of Nutrition, Food and Exercise Sciences, Florida State University

Study record dates

Study Major Dates

• Study Start: April 1, 2014
• Primary Completion (Actual): October 1, 2016
• Study Completion (Actual): October 1, 2016

Study Registration Dates

• First Submitted: May 30, 2014
• First Submitted That Met QC Criteria: May 30, 2014
• First Posted (Estimate): June 3, 2014

Study Record Updates

• Last Update Posted (Estimate): December 8, 2016
• Last Update Submitted That Met QC Criteria: December 6, 2016
• Last Verified: December 1, 2016

More Information

Terms related to this study

• Keywords: Endothelial Function; Metabolic Syndrome; Arterial Stiffness; Blood Pressure; Tart Cherries
• Additional Relevant MeSH Terms: Pathologic Processes; Glucose Metabolism Disorders; Metabolic Diseases; Disease; Insulin Resistance; Hyperinsulinism; Cardiovascular Diseases; Syndrome; Metabolic Syndrome
• Other Study ID Numbers: RF02406