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Cocoa and Endothelial Function in Adults With Elevated BMI (Chocolate)

This study has been completed.
Centers for Disease Control and Prevention
The Hershey Company
Information provided by:
Griffin Hospital Identifier:
First received: September 28, 2007
Last updated: NA
Last verified: September 2007
History: No changes posted

Cardiovascular disease is the leading cause of death in the United States. Studies have shown that obesity is an important risk factor for development of cardiovascular disease. Endothelial dysfunction, a pathologic feature of obesity, predicts the occurrence of cardiovascular disease. Recent research findings indicate that consumption of cocoa exerts cardioprotective effects, which include increasing HDL levels, reduction in systolic BP, inhibition of platelet aggregation/activity and activation of endothelial nitric oxide synthase.

Proposed is a randomized controlled trial consisting of 4 phases designed to examine the dose-response, and the acute and sustained effects of cocoa consumption on endothelial function as a marker of cardiovascular disease risk in 45 otherwise healthy adults with a BMI 25-35kg/m2.

Condition Intervention Phase
Cardioprotection Other: Chocolate Phase 1

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single (Investigator)
Primary Purpose: Prevention
Official Title: Dark Chocolate and Cocoa Ingestion and Endothelial Function: A Randomized, Placebo Controlled, Cross-Over Trial

Further study details as provided by Griffin Hospital:

Primary Outcome Measures:
  • Endothelial Function(acute & sustained phase) [ Time Frame: Single dose(acute phase), 6 weeks (sustained phase) ]

Secondary Outcome Measures:
  • Blood Pressure(acute and sustained phase), lipid profile(sustained), LDL oxidation(sustained), lipid hydroperoxide(sustained), CRP(sustained), blood glucose(sustained), body weight(sustained), waist circumference(sustained), endothelin(sustained) [ Time Frame: Single dose(acute phase), 6 weeks(sustained phase) ]

Enrollment: 45
Study Start Date: August 2005
Study Completion Date: May 2006
Arms Assigned Interventions
Experimental: 1, 2
acute phase, solid dark chocolate, placebo
Other: Chocolate
74 grams of single dose solid dark chocolate versus placebo
Experimental: 3, 4, 5
acute phase, sugared cocoa, sugar-free cocoa, placebo
Other: Chocolate
22 grams of single dose sugared cocoa, sugar-free cocoa, and placebo
Experimental: 6, 7, 8
sustained phase, sugared cocoa, sugar-free cocoa, placebo
Other: Chocolate
22 grams of sugared cocoa, sugar-free cocoa, & placebo given for six weeks

Detailed Description:

Endothelial function has been used extensively to evaluate the acute and chronic effects of foods and nutrients on cardiac risk and can provide a direct measurement of the effect of cocoa powder consumption on vascular physiology in healthy adults with BMI between 25-35 kg/m2.

To our knowledge, our study is the first to examine the dose response effects of sugar free, liquid, cocoa and solid, dark chocolate with sugar consumption on FMD, concentrating on individuals with elevated BMI. Given the current epidemic of obesity in the United States; its role as a risk factor in the development of cardiovascular disease; and the fact that cardiovascular disease is the leading cause of mortality in this country, examination of the cardio-protective effects of cocoa or dark chocolate in an at risk population is of considerable potential interest. Demonstrating that ingestion of cocoa may reverse damage caused to the endothelium may lead to new dietary recommendations that may help curb the prevalence of heart disease in the U.S.


Ages Eligible for Study:   30 Years to 75 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Ages between 30 -75
  • BMI between 25-35 kg/m2
  • waist circumference above 88 cms. in women and 102 cms. in men
  • non-smoker
  • no strenuous exercise at least 8 hours prior to scanning
  • to facilitate recruitment individuals with diagnosed hypertension or hyperlipidemia will be included provided that they have been stable on their medications for three months, and can refrain from taking their medication 12 hours prior to BARS testing.

Exclusion Criteria:

  • Failure to meet inclusion criteria
  • anticipated inability to complete study protocol for any reason
  • current eating disorder
  • diagnosed coronary artery disease
  • diabetes
  • sleep apnea
  • current or impending pregnancy
  • insulin or glucose sensitizing medication use, vasoactive medication or nutriceutical use (glucocorticoids, antineoplastic agents, psychoactive agents, or bronchodilators)
  • regular use of high dose vitamin E or C and unable to discontinue for duration of the study
  • regular use of fiber supplements and unable to discontinue for duration of the study
  • restricted diets by choice (i.e. vegan, Atkins diet etc)
  • allergy to cocoa or chocolate.
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT00538083

United States, Connecticut
Griffin Hospital
Derby, Connecticut, United States, 06418
Sponsors and Collaborators
Griffin Hospital
Centers for Disease Control and Prevention
The Hershey Company
Principal Investigator: David L Katz, MD Yale-Griffin Prevention Research Center
Study Director: Zubaida Faridi, MPH Yale-Griffin Prevention Research Center
  More Information Identifier: NCT00538083     History of Changes
Other Study ID Numbers: Griffin Hospital IRB 2005-12
Study First Received: September 28, 2007
Last Updated: September 28, 2007

Keywords provided by Griffin Hospital:
Overweight adults
Endothelial function
Blood pressure
Cardiovascular disease risk
Dark chocolate
Sugar processed this record on September 21, 2017