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Flavonoid Effect on Activation and Stimulation of Thrombocytes, hsCRP and Lipid Profile (FEAST-CAL)

This study has been completed.
Information provided by:
LifeBridge Health Identifier:
First received: November 15, 2007
Last updated: November 16, 2007
Last verified: November 2007

The purpose of this study is to compare the effect of dark chocolate with green tea in healthy subjects on clot formation (platelet activity) cholesterol profile and markers of inflammation in two groups.

The first group will be on a regimen of dark chocolate, and the second group will be on a regimen of green tea. Clinical outcomes will be determined after seven days of each treatment and both groups will undergo both treatments subsequently and serve as their own control.

The hypothesis is that both green tea and dark chocolate will reduce platelet activity and reduce LDL, hsCRP and increase HDL.

Condition Intervention
Dietary Supplement: Green tea
Dietary Supplement: 70% dark chocolate

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Open Label
Primary Purpose: Treatment
Official Title: Flavonoid Effect on Activation and Stimulation of Thrombocytes, hsCRP and Lipid Profile

Further study details as provided by LifeBridge Health:

Primary Outcome Measures:
  • The primary outcome was the absolute change in platelet activity measured by Flow Cytometry, HDL, LDL and hsCRP after dark chocolate, respective green tea treatment. [ Time Frame: one week of dark chocolate versus one week of green tea ingestion ]

Enrollment: 35
Study Start Date: September 2006
Study Completion Date: April 2007
Arms Assigned Interventions
Active Comparator: GT
The green tea group is given initially green tea treatment and then after a washout period of four weeks switched to the dark chocolate treatment.
Dietary Supplement: Green tea

The green tea group consumed first daily one liter of green tea infusate made of 4 bags left in boiling water during 3 minutes.

After a four week washout-time they were switched over to the dark chocolate treatment, which included consumption of 3.5 ounces 70% dark chocolate.

Blood was drawn before and after each intervention, to check platelet activity with flow cytometry, HDL, LDL and hsCRP Levels

Active Comparator: DC
The dark chocolate group is given initially dark chocolate treatment and then after a washout period of four weeks switched to the green tea treatment.
Dietary Supplement: 70% dark chocolate

The dark chocolate group consumed 3.5 ounces 70% dark chocolate per day during a one week period.

After a four week washout-time they were given the green tea treatment, which included ingestion of one liter green tea infusate (containing 4 green tea bags).

Blood was drawn before and after each intervention, to check platelet activity with flow cytometry, HDL, LDL and hsCRP Levels.

Detailed Description:

Flavonoids are polyphenolic compounds ubiquitous in fruits and vegetables. They appear in especially high concentrations in the form of flavanols in green tea as well as in cocoa, and are known to have beneficial antioxidant effects in vitro. Flavonoids have been proposed as a key protective dietary component, reducing the risk of coronary heart disease, including the reduction of elevated blood pressure in persons with hypertension and capable of decreasing LDL.

The aim of this prospective single cross-over study is to assess the effect of green tea and dark chocolate consumption on inhibiting platelet activation, Lipid levels, and hsCRP in healthy volunteers.

This research will be done at Sinai Hospital of Baltimore and will include 35 subjects who will be randomized equally between the two groups.

All blood work will be processed at the Sinai Center for Thrombosis Research. Clinical outcomes will be recorded using a standard case report form.


Ages Eligible for Study:   18 Years to 55 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • non-smokers between the ages of 18-60
  • BMI of 19 to 30

Exclusion Criteria:

  • prior usage of Vitamin C > 1000 mg, Vitamin E > 400IU, Beta Carotene > 1000IU, Vitamin A > 5000IU, Selenium > 200mcg, Folic Acid > 1mg, Aspirin or NSAIDs four weeks prior to study initiation
  • regular ingestion of Flavonoid rich food (EG green tea, dark chocolate, grapes, red wine and others) prior and during the study except what was provided by the study protocol
  • Alcohol or Caffeine consumption 24 prior to blood draws
  • Nursing or pregnant women
  • blood donation up to eight weeks prior to study initiation
  • subjects with coagulation disorders
  • known cardiovascular disease (prior myocardial infarction)
  • drug abuse
  • Diabetes
  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: NCT00559663

United States, Maryland
Center for Thrombosis Research, Sinai Hospital
Baltimore, Maryland, United States, 21215
Sponsors and Collaborators
LifeBridge Health
Principal Investigator: Paul A Gurbel, MD Sinai Hospital of Baltimore
Study Director: Miruais S Hamed, MD Department of Medicine, Sinai Hospital, Baltimore
Study Chair: Kevin Bliden, BS Sinai Center for Thrombosis Research
  More Information Identifier: NCT00559663     History of Changes
Other Study ID Numbers: 1242
Study First Received: November 15, 2007
Last Updated: November 16, 2007

Keywords provided by LifeBridge Health:
platelet reactivity processed this record on May 23, 2017