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Completed

NCT Number: NCT03587883

Daily Intake of Cocoa Flavanols and Arterial Stiffness in Humans

A randomized, double-masked and cross-over dietary intervention study to investigate the effects of diet supplementation with cocoa flavanols on arterial stiffness in healthy adult human subjects.

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Key information

Conditions

Age range

25 year–65 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Ragle Human Nutrition Research Center, Department of Nutrition at UC Davis

Davis, California, 95616, United States

About this study

Cocoa flavanols (CF) are plant-derived compounds commonly present in the human diet. Examples of flavanol-containing foods and beverages are apples, chocolate, tea, wine, berries, pomegranate and nuts. Flavanols encompass a group of different compounds, and the final profile of flavanols in foods will depend on multiple factors including plant origin, time of harvesting, storage, food processing, and cooking techniques. The term "cocoa flavanols" (CF) as used here refers to the particular profile of flavanols and procyanidins naturally found in cocoa beans, and CF mainly consist of the monomeric flavanol (-)-epicatechin and its oligomeric derivatives (procyanidins) containing up to 10 monomer subunits.

Accumulating data resulting from dietary intervention studies suggest that the intake of diets rich in flavanols can exert a beneficial cardiovascular health effect in humans. However, most of these investigations have been conducted with patients with diverse health complications (e.g. hypertension, diabetes and coronary heart disease) rather than healthy subjects. Thus, the interpretation of these data in the context of nutrition, primary prevention, and dietary recommendations is limited. In the current study, the investigators propose to investigate the effects of cocoa flavanol intake on arterial stiffness in a healthy population of adults. The investigators submit that this investigation will provide novel insights into the potential health benefits of dietary flavanols and procyanidins in the context of cardiovascular health in humans. The data resulting from this study will be key to the design of larger scale studies in this context, which are needed to comprehensively study the role of dietary flavanols and procyanidins with regard to potential dietary recommendations and public health.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • 25-65 years old
  • BMI 18.5 - 34.9 kg/m2
  • Weight ≥ 110 pounds
  • Previously consumed cocoa and peanut products, with no adverse reactions
  • Having completed physical exercise similar to 5 MET within the last 2 months without having any physical limitations [e.g. i) Brisk walking (at 4 mph); ii) Mowing lawn; iii) Bicycling-light effort (10 mph) and iv) Playing tennis-doubles.]

Exclusion criteria

  • Adults unable to consent
  • Individuals who are not yet adults (infants, children, teenagers)
  • Pregnant women
  • Prisoners
  • Non-English speaking*
  • BMI ≥ 35 kg/m2
  • More than 150 minutes of moderate-intensity aerobic activity or 75 minutes of vigorous-intensity aerobic activity weekly and more than two days a week of muscle strengthening activities that work all major muscle groups (CDC recommended physical activity guidelines for adults)
  • Allergies to nuts, cocoa and chocolate products
  • Active avoidance of coffee and caffeinated soft drinks
  • A history of cardiovascular disease, stroke, renal, hepatic, or thyroid disease
  • History of clinically significant depression, anxiety or other psychiatric condition
  • History of difficult blood draws
  • History of Raynaud's disease
  • Indications of substance or alcohol abuse within the last 3 years
  • Current use of herbal, plant or botanical supplements (multi-vitamin/mineral supplements are allowed)
  • Blood Pressure >140/90 mm Hg
  • Blood Pressure < 100/60 mm Hg, or heart rate < 50 bpm (due to limitations in the assessment of arterial stiffness
  • GI tract disorders, previous GI surgery (except appendectomy)
  • Self-reported malabsorption (e.g. difficulty digesting or absorbing nutrients from food, potentially leading to bloating, cramping or gas)
  • Diarrhea within the last month, or antibiotic intake within the last month
  • Vegetarian, Vegan, food faddists, individuals using non-traditional diets, on a weight loss diet or individuals following diets with significant deviations from the average diet
  • Metabolic panel results or complete blood counts that are outside of the normal reference range and are considered clinically relevant by the study physician
  • Cold, flu, or upper respiratory condition at screening
  • Currently participating in a clinical or dietary intervention study
  • *Non-English speaking volunteers will be excluded for safety reasons, as we do not have staff that can adequately provide interpretation services that can explain and answer questions with regard to study procedures.

Treatment and study plan

Cocoa flavanols I

Other

Capsules containing Mars Cocoa Extract manufactured by the Cocoapro® process and containing 300mg of cocoa flavanols per capsule consumed for 2 weeks.

Control I

Other

Cocoa-based, flavanol-free, control-matched capsules consumed for 2 weeks.

Cocoa flavanols II

Other

Capsules containing Mars Cocoa Extract manufactured by the Cocoapro® process and containing 300mg of cocoa flavanols per capsule consumed for 2 weeks.

Control II

Other

Cocoa-based, flavanol-free, control-matched capsules consumed for 2 weeks.

Primary outcomes

  1. Individual changes in systolic blood pressure (in office)

    Time frame: Baseline and 2, 4, 6, 8 and 10 weeks following intervention

    assessed as systolic blood pressure

  2. Individual changes in diastolic blood pressure (in office)

    Time frame: Baseline and 2, 4, 6, 8 and 10 weeks following intervention

    assessed as diastolic blood pressure

  3. Individual changes in augmentation index (in office)

    Time frame: Baseline and 2, 4, 6, 8 and 10 weeks following intervention

    assessed as augmentation index

  4. Individual changes in central blood pressure (in office)

    Time frame: Baseline and 2, 4, 6, 8 and 10 weeks following intervention

    assessed as central blood pressure

  5. Individual changes in blood pressure (at home)

    Time frame: Daily for 2 weeks between 0, 2, 4, 6, 8 and 10 weeks of intervention

    self monitoring blood pressure

  6. Individual changes in pulse wave velocity (in office)

    Time frame: Baseline and 2, 4, 6, 8 and 10 weeks following intervention

    assessed as pulse wave velocity

  7. Individual changes in lipid profile

    Time frame: Baseline and 2, 4, 6, 8 and 10 weeks following intervention

    Total cholesterol, LDL, HDL and Triglycerides

Secondary outcomes

  1. Individual changes in flavanol metabolites in plasma and urine

    Time frame: Baseline and 2, 4, 6, 8, 10 weeks following intervention

    flavanol/methylxanthine metabolites in plasma and urine

  2. Individual changes in methylxanthine metabolites in plasma and urine

    Time frame: Baseline and 2, 4, 6, 8, 10 weeks following intervention

    flavanol/methylxanthine metabolites in plasma and urine

  3. Individual changes in CMP

    Time frame: Baseline and 2, 4, 6, 8, 10 weeks following intervention

    comprehensive metabolic panel

  4. Individual changes in Step test performance

    Time frame: Baseline and 2, 4, 6, 8, 10 weeks following intervention

    Volunteers will be asked to step up and down on a platform (7 inches high) at a rate of 23 steps per minute for no more than 3 minutes. Blood pressure will be measured before and after the step test.

Sponsors and collaborators

Lead sponsor

University of California, Davis

Other

Collaborators

  • Mars, Inc.

Registry information

Important dates

Study start
2018
Primary completion
2021
Study completion
2021
First posted
Jul 16, 2018
Registry last updated
May 20, 2022

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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