Effects of dark chocolate on blood pressure and cardiovascular risk in men

Theobromine Consumption From Cocoa and Cardiovascular Risk Factors in Humans: Evidence for Health Claims

NA · Chiang Mai University · NCT06820944

This study tests if eating dark chocolate can lower blood pressure and improve heart health in men with high blood pressure.

Quick facts

PhaseNA
Study typeInterventional
Enrollment42 (estimated)
Ages35 Years to 70 Years
SexMale
SponsorChiang Mai University (other)
Locations1 site (Mueang, Chiang Mai)
Trial IDNCT06820944 on ClinicalTrials.gov

What this trial studies

This clinical trial investigates the impact of dark chocolate consumption on blood pressure and trimethylamine N-oxide levels in Thai males with hypertension. Participants will consume either dark chocolate or white chocolate daily for 14 days, followed by a wash-out period before switching to the other type. The study aims to determine if theobromine, a compound found in dark chocolate, contributes to any observed changes in cardiovascular risk factors. The trial is conducted in Chiang Mai, Thailand, with a focus on male participants aged 35-70 years.

Who should consider this trial

Good fit: Ideal candidates are Thai males aged 35-70 years with hypertension and a BMI less than 30 kg/m².

Not a fit: Patients with chronic diseases, those taking medications for hypertension or cholesterol, or individuals who consume caffeine or alcohol excessively may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could provide evidence that dark chocolate consumption may help lower blood pressure and improve cardiovascular health in hypertensive patients.

How similar studies have performed: Previous studies have suggested potential cardiovascular benefits of cocoa, but this specific approach focusing on theobromine in a crossover design is relatively novel.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion criteria

* Male
* Age between 35 to 70 years
* BMI less than 30 kg/m\^2
* Systolic blood pressure between 130 to 159 mmHg or Diastolic blood pressure between 85 to 99 mmHg.
* Do not smoke.

Exclusion criteria

* Cannot drink beverages and consume foods that have caffeine.
* Take medicine to lower cholesterol and triglyceride levels, treat high blood pressure, or diabetes.
* Have liver and kidney inflammation.
* Use antibiotics within 1 month of study.
* Use choline or probiotic supplements regularly within 1 month of study.
* Consume more than 30 alcoholic drinks per week.
* Have chronic diseases.

Where this trial is running

Mueang, Chiang Mai

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.

View on ClinicalTrials.gov →

Conditions: Hypertension, cocoa consumption, theobromine, trimethylamine-n-oxide, crossover, randomized trial, chocolate consumption

Last reviewed 2026-05-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.