Effect of dark chocolate on nitric oxide serum levels and blood pressure in prehypertension subjects

Acta Med Indones. 2011 Oct;43(4):224-8.


Aim: to investigate the effect of consumption of dark chocolate 30 g/day for fifteen days on Nitric oxide (NO) serum levels and blood pressure in male and female employees with prehypertension.

Methods: the study was a parallel randomized clinical trial. A total of thirty-two subjects was divided into two groups using block randomization. Sixteen subjects received 30 g/day dark chocolate and dietary counseling (treatment group) and the other 16 subjects received white chocolate 25 g/day and dietary counseling (control group) for fifteen days. Data collected in this study consisted of age, physical activity, body massa index, intake of energy, intake of sodium, and intake of polyphenol, NO serum levels and blood pressure. The measurement of NO serum levels was done in pre- and after- treatment, while blood pressure was assessed in pre- , during- and after- treatment. Statistical analysis was performed using independent t-test for normal distribution data and Mann-Whitney test for not normal distribution data, with the level of significancy of 5%.

Results: after 15 days treatment, NO serum level between treatment and control groups were significantly different 7.70 ± 3.84 vs 1.92(-0.79 ± 17.78) (p=0.001). Both groups had decreased systolic and diastolic blood pressure. Systolic blood pressure was different significantly between groups after treatment 120.64 ± 8.47 vs 131.19 ± 7.45 (p=0.001), while diastolic blood pressure was not significant 74.14 ± 6.30 vs 77.44 ± 10.29 (p=0.308).

Conclusion: in prehypertension subjects, dark chocolate 30 g/day increased NOx serum levels and decreased systolic blood pressure after 15 days of treatment.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Blood Pressure / drug effects*
  • Blood Pressure Determination
  • Body Mass Index
  • Cacao / metabolism*
  • Candy
  • Energy Intake
  • Female
  • Flavonoids* / metabolism
  • Flavonoids* / therapeutic use
  • Humans
  • Male
  • Monitoring, Physiologic
  • Motor Activity
  • Nitric Oxide / metabolism*
  • Phenols / metabolism
  • Phenols / therapeutic use
  • Prehypertension* / diagnosis
  • Prehypertension* / metabolism
  • Sodium, Dietary / adverse effects
  • Sodium, Dietary / metabolism
  • Treatment Outcome


  • Flavonoids
  • Phenols
  • Sodium, Dietary
  • Nitric Oxide