Effects of dark chocolate Intake on Physical Functions in Japanese Subjects

Introcuction: This study aimed to evaluate the effects of dark chocolate consumption on physical functions (blood pressure, the fasting serum lipid profile, cognitive function, and markers of oxidative stress and inflammation) in Japanese subjects. Methods:The clinical trial included 385 healthy Japanese subjects aged 45-69 years, who were not taking regular medication and had no history of allergy to cacao. All subjects ate 25 g of dark chocolate for 4 weeks, and 347 subjects completed the study. Results:The backgrounds of the subjects are as follows; the average age was 55.0 ± 6.5 years, and BMI was 22.5 ± 3.2 kg/m2. Body weight and BMI remained almost unchanged during the 4 weeks. Consumption of dark chocolate was found to decrease systolic and diastolic blood pressure significantly, increase HDL-cholesterol, and improve a marker of cognitive function (brain-derived neurotrophic factor [BDNF]). Subjects with 8-hydroxy-2’-deoxyguranosin (8-OHdG) concentration ≥ 10.52 ng/mg creatinine at baseline (the highest quartile) were found to have a reduction of 8-OHdG (a marker of oxidative stress) at the end of the study. We also observed a reduction of high-sensitivity C-reactive protein (hs-CRP) concentration after consumption of dark chocolate by subjects in the highest quartile (hs-CRP ≥ 620 μg/L) at baseline. We assessed quality of life using SF-36v2®, and the scores indicated improvement in the health-related quality of life. Conclusion:Our study has shown that daily consumption of dark chocolate decreased blood pressure, and increased HDL-cholesterol, BDNF and the score for quality of life. It is anticipated that regular consumption of polyphenol-rich foods should lead to a decrease in the incidence of atherosclerotic disease and improvement of cognitive function.