Dark Chocolate Intake and Cardiovascular Diseases: A Mendelian Randomization Study

Previous intervention studies have shown some benefits of dark chocolate for the cardiovascular system, but it has not been established whether dark chocolate intake is associated with the risk of cardiovascular diseases (CVDs). To investigate the causality between dark chocolate intake and the risk of CVDs, a Mendelian randomization (MR) study was conducted. We obtained summary-level data on dark chocolate intake and CVDs from publicly available genome-wide association studies. In this MR study, the main approach was to use a fixed-effect model with inverse variance weighted (IVW) and evaluate the robustness of the results via sensitivity analysis. We found that dark chocolate intake was significantly associated with the reduction of the risk of essential hypertension (EH) (OR = 0.72; 95% CI, 0.59–0.88; p = 1.55 × 10 − 3 ), as well as with the potential decreased risk of venous thromboembolism (VTE) (OR = 0.61; 95% CI, 0.43–0.86; p = 5.44× 10 − 3 ). However, no association was found between dark chocolate intake and the other 10 CVDs. A sensitivity analysis of the MR analysis of VTE revealed only marginal horizontal pleiotropy (intercept = 1.76× 10 − 2 ; p = 0.04). Our study provides evidence for a causality between dark chocolate intake and a reduced risk of EH, which has important implications for the prevention of EH in the population.