Association between dietary calcium intake and the risk of cardiovascular disease among Korean adults

Although dietary calcium intake is associated with a risk of cardiovascular disease (CVD), it has not been studied extensively in Asian populations. We therefore investigated the association between dietary calcium intake and CVD among Korean adults and the effect of obesity on this association. In total, 9186 participants were included in the analysis after excluding 844 with prevalent CVD/cancer or implausible energy intake. Nutrient intake, including dietary calcium, was estimated using a validated semi-quantitative food frequency questionnaire. CVD included myocardial infarction, coronary artery disease, and stroke per the World Health Organization criteria. Cox proportional hazards models were used to calculate multivariate-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs). In the fully adjusted model, HRs of CVD across increasing quintiles of dietary calcium intake were 1.0 (reference), 0.85 (95% CI: 0.66–1.10), 0.77 (95% CI: 0.58–1.02), 0.59 (95% CI: 0.42–0.83), and 0.72 (95% CI: 0.48–1.08); a significant linear trend was detected (p for trend = 0.04). However, this association varied according to the obesity status. High dietary calcium intake was associated with a reduced CVD risk among nonobese participants (body mass index [BMI] < 25 kg/m2; p for trend = 0.02), whereas this was not significant among obese participants (BMI ≥ 25 kg/m2; p for trend = 0.88). The association between dietary calcium intake and incident CVD may be influenced by obesity status. We provide evidence for developing dietary calcium intake guidelines for Koreans, allowing for the effects of obesity.