Subgroup dairy products consumption on the risk of stroke and CHD: A systematic review and meta-analysis

Background: There is no global consensus about the relationship between dairy consumption and cardiovascular diseases (CVD). This study aimed at integrating the results of several studies to predict the dairy effects on CVD, e.g. stroke and CHD.    Methods: In the present study, some major databases such as Scopus, Science Direct, and PubMed were searched up to September 2014. All prospective cohort studies dealing with dairy products consumption and CVD were surveyed regardless of their publication date or language. This reference population includes all individuals without any delimitation with regard to age, gender, or race. The quality of the study was evaluated using STROBE Checklist. Study selection and data extraction were done by 2 independent researchers separately. The indices in this study were RR and HR. The random model was used to combine the results.   Results: Out of 6234 articles, 11 were included in the meta-analysis. No relationship was found between stroke and consumption of milk, cream, and butter, and the results are as follow: RR = 0.91 (95%CI: 0.81-1.01) for milk, RR = 0.97 (95%CI: 0.88-1.06) for cream, and RR = 0.95 (95%CI: 0.85-1.07) for butter. However, cheese was found to decrease stroke risk: RR = 0.93 (95%CI: 0.88-0.99). The relationship of CHD with consumption of milk, cheese, cream, and butter are as follows, respectively: RR = 1.05 (95% CI: 0.96-1.15), RR = 0.90 (95%CI: 0.81-1.01), RR = 0.96 (95% CI: 0.87-1.06), and RR = 0.99 (95%CI: 0.89-1.11). In other words, no relationship existed between dairy products and CHD.    Conclusion: No relationship was found between consumption of various dairy products and CHD or stroke, except for cheese that decreased stroke risk by 7%. Considering the small number of studies, the result of the present study is not generalizable and more studies need to be conducted.