Background and Purpose - No prospective studies have examined the association between calcium intake and the risk of cardiovascular disease in Japanese populations with a low mean calcium intake.
Methods - Between 1988 and 1990, 110 792 Japanese subjects ( 46 465 men and 64 327 women) 40 to 79 years of age without a history of stroke, coronary heart disease, or cancer, completed a lifestyle questionnaire including food intake frequency under the Japan Collaborative Cohort (JACC) Study for Evaluation of Cancer Risk Sponsored by Monbusho. By the end of 1999, after 515 029 person years of follow-up, 566 deaths from stroke ( 101 subarachnoid hemorrhages, 140 intraparenchymal hemorrhages, and 273 ischemic strokes) and 234 deaths from coronary heart disease had been documented.
Results - The intake of total calcium tended to be inversely associated with mortality from total stroke but not from coronary heart disease or total cardiovascular disease for men and women. The inverse association with dairy calcium intake was apparent for total stroke, both hemorrhagic and ischemic. The multivariate relative risk for men with highest versus lowest quintiles of dairy calcium intake was 0.53 (95% CI, 0.34 to 0.81) for total stroke, 0.46 (0.23 to 0.91) for hemorrhagic stroke, and 0.53 (0.29 to 0.99) for ischemic stroke; corresponding relative risks for women were 0.57 (0.38 to 0.86), 0.51 (0.28 to 0.94), and 0.50 (0.27 to 0.95).
Conclusions - Dietary calcium intake from dairy products was associated with reduced mortality from stroke for Japanese men and women.