Oral calcium and blood pressure: a controlled intervention trial

In a double-blind, placebo-controlled trial with 58 normotensive female students, the effect of oral-calcium supplementation (1500 mg Ca++/day for 6 wk) on diastolic and systolic blood pressure was studied while students were consuming a low-calcium diet (500 mg Ca++/day) by restricting the intake of dairy products. Results show that, in both the calcium- and placebo-supplemented groups, blood pressure values decreased slightly and no effect of oral-calcium supplementation on blood pressure could be demonstrated. In addition, at baseline neither systolic nor diastolic blood pressure correlated with habitual calcium intake. Diastolic but not systolic blood pressure correlated significantly with body mass index (r = 0.31, p = 0.01). It is concluded that oral-calcium supplementation for 6 wk does not influence blood pressure in young, healthy normotensive females consuming low-calcium diet.