Blood pressure response to dietary calcium intervention in humans. Epidemiological and experimental studies have suggested that dietary calcium deficiency may lead to the development of hypertension. This article reviews findings in human trials on calcium intervention with special reference to the responses of blood pressure and biochemical variables. Calcium supplementation consistently resulted in decreased blood pressure in a subset of hypertensive and normotensive subjects, but led to increased blood pressure in some hypertensive patients. The variable blood pressure responses to calcium supplementation could not be predicted on the basis of routine biochemical parameters and appeared to be due to differences in the backgrounds of the subjects and/or the design and size of the trials. It is concluded that further studies are required on the hypotensive effect of calcium supplementation. 