Epidemiological evidence associating dietary calcium and calcium metabolism with blood pressure

Fourteen reports have identified an association between lower dietary calcium consumption and higher blood pressure in adults. The relationship between dietary calcium and blood pressure status of humans may be modified by a wide variety of demographic, environmental, life-style, and nutritional factors. Reduced dietary calcium intake may be a proximate cause of several of the reported biochemical abnormalities of Ca²⁺ metabolism including the reductions in serum ionized Ca²⁺ concentrations and increases in circulating parathyroid hormone levels. The paradoxical increases in intracellular free Ca²⁺ observed in hypertension on low dietary Ca²⁺ intake suggest that a primary defect in the cellular handling of Ca²⁺ may exist, possible mediated through defective Ca²⁺ adenosine triphosphatase pump activity.