Calcium, why and how much?

Although calcium (Ca) is pivotal for the prevention of osteoporosis, its role in the prevention of other unrelated diseases such as arterial hypertension, cancer of the colon and nephrolithiasis is perplexing. No unitarian hypothesis explaining these unrelated effects of Ca has been postulated. Cytosolic Ca concentration is 10,000-fold lower than in the extracellular space, and this gradient is tightly maintained. Abnormal elevation of cytosolic Ca causes cell damage and death. Parathyroid hormone is a Ca agonist and the suppression of its secretion by Ca could explain the beneficial role of Ca intake in multiple diseases. Thus, parathyroid ablation improves hypertension in rats and cardiomyopathy in hamsters. Since anthropologic data suggests a higher Ca intake, of approximately 1,600 1,600 mg/day, in preneolithic than in modern diets, it is likely that our levels of PTH on genetically predisposed subjects with a loose cellular Ca control may aggravate frequent modern diseases and the process of aging. A higher Ca intake in both sexes should be one of the goals of preventive medicine of our time.