ABSTRACT
The proper dietary calcium intake and calcium supplementation, when indicated, are important factors in the acquisition of peak bone mass during youth and in the prevention of fractures in old age. In addition to its deposition in bone, calcium confers an increase in its resistance and exhibits important activities in different enzymatic pathways in the body (e.g., neural, hormonal, muscle-related and blood clotting pathways). Thus, calcium supplementation can directly or indirectly affect important functions in the body, such as the control of blood pressure, plasma glucose, body weight, lipid profile and endothelial function. Since one publication reported increased cardiovascular risk due to calcium supplementation, many researchers have studied whether this risk actually exists; the results are conflicting, and the involved mechanisms are uncertain. However, studies that have evaluated the influence of the consumption of foods rich in calcium have reported no increase in the cardiovascular risk, which suggests that nutritional intake should be prioritized as a method for supplementation and that the use of calcium supplements should be reserved for patients who truly need supplementation and are unable to achieve the recommended daily nutritional intake of calcium.
Calcium supplementation; dietary calcium; osteoporosis; cardiovascular safety; cardiovascular mortality
In addition to confer resistance to bones and teeth, calcium plays an important role in several regulatory pathways in the body. It acts by modifying the activity of cellular receptors, in signal transduction and as a cofactor in various enzyme systems, thus modulating the secretion of hormones, such as insulin, mediating contractility of striated and smooth muscle, neuronal transmission and cardiac conduction besides being required in the intrinsic, extrinsic and common pathways of the coagulation system. The maintenance of serum calcium levels is required for the proper functioning of organism.