Recommendations for dietary calcium intake and bone health: the role of health literacy

Osteoporosis, a common disease of the skeleton, involves microarchitecturaldeterioration of the bone matrix and depletion of bonemineral; this results in an increased susceptibility to fracture [1]. Postfracture,there is a plethora of financial, personal and psychosocialoutcomes, including reduced mobility, impairment of daily activities,inability to work and loss of confidence [2,3]. A hip fracture has themost severe implications: one in five individuals die within the firstyear, while 60% of individuals who survive a hip fracture still requireassistance to walk one year later, and 33% are totally dependent or areadmitted to a nursing home [2,4]. Bone mass is an important predictorof osteoporosis, and future fracture risk [5], and calcium plays animportant role in normal growth, development and maintenance of theskeleton [6], including providing a dynamic store to maintain theintra- and extra-cellular calcium pools [7]. Calcium homeostasis isregulated by an integrated hormonal system that involves calcitonin,parathyroid hormone (PTH) and the PTH receptor, and 1,25-dihydroxyvitamin D and the vitamin D receptor [7,8], along withserum ionized calcium, and the calcium-sensing receptor [9]. Whenplasma concentrations of ionized calcium fall below optimal levels,bone resorption increases in order to restore the mineral equilibrium