Nutrition and Risk for Osteoporosis

Publisher Summary Nutrition affects bone health in two qualitatively distinct ways. Bone tissue deposition, maintenance, and repair are the result of cellular processes, and the cells of bone responsible for these functions are as dependent upon nutrition as are the cells of any other tissue. The production of bone matrix, for example, requires the synthesis and post-translational modification of collagen and an array of other proteins. Nutrients involved in such synthesis include protein, the vitamins C, D, and K, and the minerals copper, manganese, and zinc. Phosphorus is also involved indirectly in these cellular activities. Additionally, the skeleton serves as a very large nutrient reserve for two minerals, calcium and phosphorus, and the size of that reserve is dependent in part on the daily balance between absorbed intake and excretory loss of these two minerals. Bone mass is also dependent upon a variety of non-nutritional factors, such as genetics, mechanical loading, and hormonal status. These dependencies complicate the interpretation of low bone mass values because, while low bone mass always means a reduced calcium reserve, a simple reduction in bone mass does not necessarily mean that it had a nutritional cause. This chapter discusses the problems faced in the investigation of nutritional effects on bone, including nutrition-specific problems and bone-specific problems.