Dietary intake and bone status with aging

Osteoporosis and related fractures represent major public health problems that are expected to increase dramatically in importance as the population ages. Dietary risk factors are particularly important, as they are modifiable. However, most of the attention to dietary risk factors for osteoporosis has focused almost exclusively on calcium and vitamin D. Recently, there has been considerable interest in the effects of a variety of other nutrients on bone status. These include minerals--magnesium, potassium, copper, zinc, silicon, sodium; vitamins--vitamin C, vitamin K, vitamin B12, vitamin A; and macronutrients--protein, fatty acids, sugars. In addition, foods and food components, including milk, fruit and vegetables, soy products, carbonated beverages, mineral water, dietary fiber, alcohol and caffeine have recently been examined. Together the evidence clearly suggests that prevention of bone loss through diet is complex and involves many nutrients and other food constituents. For many, results remain inconclusive and in some cases contradictory. However, it is increasingly clear that our exposure to a complex of nutrients and food constituents interacts to affect bone status. In addition to identifying the role of individual components, there is a great need to understand the interactions of these factors within diets and, increasingly, in the presence of nutrient supplements. Furthermore, genetic factors are likely to interact with these dietary exposures, increasing the complexity of these effects. With advances in both genetics and nutrition, improved understanding of all these interactions will contribute to effective recommendations for prevention of bone loss and osteoporosis in the aging population.