Osteoporosis is one of the leading health problems of women today, and the expectation is that more than 41 million women worldwide will be affected within the next 20 years if current trends are not reversed. Prevention of osteoporosis must be a focus for nurses, rather than merely the treatment of the problem. The majority of bone mass is developed during the adolescent and young adulthood years, with nearly 90% of skeletal mass accumulated by age 18. Current research has demonstrated that young women's intake of calcium is significantly below the recommended dietary intake. This article reviews the role and functions of calcium, how it is transported, and factors that may significantly increase or impair the absorption of this macronutrient. Strategies are described that will assist nurses in assessing the patient's diet and making appropriate recommendations regarding the intake of calcium and other micronutrients. A more in-depth and thorough understanding of this important mineral will enable nurses to strengthen their knowledge and confidence in helping patients and themselves change the focus from treating the disease to the improvement and maintenance of healthy bones and the prevention of other health conditions in women.