Background: Dietary sources of calcium and vitamin D are recommended as a first-line strategy in prevention of osteoporosis-related fractures but their public health and economic impact has never been studied. Methods: We designed a population-based model to forecast the potential health outcomes and medical effectiveness of the daily administration of dairy supplements containing 800 IU of vitamin D and 1 g of calcium in cohorts of subjects, from both genders, aged 50, 60, 70 and 80 years. Annual costs of dairy products were tested at epsilon 150, epsilon 250 and epsilon 350. Results: In total, the daily intake of vitamin-D rich dairy products reduces by 30,376 and 16,105 events the number of osteoporotic fractures in women and men respectively and permits to gain 6605 and 6144 life-years, in women and men respectively. This intervention is cost-effective from 70 years on in the general population and from 60 years on in patients at increased risk of osteoporotic fractures. Conclusion: The recommendation to use dairy products as the preferred source of calcium and vitamin D in aging males and females is supported by public health and health economic analyses.