I. Basic Phosphorus Physiology.- 1. The Story of Phosphorus.- 2. Overview of Phosphorus Homeostasis.- 3. Hormonal Regulation of Phosphorus Homeostasis: Parathyroid Hormone, Fibroblast Growth Factor 23, and Klotho.- II. Phosphorus in food.- 4. Phosphorus in the Modern Food Supply: Underestimation of Exposure.- 5. Nutritional Aspects of Phosphorus Compounds in Foods.- 6. Phosphorus Additives in Food Processing.- 7. Effects of Natural and Added Phosphorus Compounds in Foods in Health and Disease.- 8. Phosphorus Utilization in Animal Agriculture.- 9. Technical Aspects about Measuring Phosphorus in Food.- III. Phosphorous - Nutrient interactions.- 10. Interaction Between Calcium and Phosphorus and the Relationship to Bone Health.- 11. Phosphate Deficiency and the Phosphate Depletion Syndrome: Pathophysiology, Diagnosis, and Treatment.- 12. Dietary Phytate and Interactions with Mineral Nutrients.- IV. Phosphorus and Disease.- 13. Phosphorus and Kidney Disease: Mechanisms for Perturbed Phosphorus Homeostasis in Chronic Kidney Disease.- 14. Hidden Forms of Phosphorus in the Diet: Impact in the General Population and in Individuals with Chronic Kidney Disease.- 15. Dietary Phosphorus and Bone Disease.- 16. Phosphorus and Cardiovascular Disease.- 17. Phosphorus and Malignancies.