The many faces of phosphate in the diet

Background: Hyperphosphatemia represents one of the central risk factors in patients with advanced stage renal insufficiency. In addition, large epidemiological studies revealed signs that higher serum phosphate levels were especially associated with cardiovascular morbidity. The quantitative phosphate intake in nutrition plays a key role in this context. Objective: This review article deals with the currently available data on phosphate-associated mortality and morbidity in patients with and without chronic kidney disease (CKD). It also discusses the topic of dietary phosphate intake via natural and processed foods and on their potential influence on phosphate balance. Material and methods: Current studies on the influence of different phosphate sources on laboratory values and biomarkers, on clinically relevant surrogate parameters and additional endpoints were screened, summarized and evaluated. Results: There are significant differences concerning phosphate balance with respect to the origin of phosphate in the nutrition. The least uptake is observed with vegetarian sources, uptake of phosphate from meat products is intermediate, while inorganic phosphate additives are resorbed with high efficiency. Conclusion: The quality and amount of phosphate intake have a large influence on phosphate balance, which is especially important for CKD patients at risk for cardiovascular events. For improved management of risk reduction, adequate labeling of food items concerning phosphate contents is required and must be appropriately enforced. © 2017, Springer Medizin Verlag Berlin.