McClure ST, et al. - In the DASH (Dietary Approaches to Stop Hypertension) trial, researchers evaluated if percentage urinary phosphorus excretion was constant across 3 dietary patterns. Overall 459 prehypertensive and stage 1 hypertensive adults (52% male, 56% black) were included, who were randomly assigned to the control diet, a diet rich in fruits and vegetables (FV diet), or a diet rich in fruits, vegetables, and low-fat dairy with reduced saturated fat and cholesterol (DASH diet) for 8 wk following a 3-wk run-in on a typical American (control) diet. Because urinary phosphorus excretion across dietary patterns ranged widely, it was strongly indicated by the findings that urinary phosphorus excretion should not be used as a recovery biomarker for dietary phosphorus consumption.