Study of Dietary Additive Phosphorus on Proteinuria and Fibroblast Growth Factor-23

The Study of Dietary Additive Phosphorus on Proteinuria and FGF-23 (SODA-POP) was a single-center, randomized, double-blind, two-period cross-over study that examined the effect of higher vs. lower phosphorus intake for 3 week periods, achieved by addition of commercially available diet beverages and breakfast bars to diet on albuminuria and fibroblast growth factor 23, in adults with presumed early chronic kidney disease (estimated glomerular filtration rate \>= 45 ml/min/1.73m2; and urine albumin/creatinine ratio \>=17 mg/g for men or \>=25 mg/g for women).