title: Acute effects of very-low-protein diet on FGF23 levels: a randomized study.
abstract: OBJECTIVE
  High levels of fibroblast growth factor 23 are associated with mortality, CKD progression, and calcification in CKD patients. The aim of this pilot study is to assess whether a very-low-protein diet (0.3 g/kg per day) with a consequent low intake of phosphorus would reduce fibroblast growth factor 23 compared with a low-protein diet (0.6 g/kg per day) in CKD patients not yet on dialysis.
  
  
  METHODS
  A prospective, randomized, controlled crossover study was performed in which 32 patients were randomized into two groups. Group A (16 patients) received a very-low-protein diet (0.3 g/kg body wt per day) supplemented with ketoanalogues during the first week and a low-protein diet during the second week, and group B (16 patients) received a low-protein diet during the first week and a very-low-protein diet during the second week. Fibroblast growth factor 23, seric, and urinary phosphate levels were measured at baseline and the end of each study period.
  
  
  RESULTS
  After only 1 week of the very-low-protein diet, reductions in fibroblast growth factor 23 levels (33.5%), serum phosphate (12%), and urinary phosphate (34%) with the very-low-protein diet compared with the low-protein diet were observed. Serum and urinary phosphate levels and protein intake were significant determinants of fibroblast growth factor 23 (95% confidence interval=1.04-1.19, 1.12-1.37, and 1.51-2.23, respectively).
  
  
  CONCLUSIONS
  A very-low-protein diet supplemented with ketoanalogues reduced fibroblast growth factor 23 levels in CKD patients not yet on dialysis.
authors.affiliation: Department of Medicine, Complex Unit of Nephrology, A. Landolfi Hospital, Solofra, Italy. br.diiorio@gmail.com
authors.forename: Biagio
authors.initials: B
authors.lastname: Di Iorio
authors.forename: Lucia
authors.initials: L
authors.lastname: Di Micco
authors.forename: Serena
authors.initials: S
authors.lastname: Torraca
authors.forename: Maria Luisa
authors.initials: ML
authors.lastname: Sirico
authors.forename: Luigi
authors.initials: L
authors.lastname: Russo
authors.forename: Andrea
authors.initials: A
authors.lastname: Pota
authors.forename: Francesco
authors.initials: F
authors.lastname: Mirenghi
authors.forename: Domenico
authors.initials: D
authors.lastname: Russo
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood / Q000652:urine; D002908:Chronic Disease; D018592:Cross-Over Studies; D018753:Diet, Protein-Restricted; D015536:Down-Regulation; D005260:Female; D000089703:Fibroblast Growth Factor-23; D005346:Fibroblast Growth Factors / Q000097:blood*; D006801:Humans; D007558:Italy; D007674:Kidney Diseases / Q000097:blood / Q000178:diet therapy* / Q000652:urine; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D016226:Phosphorus, Dietary / Q000097:blood / Q000652:urine; D010865:Pilot Projects; D011446:Prospective Studies; D012044:Regression Analysis; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers; C000717427:FGF23 protein, human; D016226:Phosphorus, Dietary; D005346:Fibroblast Growth Factors; D000089703:Fibroblast Growth Factor-23