title: Consumption of yogurts fortified in vitamin D and calcium reduces serum parathyroid hormone and markers of bone resorption: a double-blind randomized controlled trial in institutionalized elderly women.
abstract: BACKGROUND
  Nutritional prevention of bone deterioration with fortified foods seems particularly suitable in institutionalized elderly women at risk of vitamin D deficiency, secondary hyperparathyroidism, increased bone resorption, and osteoporotic fracture.
  
  
  OBJECTIVE
  The objective was to evaluate whether fortification of yogurts with vitamin D and calcium exerts an additional lowering effect on serum PTH and bone resorption markers as compared with isocaloric and isoprotein dairy products in elderly women.
  
  
  METHODS
  A randomized double-blind controlled-trial, 56-day intervention was conducted in institutionalized women (mean age 85.5 years) consuming 2 125-g servings of either vitamin D- and calcium-fortified yogurt (FY) at supplemental levels of 10 μg/d vitamin D₃ and 800 mg/d calcium or nonfortified control yogurt (CY) providing 280 mg/d calcium.
  
  
  RESULTS
  The endpoints were serum changes from baseline (day 0) to day 28 and day 56 in 25-hydroxyvitamin-D (25OHD), PTH, and bone resorption markers tartrate-resistant acid phosphatase isoform-5b (TRAP5b), the primary outcome, and carboxyl-terminal cross-linked telopeptide of type I collagen (CTX).
  
  
  RESULTS
  At day 56, serum 25OHD increased (mean ± SEM) by 25.3 ± 1.8 vs 5.2 ± 2.5 nmol/L in FY (n = 29) and CY (n = 27), respectively (P < .0001). The corresponding changes in PTH were -28.6% ± 7.2% vs -8.0% ± 4.3% (P = .0003); in TRAP5b, -21.9% ± 4.3% vs 3.0% ± 3.2% (P < .0001); and in CTX, -11.0% ± 9.7% vs -3.0% ± 4.1% (P = .0146), in FY and CY, respectively. At day 28, these differences were less pronounced but already significant for 25OHD, PTH, and TRAP5b.
  
  
  CONCLUSIONS
  This study in institutionalized elderly at high risk for osteoporotic fracture suggests that fortification of dairy products with vitamin D₃ and calcium provides a greater prevention of accelerated bone resorption as compared with nonfortified equivalent foods.
authors: Division of Bone Diseases, University Hospitals and Faculty of Medicine, CH-1211 Geneva, Switzerland. jean-philippe.bonjour@unige.ch
authors: Jean-Philippe
authors: JP
authors: Bonjour
authors: Valérie
authors: V
authors: Benoit
authors: Flore
authors: F
authors: Payen
authors: Marius
authors: M
authors: Kraenzlin
mesh_terms: D000135:Acid Phosphatase / Q000097:blood; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D050071:Bone Density Conservation Agents / Q000008:administration & dosage / Q000378:metabolism / Q000627:therapeutic use; D001862:Bone Resorption / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control*; D002136:Calcium, Dietary / Q000008:administration & dosage / Q000627:therapeutic use*; D002762:Cholecalciferol / Q000008:administration & dosage / Q000378:metabolism / Q000627:therapeutic use*; D024042:Collagen Type I / Q000097:blood; D004311:Double-Blind Method; D005260:Female; D005527:Food, Fortified / Q000032:analysis; D005602:France / Q000453:epidemiology; D006707:Homes for the Aged; D006801:Humans; D006962:Hyperparathyroidism, Secondary / Q000097:blood / Q000178:diet therapy / Q000453:epidemiology / Q000209:etiology; D007527:Isoenzymes / Q000097:blood; D009735:Nursing Homes; D015663:Osteoporosis, Postmenopausal / Q000097:blood / Q000178:diet therapy* / Q000453:epidemiology / Q000209:etiology; D058866:Osteoporotic Fractures / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control; D010281:Parathyroid Hormone / Q000097:blood*; D010455:Peptides / Q000097:blood; D012306:Risk; D000071681:Tartrate-Resistant Acid Phosphatase; D014808:Vitamin D Deficiency / Q000097:blood / Q000178:diet therapy / Q000453:epidemiology / Q000209:etiology; D015014:Yogurt / Q000032:analysis
chemical_list: D015415:Biomarkers; D050071:Bone Density Conservation Agents; D002136:Calcium, Dietary; D024042:Collagen Type I; D007527:Isoenzymes; C470125:PTH protein, human; D010281:Parathyroid Hormone; D010455:Peptides; C052929:collagen type I trimeric cross-linked peptide; D002762:Cholecalciferol; D000135:Acid Phosphatase; D000071681:Tartrate-Resistant Acid Phosphatase