Effect of calcium phosphate and vitamin D₃ supplementation on bone remodelling and metabolism of calcium, phosphorus, magnesium and iron.
BACKGROUND
The aim of the present study was to determine the effect of calcium phosphate and/or vitamin D₃ on bone and mineral metabolism.


METHODS
Sixty omnivorous healthy subjects participated in the double-blind, placebo-controlled parallel designed study. Supplements were tricalcium phosphate (CaP) and cholecalciferol (vitamin D₃). At the beginning of the study (baseline), all subjects documented their normal nutritional habits in a dietary record for three successive days. After baseline, subjects were allocated to three intervention groups: CaP (additional 1 g calcium/d), vitamin D₃ (additional 10 μg/d) and CaP + vitamin D₃. In the first two weeks, all groups consumed placebo bread, and afterwards, for eight weeks, the test bread according to the intervention group. In the last week of each study period (baseline, placebo, after four and eight weeks of intervention), a faecal (three days) and a urine (24 h) collection and a fasting blood sampling took place. Calcium, phosphorus, magnesium and iron were determined in faeces, urine and blood. Bone formation and resorption markers were analysed in blood and urine.


RESULTS
After four and eight weeks, CaP and CaP + vitamin D₃ supplementations increased faecal excretion of calcium and phosphorus significantly compared to placebo. Due to the vitamin D₃ supplementations (vitamin D₃, CaP + vitamin D₃), the plasma 25-(OH)D concentration significantly increased after eight weeks compared to placebo. The additional application of CaP led to a significant increase of the 25-(OH)D concentration already after four weeks. Bone resorption and bone formation markers were not influenced by any intervention.


CONCLUSIONS
Supplementation with daily 10 μg vitamin D₃ significantly increases plasma 25-(OH)D concentration. The combination with daily 1 g calcium (as CaP) has a further increasing effect on the 25-(OH)D concentration. Both CaP alone and in combination with vitamin D₃ have no beneficial effect on bone remodelling markers and on the metabolism of calcium, phosphorus, magnesium and iron.


BACKGROUND
NCT01297023.
Ulrike
U
Trautvetter
Nadja
N
Neef
Matthias
M
Leiterer
Michael
M
Kiehntopf
Jürgen
J
Kratzsch
Department of Nutritional Physiology, Institute of Nutrition, Friedrich Schiller University of Jena, Dornburger Str, 24, D-07743, Jena, Germany. b6jage@uni-jena.de.
Gerhard
G
Jahreis
D000328:Adult; D000368:Aged; D016723:Bone Remodeling / Q000187:drug effects*; D002118:Calcium / Q000097:blood; D002130:Calcium Phosphates / Q000008:administration & dosage* / Q000494:pharmacology*; D002136:Calcium, Dietary / Q000008:administration & dosage*; D002762:Cholecalciferol / Q000008:administration & dosage*; D004311:Double-Blind Method; D005243:Feces / Q000737:chemistry; D005260:Female; D006801:Humans; D007501:Iron / Q000378:metabolism; D008274:Magnesium / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D010758:Phosphorus / Q000378:metabolism
D002130:Calcium Phosphates; D002136:Calcium, Dietary; D002762:Cholecalciferol; D010758:Phosphorus; C020243:calcium phosphate; D007501:Iron; D008274:Magnesium; C018392:tricalcium phosphate; D002118:Calcium