title: Stimulation by citric acid of calcium and phosphorus bioavailability in rats fed a calcium-rich diet.
abstract: The effect of dietary citric acid supplementation on calcium (Ca) and phosphorus (P) bioavailability was studied in rats fed 3 different diets containing 0.1, 0.5 or 1.0 g/100g Ca during 7 weeks. Citric acid supplementation increased intestinal Ca and P absorption and the Ca and P retention/intake ratio only in rats fed the 1% Ca diet. It also increased the P concentration of bone ashes in rats fed the 0.5% Ca diet (18.9 +/- 0.2 vs 17.5 +/- 0.5%) and the 1% Ca diet (20 +/- 0.1 vs. 19 +/- 0.3%), and the Ca bone ash concentration in rats fed the 1% Ca diet (36.7 +/- 0.4 vs. 35.7 +/- 0.5%). In rats fed the 1% Ca diet, plasma P concentration was decreased by citric acid supplementation (2.09 +/- 0.10 vs. 2.45 +/- 0.08 mmol/l) while urinary P excretion was increased (18.2 +/- 2.3 vs. 2.0 +/- 0.3 mmol/4 days), together with a decrease in plasma calcitriol concentration (54.4 +/- 2.6 vs. 79.6 +/- 2.5 ng/l), but no change of the circulating parathyroid hormone level. This study indicates that citric acid supplementation together with a Ca-rich diet allows to obtain an increased retention of Ca and P in bone. The prolonged administration of Ca citrate supplements may therefore help to increase bone mineral concentration.
authors.affiliation: Laboratoire du Métabolisme Minéral des Mammifères, Ecole Pratique des Hautes Etudes, Physiologie, Faculté de Pharmacie, Chatenay-Malabry, France.
authors.forename: B
authors.initials: B
authors.lastname: Lacour
authors.forename: S
authors.initials: S
authors.lastname: Tardivel
authors.forename: T
authors.initials: T
authors.lastname: Drüeke
mesh_terms: D000818:Animals; D001682:Biological Availability; D015519:Bone Density; D001842:Bone and Bones / Q000378:metabolism; D002118:Calcium / Q000097:blood / Q000493:pharmacokinetics* / Q000652:urine; D019343:Citric Acid / Q000494:pharmacology*; D004032:Diet; D005269:Femur; D007408:Intestinal Absorption / Q000187:drug effects; D008297:Male; D010758:Phosphorus / Q000097:blood / Q000493:pharmacokinetics* / Q000652:urine; D051381:Rats; D017208:Rats, Wistar; D015430:Weight Gain
chemical_list: D010758:Phosphorus; D019343:Citric Acid; D002118:Calcium