title: Increased calcium absorption from synthetic stable amorphous calcium carbonate: double-blind randomized crossover clinical trial in postmenopausal women.
abstract: Calcium supplementation is a widely recognized strategy for achieving adequate calcium intake. We designed this blinded, randomized, crossover interventional trial to compare the bioavailability of a new stable synthetic amorphous calcium carbonate (ACC) with that of crystalline calcium carbonate (CCC) using the dual stable isotope technique. The study was conducted in the Unit of Clinical Nutrition, Tel Aviv Sourasky Medical Center, Israel. The study population included 15 early postmenopausal women aged 54.9 ± 2.8 (mean ± SD) years with no history of major medical illness or metabolic bone disorder, excess calcium intake, or vitamin D deficiency. Standardized breakfast was followed by randomly provided CCC or ACC capsules containing 192 mg elemental calcium labeled with 44Ca at intervals of at least 3 weeks. After swallowing the capsules, intravenous CaCl2 labeled with 42Ca on was administered on each occasion. Fractional calcium absorption (FCA) of ACC and CCC was calculated from the 24-hour urine collection following calcium administration. The results indicated that FCA of ACC was doubled (± 0.96 SD) on average compared to that of CCC (p < 0.02). The higher absorption of the synthetic stable ACC may serve as a more efficacious way of calcium supplementation.
authors.affiliation: The Unit of Clinical Nutrition, Tel-Aviv Sourasky Medical Center, Tel-Aviv, Israel.
authors.forename: Nachum
authors.initials: N
authors.lastname: Vaisman
authors.forename: Galit
authors.initials: G
authors.lastname: Shaltiel
authors.forename: Michal
authors.initials: M
authors.lastname: Daniely
authors.forename: Oren E
authors.initials: OE
authors.lastname: Meiron
authors.forename: Assaf
authors.initials: A
authors.lastname: Shechter
authors.forename: Steven A
authors.initials: SA
authors.lastname: Abrams
authors.forename: Eva
authors.initials: E
authors.lastname: Niv
authors.forename: Yami
authors.initials: Y
authors.lastname: Shapira
authors.forename: Amir
authors.initials: A
authors.lastname: Sagi
mesh_terms: D002118:Calcium / Q000378:metabolism*; D002119:Calcium Carbonate / Q000008:administration & dosage / Q000494:pharmacology*; D018592:Cross-Over Studies; D003460:Crystallization; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007408:Intestinal Absorption / Q000187:drug effects*; D008875:Middle Aged; D017698:Postmenopause / Q000187:drug effects / Q000502:physiology*
chemical_list: D002119:Calcium Carbonate; D002118:Calcium
keywords: ABSORPTION; AMORPHOUS CALCIUM CARBONATE; CALCIUM BIOAVAILABILITY; POSTMENOPAUSE; STABLE ISOTOPES