Study on the absorption of amino acid calsium chelate and bioequivalence
JIAN Ling-yan,HE Xiao-jing,ZHAO Li-mei,QIU Feng,SUN Ya-xin(Department of Pharmacy,Shengjing Hospital of China Medical University,Liaoning Shenyang 110004,China)
OBJECTIVE To compare the absorption of calcium from calcium amino acid chelate and calcium carbonate using 24-h urine calcium method conducted in healthy male volunteers. METHODS In a three-way crossover study,either a blank or 600 mg of calcium in the form of calcium carbonate,500 mg of calcium in calcium amino acid chelate were administered orally to 21 healthy male volunteers who had fasted overnight. Urine calcium was measured afterward. Absorption of the different calcium-supplement regimens was evaluated by changes in 24-h urinary excretion of calcium. After calcium was administered,absorption of the different calcium-supplement regimens was evaluated by changes in calcium ions concentration in 24-h urinary excretion. RESULTS Urine calcium increments,max excretory rate,Tmax and excretory percent for calcium amino acid chelate calcium carbonate were(61.8±32.8)mg vs. (37.5±29.1)mg,(4.76±2.46 )mg·h-1 vs. (3.5±1.5)mg·h-1,(10.3%±5.5%) vs. (6.2%±4.8%),(3.4±2.6)h vs. (4.0±4.4)h,respectively. Compare with carbonate calcium,bioavailability of calcium amino acid chelate was(471.0%±630.5%). CONCLUSION Our data indicate that calcium amino acid chelate is superior to calcium carbonate using 24 h urine calcium method,which partly represented calcium absorption. Calcium amino acid chelate may offer significant advantages as a dietary calcium supplement.