Nicar M J, Pak C Y
J Clin Endocrinol Metab. 1985 Aug;61(2):391-3. doi: 10.1210/jcem-61-2-391.
Fourteen normal subjects took 1000 mg calcium orally as calcium citrate or calcium carbonate. The amount of calcium absorbed was estimated from the rise in urinary calcium. The urinary calcium following calcium citrate load significantly higher (by 20-66%), whether expressed as the total amount or as the increment above basal (fasting) excretion. Thus, calcium citrate provides a more optimum calcium bioavailability than calcium carbonate.
14名正常受试者口服1000毫克柠檬酸钙或碳酸钙形式的钙。根据尿钙的增加来估计钙的吸收量。无论以总量还是以高于基础（空腹）排泄量的增量来表示，柠檬酸钙负荷后的尿钙都显著更高（高出20 - 66%）。因此，与碳酸钙相比，柠檬酸钙具有更优的钙生物利用度。
