Whiting S J, Wood R, Kim K
University of Saskatchewan, Saskatoon, Canada.
J Am Acad Nurse Pract. 1997 Apr;9(4):187-92.
Calcium is necessary for the prevention and treatment of diseases such as osteoporosis, hypertension, and, possibly, colon cancer. Supplementation is useful when dietary calcium intake is low, as is the current situation in North America. There are many factors to consider before recommending any one form of supplement. A consideration for calcium carbonate tablets is whether the tablet disintegrates and whether or not a lack of food or acid in the stomach will hinder utilization. Other forms of calcium, particularly the chelated calcium salts, are better absorbed in fasting achlorhydric subjects but have less calcium per gram of supplement. Interaction of calcium with other mineral nutrients and the presence of contaminating metals has focused attention on safety. Based on present evidence, chelated calcium and refined calcium carbonate tablets (including those labeled as antacids) may be safely and effectively ingested by most people at doses generally recommended for treatment or prevention of osteoporosis. One should not exceed 2,000 mg of calcium, except at the advice of their health care provider, as inadvertent mineral deficiencies may arise. Persons at risk for developing milk-alkali syndrome, such as thiazide users and persons with renal failure, should be identified and monitored for alkalosis and hypercalcemia when using calcium supplements.
钙对于预防和治疗诸如骨质疏松症、高血压以及可能的结肠癌等疾病是必需的。当饮食中钙摄入量较低时，如北美目前的情况，补充钙剂是有用的。在推荐任何一种补充剂形式之前，有许多因素需要考虑。对于碳酸钙片，需要考虑的是片剂是否会崩解，以及胃中缺乏食物或胃酸是否会阻碍其吸收利用。其他形式的钙，特别是螯合钙盐，在空腹无胃酸的受试者中吸收更好，但每克补充剂中的钙含量较少。钙与其他矿物质营养素的相互作用以及污染金属的存在，已使人们关注其安全性。根据目前的证据，大多数人按照通常推荐用于治疗或预防骨质疏松症的剂量，可安全有效地摄入螯合钙和精制碳酸钙片（包括那些标为抗酸剂的片剂）。除非有医疗保健提供者的建议，否则钙摄入量不应超过2000毫克，因为可能会无意中出现矿物质缺乏。有发生乳碱综合征风险的人群，如使用噻嗪类药物的人和肾衰竭患者，在使用钙补充剂时，应予以识别并监测是否出现碱中毒和高钙血症。
