Griffin Ian J, Abrams Steven A
USDA/ARS Children's Nutrition Research Center, and Section of Neonatology, Department of Pediatrics, Baylor College of Medicine, 1100 Bates Street, Houston, TX 77030, USA.
Br J Nutr. 2005 Apr;93 Suppl 1:S105-10. doi: 10.1079/bjn20041344.
During the last 50 years, a variety of methods have been developed to estimate Ca absorption in man. Mass balances were initially used, but these were unable to accurately measure fractional Ca absorption because they cannot distinguish unabsorbed dietary Ca from endogenous faecal Ca excretion (excretion of previously absorbed Ca back into the gut). A number of isotopic methods have been developed that can measure true fractional Ca absorption, employing radioisotopes, stable isotopes, or both. Different methods involve collection of urine, faecal or plasma samples. Of the currently available methods, the dual isotope tracer method with a timed urine collection is probably the most precise and reliable. It is also relatively straightforward to carry out and avoids the need for a faecal collection. The purpose of the present paper is to discuss the general advantages and disadvantages of the different methods of Ca absorption. In addition, the limitations the different methods have in examining the possible effects of non-digestible oligosaccharides on Ca absorption will be discussed.
在过去50年里，人们开发了多种方法来估计人体对钙的吸收情况。最初使用的是质量平衡法，但这些方法无法准确测量钙的吸收分数，因为它们无法区分未吸收的膳食钙和内源性粪便钙排泄（先前吸收的钙排泄回肠道）。现已开发出多种同位素方法，这些方法可以使用放射性同位素、稳定同位素或两者兼用来测量真正的钙吸收分数。不同的方法涉及收集尿液、粪便或血浆样本。在目前可用的方法中，采用定时尿液收集的双同位素示踪法可能是最精确和可靠的。它实施起来也相对简单，并且无需收集粪便。本文的目的是讨论不同钙吸收方法的一般优缺点。此外，还将讨论不同方法在研究不可消化寡糖对钙吸收可能产生的影响时所存在的局限性。
