Public Health, School of Medicine, Griffith University, Gold Coast Campus, Southport, Queensland, Australia.
Institute of Nutrition and Food Science, University of Dhaka, Dhaka, Bangladesh.
Trop Med Int Health. 2022 May;27(5):509-514. doi: 10.1111/tmi.13750. Epub 2022 Apr 19.
Phytate, an important component of plant origin foods, works as a chelator for mineral nutrients such as iron. Estimating the phytate-iron molar ratio is a traditional method to assess the bioavailability of dietary iron, and a ratio >1 is suggestive of poor absorption of iron through the intestinal mucosa. In Bangladesh, the ratio is considerably higher; nonetheless, the haemoglobin and ferritin status are satisfactory. Hence, we appraised phytate-iron molar ratios and concomitant haemoglobin and ferritin status.
Dietary intake of iron and phytate was estimated in non-pregnant non-lactating women and school-age children from a nationally representative survey. The phytate-iron molar ratios were estimated. Linear regressions on haemoglobin for the phytate-iron molar ratios and on molar ratios predicting inflammation-adjusted ferritin were performed.
The median ratios were 6.12 in women and 5.47 in children, with corresponding haemoglobin concentrations of 12.6 and 12.5 g/dl. Hypothetical lowering of the ratios by ~50% revealed a nominal increment of haemoglobin and ferritin.
The standard cut-off phytate-iron molar ratio of >1 is inconsistent with the iron and haemoglobin status of the Bangladeshi population. One plausible explanation for the inconsistency is a non-dietary environmental factor-groundwater iron. Isotope studies incorporating the iron from dietary and the drinking groundwater sources are needed to establish a ratio which might better explain iron bioavailability.
植酸是植物性食物的重要组成部分，它可以作为矿物质营养素（如铁）的螯合剂。估计植酸盐-铁摩尔比是评估膳食铁生物利用度的传统方法，比值>1 表明铁通过肠黏膜吸收不良。在孟加拉国，该比值相当高；尽管如此，血红蛋白和铁蛋白状况仍令人满意。因此，我们评估了植酸盐-铁摩尔比以及伴随的血红蛋白和铁蛋白状况。
我们在一项具有全国代表性的调查中，估计了非妊娠非哺乳期妇女和学龄儿童的铁和植酸的膳食摄入量。估计了植酸盐-铁摩尔比。对血红蛋白进行线性回归，以评估植酸盐-铁摩尔比和预测炎症调整铁蛋白的摩尔比。
女性的中位数比值为 6.12，儿童为 5.47，相应的血红蛋白浓度为 12.6 和 12.5g/dl。假设将比值降低约 50%，血红蛋白和铁蛋白的数值略有增加。
标准的>1 的植酸盐-铁摩尔比值与孟加拉国人的铁和血红蛋白状况不一致。不一致的一个合理解释是一种非饮食环境因素——地下水铁。需要进行同位素研究，将来自膳食和饮用水源的铁纳入其中，以建立一个可能更好地解释铁生物利用度的比值。
