Data underlying the publication: Absorption of iron from edible house crickets: a randomized crossover stable-isotope study in humans

In this exploratory study, we assessed fractional iron absorption from house crickets (Acheta domesticus) consumed with refined (low-phytate, noninhibiting) or nonrefined (high-phytate, inhibiting) meals. Intrinsically [57Fe]-labeled and control crickets were reared. Six iron-balanced experimental meals were randomlyadministered crossover to 20 iron-depleted females (serum ferritin <25 μg/L; 18–30 y old), in 2 time-blocks of 3 consecutive days, 2 wk apart. Three meals consisted of refined maize flour porridge with either [57Fe]-labeled crickets, [58Fe]SO4 (reference meal), or unlabeled crickets plus [54Fe]SO4. The other 3 meals consisted ofnonrefined maize flour porridge with the same respective additions. Blood samples were drawn to assess the 14-d isotope enrichment in erythrocytes, and meal-specific fractional iron absorption was calculated. In vitro digestion was used to explore possible explanations for unexpected findings. Mean fractional iron absorption from 57Fe-labeled house crickets with refined maize porridge (3.06%) and from refined maize porridge with unlabeled crickets (4.92%) was lower than from the referencemeal (14.2%), with respective mean differences of−11.1% (95% CI: −12.6%, −9.68%) and −9.29% (95% CI: −10.8%, −7.77%). Iron absorption from all meals based on unrefined maize porridge was low (<3%), and did not differ for the 2 meals with crickets compared with the reference meal. In vitro digestion showed that chitin, chitosan, and calcium limited iron bioaccessibility to a large extent. Iron absorption from house crickets and fortified maize porridge with crickets is low, which may be explained by the presence of chitin and other inhibitors in the cricket biomass. This trial was registered at https://www.trialregister.nl as NL6821.

本探索性研究评估了受试者食用家蟋蟀（Acheta domesticus）搭配精制（低植酸、无铁吸收抑制作用）或未精制（高植酸、具有铁吸收抑制作用）膳食时的铁分数吸收率（fractional iron absorption）。本研究饲养了内在标记[57Fe]的家蟋蟀与对照家蟋蟀。将6种铁平衡试验膳食采用随机交叉试验设计，于间隔2周的2个连续3天时间段内，给予20名铁缺乏女性受试者（血清铁蛋白<25 μg/L，年龄18~30岁）。其中3种膳食为精制玉米粉粥，分别搭配[57Fe]标记家蟋蟀、[58Fe]硫酸铁（参比膳食）或未标记家蟋蟀联合[54Fe]硫酸铁；另外3种膳食为未精制玉米粉粥，搭配上述对应组分。采集血液样本以检测红细胞内14天的同位素丰度，并计算各试验膳食对应的铁分数吸收率。此外通过体外消化实验，对本次研究中的意外结果进行潜在成因探索。搭配精制玉米粉粥的[57Fe]标记家蟋蟀的平均铁分数吸收率为3.06%，未标记家蟋蟀联合精制玉米粉粥的平均铁分数吸收率为4.92%，二者均低于参比膳食的14.2%，对应的平均差值分别为−11.1%（95%置信区间：−12.6%，−9.68%）与−9.29%（95%置信区间：−10.8%，−7.77%）。所有基于未精制玉米粉粥的试验膳食的铁吸收率均较低（<3%），且含家蟋蟀的2种膳食与参比膳食的铁吸收率无显著差异。体外消化实验结果显示，几丁质（chitin）、壳聚糖（chitosan）与钙可在很大程度上限制铁的生物可及性（iron bioaccessibility）。食用家蟋蟀以及添加家蟋蟀的强化玉米粉粥时的铁吸收率较低，该现象可通过蟋蟀生物质中存在的几丁质与其他铁吸收抑制剂得到解释。本试验已在https://www.trialregister.nl注册，注册号为NL6821。