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.