Zinc absorption from maize-based meals enriched with edible house crickets: a randomized crossover stable-isotope...

Edible insects have been proposed as a novel and sustainable source of protein and other essential nutrients for human consumption but nutrient absorption efficiency is still uncertain. We investigated zinc absorption from house crickets (Acheta domesticus) in a single-center and single-blinded cross-over study with children aged 24-36 months old in Kenya from September-November 2021. For this, children were randomized to consume two different experimental meals labeled with stable isotopes of zinc (Zn) at two different days, separated by a wash-out period of one month. Primary endpoints were the differences in amount of absorbed zinc (AZ) from maize-based meals enriched with intrinsically ⁶⁷Zn-labeled house crickets (2.61 mg Zn, n = 28) in comparison with meals enriched with ⁶⁸Zn (low-enriched: 0.90 mg Zn, n = 29); high-enriched: 3.24 mg Zn, n = 28) or with intrinsically ⁶⁷Zn-labeled low-chitin cricket flour (2.51 mg Zn, n = 25), whereas the secondary endpoints were the differences in fractional zinc absorption. We found that AZ from meals with whole crickets (geometric mean: 0.36 mg; 95%CI: 0.30, 0.43) was 2.6 times higher than from low-enriched maize meals (0.14 mg; 0.11, 0.16; P < 0.001), while it was not different from low-chitin cricket flour meals. Absorbed zinc from both cricket meals was higher than that from high-enriched meals. No severe adverse side events were reported. We conclude that edible house crickets are a good source of well-absorbable zinc, and their increased consumption could contribute to the alleviation of zinc deficiency. This trial was registered at the Pan African Clinical Trials Registry as PACTR202104533831364.