Discussion
mineral deficiency
ZINC DEFICIENCY, MINERAL DEFICIENCY
Minerals are necessary for proper cellular function in infants and children, especially during critical periods of growth and development. In this study of young Malawians, the egg intervention did not change plasma magnesium, copper, selenium, or zinc concentrations compared to the control group. At the 6-months, plasma iron concentrations were significantly lower in the intervention group compared the control group. Additionally, the likelihood of mineral deficiency was particularly concerning for zinc.Plasma selenium levels were not increased by provision of one egg daily for six months in these young Malawian children. Similar results have been reported in adults who consume eggs daily, but little is known about the effect of eggs in young childrenAt baseline, prevalence of zinc deficiency was found to be equivalent to previous reports ranging from 60–66% in children and adults living in MalawiIron can be particularly sensitive to other components of the food matrix. As shown in adults, iron bioavailability can be decreased by proteins like phosvitin, ovalbumin, and ovotransferrin, which are all found in eggs. These proteins lead to iron chelation and decrease its absorption in processes intended to prevent microbial growth in eggsThe Mazira Project was designed as a replication trial building on the Lulun Project in Ecuador. The Lulun trial found significant improvements after intervention on linear growth velocity and plasma DHA and choline levelsOne notable difference in this Malawian context compared to previous studies was type of foods reported on dietary intake surveysThere were strengths and limitations to acknowledge in this study. It was a rigorously designed randomized control trial with high adherence (71%) to the intervention based on 24-h recall at the 6 month follow-up and a comprehensive set of mixed methods including detailed dietary recallsLastly, we were unable to determine total calcium levels or the effect of the intervention in these Malawian children. We attempted to use ICP-MS to measure calcium isotope 43, which resulted in a good recovery. In general, the abundance of Ca (43) is 0.13%, which was used to extrapolate total calcium concentrations. However, levels were found to be considerably lower than normal ranges for young children