The Effects of 1 Egg per Day on Iron and Anemia Status among Young Malawian Children: A Secondary Analysis of a Randomized Controlled Trial

Abstract

Objectives Young children with diets lacking diversity with low consumption of animal source foods are at risk of iron deficiency anemia (IDA). Our objectives were to determine the impact of supplementing diets with 1 egg/day on: (1) plasma ferritin, soluble transferrin receptor (sTfR), body iron index (BII), and hemoglobin concentrations; and (2) the prevalence of iron deficiency (ID), anemia, and IDA. Methods Malawian 6-9mo old infants in the Mazira trial (clinicaltrials.gov; NCT03385252) were individually randomized to receive 1 egg/day for 6mo (n = 331) or continue their usual diet (n = 329). In this secondary analysis, hemoglobin, plasma ferritin, sTfR, c-reactive protein (CRP), and α-1-acid glycoprotein (AGP) were measured at enrollment and 6mo follow-up. Iron biomarkers were corrected for inflammation. Ferritin, sTfR, BII, and hemoglobin were compared between groups using linear regression. Prevalence ratios (PR) for anemia (hemoglobin<11g/dL) and ID (ferritin<12µg/L, sTfR>8.3mg/L, or BII<0mg/kg) between groups were compared using log binomial or modified Poisson regression. Results A total of 585 children were included in this analysis (Egg: n = 286; Control: n = 299). At enrollment, the total prevalence of anemia was 61% and did not differ between groups. At 6mo follow-up, groups did not differ in geometric mean concentration of hemoglobin [mean (95%CI); Egg: 10.9g/dL (10.7, 11.1); Control: 11.1 (10.9, 11.2)] and inflammation-adjusted ferritin [Egg: 6.52µg/L (5.98, 7.10); Control: 6.82 (6.27, 7.42)], sTfR [Egg: 11.34mg/L (10.92, 11.78); Control: 11.46 (11.04, 11.89)] or BII [Egg: 0.07mg/kg (0.06, 0.09); Control: 0.07 (0.05, 0.08)]. There were also no group differences in anemia [Egg: 46%; Control 40%; PR: 1.15 (95% CI: 0.96, 1.38)], ID [PR: 0.99 (0.94, 1.05)], or IDA [PR: 1.12 (0.92, 1.36)]. Conclusions Providing eggs daily for 6mo did not affect iron status or anemia prevalence in this context. Other interventions are needed to address the high prevalence of ID and anemia among young, Malawian children Trial registration: Clinical Trials NCT03385252

Child-Owned Poultry Intervention Effects on Hemoglobin, Anemia, Concurrent Anemia and Stunting, and Morbidity Status of Young Children in Southern Ethiopia: A Cluster Randomized Controlled Community Trial

“…Our intervention increased hemoglobin by 0.53 g/dl, unlike the egg trial in Malawi, which provided eggs to 6–9 months old children for daily consumption (Mazira project) and reported no improvement in hemoglobin concentration, ferritin, soluble transferrin receptor, and body iron index. No difference was also seen among egg and no egg groups in anemia, iron deficiency, and iron deficiency anemia prevalence [ 26 ]. The high burden of iron deficiency at enrolment and sustained inflammation during the study period was presented as the reason why egg intake could not improve the iron and anemia status of the children.…”

“…It is important to note the context difference between the Mazira project and our project. In the Mazira children, iron deficiency is found concurrently with 93% of the anemia and more than 98% to 100% prevalence of iron intake inadequacy was recorded at midline and end line [ 26 , 47 ]. Although we did not measure iron status, children in our project had higher hemoglobin levels and lower anemia prevalence than the Mazira children at baseline; most likely indicating better iron status.…”

“…A trial that compared meat with multi-micronutrient-fortified rice-soy cereal reported no difference in anemia rates but significantly lowered the iron deficiency among the cereal group [ 25 ]. After providing one egg daily for six months in Malawi, no difference was found with the control group (no egg) in the prevalence of anemia, iron deficiency and iron deficiency anemia, hemoglobin levels, and iron status [ 26 ]. Little research has been done in Ethiopia on the effects of nutrition interventions on anemia among infants and young children.…”

Effect of egg on hemoglobin level of pregnant women

“…Protein also has the greatest influence on iron absorption compared to carbohydrates and lipids (Kobayashi et al, 2015). Although several studies have stated that giving eggs does not affect hemoglobin, even egg yolk reduce iron absorption (Chai et al, 2019;Kobayashi et al, 2015;Werner et al, 2022) Previous studies have stated that protein intake from egg yolks reduces iron absorption because it can combine with phosvitin and form iron complexes that do not dissolve in the small intestine (Chai et al, 2019;Kobayashi et al, 2015). Previous studies have stated that protein intake from egg yolks reduces iron absorption because it can combine with phosvitin and form iron complexes that do not dissolve in the small intestine (Chai et al, 2019;Kobayashi et al, 2015).…”

“…Until now the potential impact of eggs on iron status is still unclear (Werner et al, 2022), so further studies are needed…”