The Effects of One Egg Per Day on Vitamin A Status Among Young Malawian Children: A Secondary Analysis of a Randomized Controlled Trial

E Rochelle Werner; Marjorie J Haskell; Charles D Arnold; Bess L Caswell; Lora L Iannotti; Chessa K Lutter; Kenneth M Maleta; Christine P Stewart

doi:10.1016/j.cdnut.2023.100053

The Effects of One Egg Per Day on Vitamin A Status Among Young Malawian Children: A Secondary Analysis of a Randomized Controlled Trial

Curr Dev Nutr. 2023 Feb 23;7(3):100053. doi: 10.1016/j.cdnut.2023.100053. eCollection 2023 Mar.

Authors

E Rochelle Werner¹, Marjorie J Haskell¹, Charles D Arnold¹, Bess L Caswell^{1

2}, Lora L Iannotti³, Chessa K Lutter⁴, Kenneth M Maleta⁵, Christine P Stewart¹

Affiliations

¹ Institute for Global Nutrition, University of California, Davis, Davis, CA, United States.
² Western Human Nutrition Research Center, US Department of Agriculture, Davis, CA, United States.
³ E3 Nutrition Lab, Washington University in St Louis, St Louis, MO, United States.
⁴ RTI International, Washington, DC, United States.
⁵ School of Public Health and Family Medicine, Kamuzu University of Health Sciences, Blantyre, Malawi.

Abstract

Background: Vitamin A deficiency (VAD) is common in populations with limited dietary diversity and access to vitamin A-rich foods.

Objectives: This analysis aimed to determine the impact of supplementing children's diets with 1 egg/d on the concentration of plasma retinol and RBP and the prevalence of VAD.

Methods: Children age 6-9 mo living in the Mangochi district of Malawi were individually randomly assigned to receive 1 egg/d for 6 mo (n = 331) or continue their usual diet (n = 329) in the Mazira trial (clinicaltrials.gov; NCT03385252). This secondary analysis measured plasma retinol by HPLC and RBP, CRP, and α-1-acid glycoprotein (AGP) by ELISA techniques at enrollment and 6 mo follow-up. Retinol and RBP were adjusted for inflammation, and mean concentrations were compared between groups using linear regression models. In addition, prevalence ratios of VAD (retinol <0.7 μmol/L) were compared between groups using log-binomial or modified Poisson regression models.

Results: After 6 mo of study participation, 489 were assessed for retinol (egg: n = 238; control: n = 251), and 575 (egg: n = 281; control: n = 294) were assessed for RBP. Prevalence of inflammation (CRP >5 mg/L or AGP >1 g/L: 62%) and inflammation-adjusted VAD (7%) at enrollment did not differ between groups. At follow-up, the egg intervention group did not differ from the control in inflammation-adjusted retinol [geometric mean (95% CI); egg: 1.10 μmol/L (1.07, 1.13); control: 1.08 (1.05, 1.12)], RBP [egg: 0.99 μmol/L (0.96, 1.02); control: 0.97 (0.94, 1.00)], or prevalence of VAD [egg: 6%; control: 3%; prevalence ratio: 1.87 (0.83, 4.24)].

Conclusions: Provision of 1 egg/d did not impact VAD, plasma retinol, or RBP among young children in rural Malawi, where the prevalence of VAD was low. Curr Dev Nutr 2023;x:xx.This trial was registered at [clinicaltrials.gov] as [NCT03385252].

Keywords: Malawi; RBP; animal-source foods; eggs; infant and young child feeding; retinol; sub-Saharan Africa; vitamin A; vitamin A deficiency (VAD).

Associated data

ClinicalTrials.gov/NCT03385252