Association between protein consumption and height and weight among young children: analysis of Multiple Indicator Cluster Surveys

Early childhood nutrition determines cognitive development and physical health throughout the life course. Prior work has suggested protein deficiency, in particular tryptophan, may be a major driver of stunted growth. We evaluated the association between the consumption of animal versus plant protein sources and anthropometric z-scores using Multiple Indicator Cluster Surveys for children aged 1-4 years: Central African Republic 2010 (n = 7843), Ghana 2011 (n = 5887), Mali 2009 (n = 17 496) and Sierra Leone 2017 (n = 9254). In the past 24 h, 72% had consumed any animal-sourced foods (fish, dairy, egg, meat, liver, milk, yogurt, cheese) and 45% had consumed legumes. We used a doubly robust regression that reduced confounding using three-moment entropy balancing on survey parameters, demographics (age, gender) and socioeconomic status (urban residence, mother's education, wealth quintile), followed by survey-weighted multivariable linear regression with outcomes interviewer-measured height-for-age and weight-for-age z-scores. Height-for-age and weight-for-age z-scores were greater for children who had consumed animal-source food (0.134 (0.082, 0.186) and 0.075 (0.029, 0.120)); children who had consumed legumes had higher weight (0.056 (0.021, 0.091)) but not height (0.015 (-0.028, 0.059)). Our findings align with biomedical research implicating essential amino acids as key mediators of growth and intestinal function, and suggest a role for complete protein and essential amino acid deficiency as a driver of environmental enteric dysfunction. This article is part of the theme issue 'Biological, biomedical and environmental drivers of stunting'.