The predictors of different measures of dietary diversity among one-year-olds in South Africa

Abstract

Objectives: A study was undertaken to compare a range of dietary diversity indicators and their predictors among one-year-olds. Design: Multivariate regression analysis was employed, where dietary diversity indicators are the outcome variables and the main predictor variables are access to resources and maternal education. Three different dietary diversity indicators are analysed: a count of food items, a count of food groups and a Healthy Food Diversity Index. Subjects and setting: The study included participants of Birth to Twenty Plus, a longitudinal cohort study of children born in 1990 in Johannesburg, South Africa (n = 1 030). Results: There is a low correlation between measures of dietary diversity based on simple counts of food items/groups and the Healthy Food Diversity Index. Further, the predictors differ depending on which type of indicator is used. Access to resources (measured by an asset index) was found to be associated with an increase in counts of food items/groups but at a decreasing rate, while the opposite was found for the Healthy Food Diversity Index. There was no significant association between maternal education and the counts of food items/groups, while maternal education was positively associated with the Healthy Food Diversity Index. Conclusions: More sophisticated measures of dietary diversity that also capture the healthiness of foods and their distribution in the diet, rather than just the number or variety, may be useful in understanding dietary patterns among children and what influences them. Maternal education appears to be particularly important for healthy food consumption among young children, while access to resources has a more complex association, with differential results at low and high levels.