Analysing the drivers of dietary diversity, diet quality and household food security in developing Asia: Evidence from urban Vietnam and rural Bangladesh

Abstract

This thesis explores the drivers influencing dietary diversity, diet quality and overall food security, using different approaches for urban and rural households in emerging Asia. The first empirical study investigates the possible mechanisms through which modern food environments may affect Vietnamese households’ dietary diversity and diet quality. The analysis uses primary data collected in 2016 and 2017 from 1,700 households in urban Hanoi and Ho Chi Minh City, as part of the Vietnam Urban Food Consumption and Expenditure Study. To measure household diet quality, Household Dietary Diversity Scores (HDDS), and consumption frequencies of micronutrients (vitamin A and heme iron) and a macronutrient (protein), are calculated using seven-day food recall data. A Poisson regression model is estimated using a two-step control function approach to address the potential endogeneity of key explanatory variable, modern market food expenditure shares. Higher modern market food expenditure shares are significantly associated with consumption of heme iron, however, no significant relationship is found for consumption of vitamin A and protein. Results from system of equations show that modern market food expenditure shares are significantly associated with diet quality through indirect linkages with HDDS. The second study investigates the relationship between ‘western’ foods consumed away-from-home, and the diet quality of 4,997 individuals in Vietnam. Diet quality is measured using 24-hour food diaries which include information on food consumed both at-home and away-from-home. Dependent variables explored are individual daily caloric intake and percent of total calories from the consumption of carbohydrates, fat and protein. After testing for potential endogeneity of the key independent variable, individuals’ daily calorie shares from western food-away-from-home (western FAFH), we find that western FAFH has a significant association with high calorie intake. Our results for macronutrient shares show that western FAFH is associated with a higher intake of fat. The third study examines the relationship between farm households’ food security status, and health and economic shocks using a nationally representative sample of 3,448 rural farm households from a secondary dataset, the 2012 Bangladesh Integrated Household Survey. A consolidated Food Security Index (FSI) is calculated using a suite of food security indicators: food consumption score, food expenditure share and livelihood coping strategies to capture rural farm households’ food consumption, as well as their economic vulnerability. Empirical results from an ordered probit model controlling for village-level unobservables suggest that both health and economic shocks are significantly associated with FSI. Further results show that marginal and small farming households are more vulnerable to food insecurity when health and/or economic shocks impact their households. The results from the two analyses using Vietnam data suggest that policy makers need to be aware of the potential impact of increasingly ‘obesogenic food environments’ on consumer food consumption behaviour and diet quality. Finally, the results of the third analysis using rural data from Bangladeshi farming households, highlights the need for policy makers to consider the unique needs of farming households, the most vulnerable group, when designing food security interventions to address shocks or to eliminate food insecurity among rural populations.