Towards food system innovations : characterizing food system components and evaluating pilots in Viet Nam

This thesis uses a food system lens to characterize the components of a local food system (Viet Nam) and identify the potential leverages for innovation and intervention. It also evaluates pilot interventions to improve consumption of healthy foods as an outcome of the food system, contributing to emerging scientific evidence base on food systems innovations.

In Chapter 1, I set the stage by explaining how food systems research can help address the global health and development concerns, presenting the research questions and discussing the key topics of the thesis: priorities in food systems research, food environment and school-based interventions for healthier diets. The specific research questions are: How can research priorities be defined for a local food system, considering practices from other domains? (Chapter 2); How do food environment characteristics vary across a local transect? How are their relationships with consumption and nutrition outcomes? (Chapter 3); What are the potential impacts of interventions to improve children’s consumption in a food environment setting? (Chapter 4 & 5).

The first study in this thesis (Chapter 2) critically reviews the inclusive process of condensing a large amount of data into a national food system profile and determining research priorities for Vietnam’s food system. From the case study of Viet Nam, we conclude that food system research priority setting can successfully adopt several good practices from health and nutrition priority setting, such as the assessment of existing evidence with extensive data, a clear method for deciding on priorities, inclusion of a broad range of multidisciplinary stakeholders, and adoption of transparency principles. Additionally, the exercise has to take into account the characteristics of food system analysis that make the task of prioritization more challenging, namely the multi-sector, multi-outcome and dynamic natures of food systems.

In chapter 3, we found significant differences in food availability across the three sites in North Viet Nam (Chapter 3). The urban area exhibits the highest food outlet density and variety, while the rural food environment is characterized by a limited variety in which traditional independent small grocery stores make up the major share. Urban and peri-urban households enjoy a closer proximity to food service shops than rural households who depend the most on at-home consumption and home-grown products. We argued that the widespread availability and low prices of unhealthy foods even in the most accessibility-derived communities might be responsible for the observation that peri-urban and rural areas had higher consumption of ultra-processed foods than in urban area. Additionally, we pointed to the lack of diversity of healthy foods in the disadvantaged neighborhoods as an important leverage to tackle child undernutrition.

Chapter 4 and 5 provide the results of the evaluation of two pilot interventions. We found that information-based interventions, either in the form of weekly lessons or educational prompts, can have significant effects in the short run on interested outcomes, such as nutritional knowledge (chapter 4)  and healthy food choice (chapter 5), but these effects can quickly dissolve after a relatively short period. The poor quality of the meals provided to children during lunch prevented the children from eating more fruit and vegetables, even though they were better aware of the issues of not eating enough FAV. Addressing the school meals’ taste quality is crucial to the effectiveness of nutrition education. We found that providing access to healthy food in the school environment could be a good way to raise children’s healthy food consumption, without a substitution effect between fruit provision at school and home fruit consumption.

Finally, chapter 6 discusses the collective findings on the use of food systems approach for healthier outcomes, data gaps in food system research, and research transparency in practice. I also discuss the limitations of the thesis as a whole, such as lacking analyses on synergies and trade-offs within the food systems. This thesis ends with a concise discussion on societal relevance of the studies.