The epidemiology and drivers of healthy, sustainable diets in Sub-Saharan Africa

Background: The food environment in sub-Saharan Africa (SSA) has transformed rapidly in recent decades to increase the availability of unhealthy food options. Dietary changes are significantly contributing to adverse environmental impacts and a rapidly increasing burden of obesity and diet-related noncommunicable diseases (NCDs) co-existing with unresolved undernutrition and communicable disease prevalence. Trends in the consumption of foods, the characteristics of the prevailing food environment, and how individuals interact with their food environment to contribute to the double malnutrition burden in SSA are less understood. The aims of this PhD were to examine secular trends in consumption of food groups important for health in SSA; examine the food environment characteristics in a case study elite urban community in Ghana; investigate how residents of the urban community interact with their food environment to shape dietary behaviours; and explore their willingness and attitudes towards the adoption of healthy and sustainable diets. Methods: A mixed methods approach was adopted as follows: (1) evidence synthesis of literature reporting meat, fruit, and vegetable (MFV) consumption in SSA and (2) of literature reporting ultra-processed foods consumption in SSA; (3) Geographic Information Systems (GIS) tools were used to collect data on the characteristics of the food environment within University of Ghana campus including the location, count, and distribution of food outlets. An adapted food classification tool was utilized to categorise outlets as NCD-health, NCD-intermediate or NCD-unhealthy; and (4) qualitative focus group discussions (FGDs) and dyadic interviews with best friend pairs (or best friend pair interviews-BFPIs) were used to collect students' perspectives of their interaction with their food environment and how it impacts their dietary practices. The FGDs and BFPIs also gathered students' attitudes to dietary change in relation to health and environmental sustainability. Results: Study components 1 and 2 highlighted that MFV consumption has seen upward trends in SSA populations over the last 38-year period between 1977 and 2015, although fruit and vegetable consumption remain significantly below WHO recommendations. Richer SSA countries are consuming more meat (ß =36.76, p=0.04) and vegetable (ß =43.49, p=0.00) than poorer countries. Further, it suggested that ultra-processed foods (UPFs) consumption in SSA populations has gone up and highlighted key gaps in the UPFs consumption literature in SSA. Urban residents and females appeared to be consuming more UPFs than rural dwellers and males. Study 3 showed that the characteristics of the food environment is suggestive of an obesogenic one, dominated by more NCD-unhealthy than NCD-healthy food-outlets (50.72% vs 39.86%). Food outlets were unevenly distributed over the university foodscape, with more NCD-unhealthy outlets clustering closer to residential than departmental buildings. This difference was statistically significant for food outlets within 100-meter buffer (p=0.00) of residential structures and those within 100 and 500 meters from departmental buildings/lecture halls (p=0.05 and p=0.00, respectively). Study component 4 (n=46) identified a complex interplay of individual and social level factors interacting with food environment characteristics to shape dietary behaviours. Conclusion: The findings of this thesis provide detailed understanding of trends in consumption of food groups important for health and the environmental sustainability in Sub-Saharan Africa. It also provides in-depth understanding of how young adults interact with their food environment and how the food environment influences dietary behaviours, which could be used to inform context and culturally specific interventions.