About 40 % of the population of sub-Saharan Africa (SSA) now live in cities, a percentage that is forecast to rise. Two countries already facing higher rates of urbanisation are South Africa (60 %, Statista South Africa, 2023) and Ghana (50 %, Statista Ghana 2023). At present, the urbanisation rates in South Africa and Ghana are 67·8 % and 58·7 %, respectively^(1,2) . At present, over 70 % of city residents in these countries live in townships or slums – working-class sprawls of formal and informal slum-type housing on the fringes of these urban settlements.

Urbanisation is contributing to changed livelihoods and diets in both rural and urban areas^{(Reference Casari, Di Paola and Banci3,Reference Battersby and Peyton4)} . Poverty levels pre- and post-COVID have remained steady or increased marginally in some areas, while for others poverty rates have risen rapidly, especially during and post-COVID⁽⁵⁾. In addition, rural areas and food systems are being transformed through the penetration of formal retail outlets, often affiliated with international trade and globalisation. Steadily, about half of food imports have composed of cheap ultra-processed foods which are linked to positive changes in weight^{(Reference Dixon and Banwell6,Reference Lin, Teymourian and Tursini7)} . In South Africa and Ghana, the share of the workforce engaged in farming is declining, and rural households are diversifying livelihoods^{(Reference Kuusaana and Eledi8)}. Research in Southern Africa indicates about half of the emerging middle class is rural, and in both urban and rural areas the contribution of purchased and processed foods to overall food expenditure is substantial⁽⁹⁾.

Alongside this rapid urbanisation, modernisation and growing food insecurity has been a ‘nutrition transition’^{(Reference Hawkes, Smith and Jewell10)}. Food insecurity trends in South Africa have consistently declined from 29·3 % in 2002 to 11·1 % in 2019 (pre-COVID) but increased post-COVID – however, the current rates (12·2 %) are still lower than in 2002^{(Reference Stast11)}. In Ghana, there has also been a decline in food insecurity from approximately 13·6 % in the early 2000s to 4·1 % in recent times⁽¹²⁾. South Africa and Ghana are on the same pathway albeit with Ghana on a delayed or slower trajectory. Nutrition transition has created a double burden of malnutrition, in which persisting high rates of stunting and micronutrient deficiencies are now coupled with a rising prevalence of obesity and chronic non-communicable diseases in South Africa and Ghana and increasingly throughout SSA^{(Reference Igumbor, Sanders and Puoane13)}. Women are disproportionately affected both by undernutrition and micronutrient deficiencies that impact on their health and reproductive experiences as well as overweight and obesity which contribute significantly to increasing rates of non-communicable diseases such as diabetes, heart disease and certain female cancers^{(Reference Thow, Sanders and Drury14)}. Key dietary items implicated in the dual burden of malnutrition throughout the developing world are highly processed food products^{(Reference Delobelle, Sanders and Puoane15)}, which tend to have poorer nutritional content – and are more energy dense and higher in salt, fat and/or sugar – than less processed alternatives⁽¹⁶⁾.

The proximal food environment that consumers interact with has a strong influence on decisions and habit formation regarding food purchase and consumption^{(Reference Evans17)}. While research exists that has described and analysed the nutrient content of the diets of South Africans and Ghanaians living in poor socio-economic situations^{(Reference Mchiza, Steyn and Hill18)}, there is a paucity of information about how consumers interact with a changing food environment – and in particular, the relative proportion of food acquired from formal (supermarkets and fast food chains) and informal (spazas and food vendors) outlets, or the relative proportions of unprocessed foods or minimally processed foods, processed culinary ingredients, processed foods and ultra-processed foods^{(Reference Monteiro, Cannon and Moubarac19)}

The sources of food have changed dramatically^{(Reference Kroll, Swart and Annan20)}. Corporate supermarket enterprises are now increasingly dominating food markets – in the case of South Africa, five retail supermarket chains collectively account for between 80 % and 90 % of the formal food retail market in South Africa⁽²¹⁾. Although currently only 30 % of food is purchased in the formal sector in Ghana, foreign retailers view this as a growing market^{(Reference Hawkes, Smith and Jewell10)}.

Production and flows of foods in and into South Africa as well as the number and range of companies involved in manufacturing and retail have recently been examined, in the context of food security and nutrition^{(Reference Thow, Sanders and Drury14)}. However, there is still little known about the nature of the value chains, industry dynamics and policies driving the proximal food environments in peri-urban settings. Although the food environment has a significant impact on both undernutrition and Non Communicable Disease (NCD) risk, the diets of urbanisation and modernising populations in Africa and how they make decisions about food acquisition remain largely unknown. Even more importantly, little is known about the ways in which members of poor and marginalised populations engage with these food environments, and how factors such as income, energy poverty, transport needs, ideological and cultural preferences, gender, perceptions of food quality, nutritional value and status interact to shape consumer choice. Understanding these dynamics between consumers, food environments and food systems can provide insights to inform effective interventions that both support consumers to make healthier food choices and create incentives for healthier food within the food environment. Policies that govern food environments and broader food systems create incentives that influence the price, accessibility and acceptability of healthier foods. These include decisions made by ministries of finance, trade, industry/investment, and agriculture, which interact with food industry dynamics and political considerations regarding food supply and demand. There are many possible policy interventions that can be instituted at municipal, provincial and national government level to regulate and improve the food environment^{(Reference Delobelle, Sanders and Puoane15)}. Some of the effective policies suggested by the World Health Organisation include restricting the advertisement of unhealthy foods and fiscal policies like taxation to reduce the consumption of Sugar Sweetened Beverages (SSB)⁽²²⁾. Yet, with a few notable exceptions (salt regulation and tax on sugary beverages in South Africa; food standards regarding fatty meat in Ghana), very few such policies have been implemented in African countries⁽¹⁶⁾. There is a need both to identify the key policy levers that exist at the level of food systems and value chains to shape the nature of local food environments – and to identify how the agency of poor and vulnerable populations themselves can be effectively engaged in these spaces.

The ROFE study sought to better understand the changing nature of food consumption and value chains and their drivers in SSA within the context of nutrition transition in Africa in order to identify opportunities to align policies across sectors to promote healthy diets and prevent NCD.