Rural−urban built food environment disparities in Kenya: Applying ‘vendor neighbourhood’ as a lens for built food environment characterisation

The food environment offers a strategic entry point for promoting healthier and sustainable diets. However, studies on low- and middle-income countries (LMICs) focus predominantly on rural built food environments and use limited methods for assessing food availability and vendor density. This study developed scalable methodologies to assess built food environments: a novel approach for evaluating vendor neighbourhood-level food availability and vendor density, adjusted for population and area. Research was conducted in two contrasting settings in Kenya: Viwandani ward, an informal urban settlement in Nairobi, and Kiima Kiu ward, a rural setting in Makueni County. A total of 1,192 urban and 894 rural vendors were geocoded and analysed. Food diversity was assessed at the vendor and neighbourhood levels, at distances of 50m, 100m and 200m radii from any given vendor. Urban vendor density was 118 times higher than rural vendor density, but decreased to 114 times after adjusting for population size. While vendor food diversity was higher (p < 0.001) among rural vendors (3.38) than urban vendors (2.58), the vendor neighbourhood food diversity was higher (p<0.001) in the urban (9.16) than in the rural (8.53) built food environment within a 50m radius and beyond. This study highlights the importance of applying population- and area-adjusted density metrics and vendor neighbourhood-level diversity assessments for characterising built food environments in Kenya, typical of LMICs. Our methodological approach provides a replicable framework for guiding policy interventions aimed at improving diet quality through food diversity across both urban and rural settings. • A vendor neighbourhood approach is key for characterising the food environment • Vendor density should be computed in relation to population density • Rural and urban food environment assessments are key to food systems transformation