Food-insecure households interact more frequently with the food environment: food purchase patterns and dietary adequacy in the DECIDE study, Tanzania

This paper examines how food insecurity influences household food purchases and dietary adequacy in the context of a rapidly evolving food environment in Africa. We examine food purchase patterns, nutrient intakes, and food security using data collected in 2019–2020 among people living with HIV in peri-urban Dar es Salaam, Tanzania. Participants reported food purchases and vendor interactions over seven days, evaluated against nutrient intakes from 24-hour diet recalls. Urban food-insecure households interacted more frequently with the food environment than food-secure households, purchasing staples and vegetables more often. Top weekly purchases were tomatoes (62%), sugar (57%), carrots (51%), rice (50%), and maize flour (48%). Staple purchases were associated with lower zinc adequacy (OR: 0.5, P < 0.032), while meat purchase diversity was associated with greater zinc (OR: 1.2, P < 0.039) and vitamin A adequacy (OR: 1.2, P < 0.023). Latent class analysis revealed three distinct weekly purchasing groups: "buy everything," "buy basics," and "purchase sweet and sugary beverages." These groupings were associated with micronutrient adequacy and food security. Informal and semi-formal vendors play a critical role in providing access to nutrient-dense foods across the spectrum of household food security status.