Nationally Representative Estimates of the Cost of Adequate Diets, Nutrient Level Drivers, and Policy Options for Households in Rural Malawi

A growing literature uses the cost of diets to evaluate how effectively a food system supports access to nutritious foods. We identify baseline levels, nutrient drivers, and potential policy-induced changes in the feasibility and cost of meeting nutrient requirements for whole households based on aggregate needs in rural Malawi from 2013 – 2017. We determine the availability and cost of a nutrient-adequate diet each month using the price and composition of foods available at the nearest market. We run more than 1 million models in total, one for every household in each month under baseline and eight policy simulation scenarios. We find diets containing adequate nutrients for whole families to be available 60% of the time from 2013–2017, and when available, costing an average $2.32/person/day (2011 US$ PPP). Further, we illustrate that as households grow in size and diversity of member types, the cost to acquire 1,000 calories of a sufficiently nutrient dense diet increases. Our policy simulations reveal that selenium is the nutrient hindering the availability of diets adequate and balanced in essential nutrients, but that riboflavin is the costliest nutrient to obtain in the market when a least-cost diet is available. We estimate selenium soil biofortification of maize would result in nearly universally available (94%) adequate diets at half the cost ($1.22/person/day on average). This far exceeds the potential impact of price or availability changes of foods dense in the costliest nutrients including eggs, milk, groundnuts, and dried fish. No other scenario improves availability or exceeds 1% average cost reduction. Of direct relevance to agriculture and nutrition policy in Malawi, this study demonstrates how the availability and cost of whole diets and the shad-ow prices of individual nutrients in retail markets can be used to identify barriers to accessing an adequate diet and estimate the potential impacts of policy options