Nationally representative estimates of the cost of adequate diets, nutrient level drivers, and policy options for households in rural Malawi

•Malawi’s food system is currently unable to reliably facilitate access to nutrient-adequate diets for rural families.•Larger households eating shared meals face greater constraints.•Several nutrients drive the observed high cost: riboflavin, B12, copper, and selenium.•Selenium soil biofortification of maize can make adequate diets near-universally feasible at half the cost.•Policy scenario and least-cost diet modeling can identify barriers and opportunities to accessing nutritious diets for all.