Informing the Design of Large-Scale Food Fortification Programs with Secondary Data: Pilot Results from Nigeria and Zambia.

Background: Large-scale food fortification (LSFF) can improve micronutrient intake, but low-income and middle-income countries often lack resources to collect data for LSFF decision making. We designed a methodology using existing data and methods to inform LSFF programming. Objectives: This study aimed to pilot a methodology using existing diet, market, and diet cost data and assess its implementation feasibility and usefulness for LSFF decision making. Methods: We used household food consumption/availability data from Nigeria and Zambia to assess dietary micronutrient inadequacy and model contributions of LSFF. Market survey (Nigeria) and agrifood information system (Zambia) data were used to estimate availability of fortifiable foods. We used Cost of the Diet software to estimate affordability of an adequate diet in Zambia. We engaged country stakeholders to determine modeling parameters and assess methodology implementation. Results: The analyses took ∼6 mo and cost ∼150,000 USD (Nigeria) and ∼250,000 USD (Zambia). Results showed diets were inadequate to meet vitamin A, folate, and zinc requirements of 32%-67% of households in Nigeria and 51%-83% of households in Zambia. Modeling existing LSFF in Nigeria demonstrated improved micronutrient adequacy of diets, with further improvements possible with rice fortification. In Zambia, existing vitamin A-fortified sugar marginally reduced inadequacy. Introducing mandatory wheat flour and/or maize flour fortification could reduce folate and zinc inadequacies. The market assessment demonstrated widespread availability of fortifiable edible oil, sugar, and wheat flour, but not fortifiable maize flour. The cost of the diet in Zambia with LSFF was similar to the cost without LSFF. Stakeholders found the methodology's components together generated useful, timely evidence for LSFF programming. Conclusions: Our methodology showed opportunities for improving the micronutrient adequacy of diets in Nigeria and Zambia through LSFF. The methodology generated evidence that stakeholders agreed can support LSFF planning. Investments and strategies are needed to strengthen capacity to conduct the assessments, reduce costs, and streamline methods.