INTRODUCTION:
This modeling study investigates whether fortification can reduce the environmental footprint and cost of food consumption among Iranian adult men, while providing key micronutrients typically found in animal sources, such as calcium, vitamin D, iron, and zinc.

METHODS:
Based on adjusted household expenditure and income data for adult men, three scenarios were constructed: No fortification, voluntary fortification, and mandatory fortification. Linear programming was used to calculate at what calorie levels, water footprint, carbon footprint, and cost, the four micronutrients could be nutritionally provided, at constraints of adhering to Iranian food-based dietary guidelines and cultural acceptability.

RESULTS:
In 12 linear programming models, mandatory fortification reduced the water footprint by 19% and the cost by 11% compared to the baseline, without causing a reduction in the carbon footprint, despite lower calorie content. Trends were almost constant for micronutrients, with mandatory fortification outperforming voluntary fortification. Cereals, fats, sugars, and the miscellaneous food group decreased (-28 to -83%), while fruits (+21 to +60%) and dairy (+107 to +330%) increased; vegetables showed no integrated trend, and total protein sources decreased without preferential reduction in animal-based sources.

CONCLUSIONS:
Food fortification is emerging as a policy tool to promote sustainable food systems in Iran, reduce water footprints in the face of water scarcity, and improve affordability for food security. The future of fortified foods could enhance environmental and economic benefits beyond this study and align with Sustainable Development Goals 2 (Zero Hunger), 6 (clean water and sanitation for all), and 12 (responsible consumption and production).