Iron Release from Lucky Iron Fish® Across pH Levels and Acidification Treatments: Effects Relevant to Food Fortification

Rachel Meek¹, Steven McGeehan^{2, 3} and Kathy Beerman^3,

¹General Dentistry, Morita Dentistry, Bellevue, WA, United States

²College of Agricultural and Life Sciences; Laboratory Director Analytical Sciences Laboratory, University of Idaho, Moscow, ID, United States

³School of Biological Sciences, Washington State University, Pullman, WA, United States

Cite this paper:
Rachel Meek, Steven McGeehan and Kathy Beerman. Iron Release from Lucky Iron Fish® Across pH Levels and Acidification Treatments: Effects Relevant to Food Fortification. World Journal of Nutrition and Health. 2025; 12(1):16-22. doi: 10.12691/jnh-12-1-3

Abstract

Iron deficiency anemia (IDA) is a critical public health issue in populations living in resource-limited regions of the world. While iron-rich diets and iron supplementation can reverse IDA, settings characterized by economic hardship and limited access to nutritious foods may require more practical, sustainable approaches. The Lucky Iron Fish (LIF), an iron ingot used in cooking, has been shown to improve iron status. Iron release from LIF is influenced by pH and boiling time, but the impact of different acidifying agents at varying pH levels remains unclear. Thus, optimum acidification and cooking methods to maximize iron enrichment of food have not been determined. This study evaluated the effects of water acidification treatments and pH levels on iron release from LIF and its ability to fortify black beans and white rice. Experiments, conducted in triplicate, used acetic acid, ascorbic acid, and lemon juice at pH levels 4.0, 4.5, 5.0, and 5.5. Foods were cooked with iron-fortified water using non-fortified tap water as a control. Total iron concentrations were measured for both aqueous and food samples. The results show aqueous iron concentrations significantly increased as pH decreased for all acid treatments, but only minor differences were found when acid types were compared. Using acetic acid (pH 4.5) as the acidification treatment, the iron content of both black beans and white rice doubled compared to the control. The iron content of black beans nearly tripled when pre-soaked in iron-fortified water prior to cooking in iron-fortified water. These results suggest that proper acidification and cooking preparation methods can enhance iron fortification of black beans and rice, both of which are staple foods in many regions of the world. Fortifying food with iron using the LIF provides a straightforward, affordable strategy that could have a significant global impact in preventing and treating IDA.

Keywords:
Iron deficiency anemia Lucky Iron Fish Iron fortification of food

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