The effectiveness of iron ingots in iron deficiency anemia treatment: a systematic review

Worldwide, anemia impacts 40% of children aged 6 to 59 months and 30% of reproductive-aged women; about half of these cases are due to iron deficiency (IDA). Iron ingots are inexpensive, lightweight, and easy-to-use IDA treatments. This systematic review assessed the effect of iron ingots on IDA and described variability in iron ingot use. We included studies that evaluated the effectiveness of iron ingots for dietary iron supplementation and described ingot use conditions. Our search yielded 106 articles, 10 of which met inclusion criteria. Multiple authors independently performed data extraction and quality assessment. Four articles were laboratory-based, and five were community trials, and one was both. Acidic conditions, longer cooking durations, and simultaneous use of multiple ingots were associated with higher concentrations of iron leaching. Four studies reported increased hemoglobin levels with ingot use. Notably, studies differed on ingot use instructions, study design, and adherence measurement. The factors that might influence iron ingot effectiveness have not been consistently reported. We recommend that studies provide explicit instructions on ingot use, assess adherence, and investigate contextually relevant conditions to maximize ingot effectiveness in community settings.