https://pubmed.ncbi.nlm.nih.gov/38222205/

Background: Iron deficiency is a critical global health issue. One of the intriguing manifestations linked to iron deficiency is the presence of pica. The physiological relationship between the senses of smell and taste suggests that pica may be accompanied by an inclination towards the smell of earth (geosmin). The smell of geosmin is distinct and generally recognized as a pleasing scent

Conclusion: In iron deficiency patients, geosminophilia and the presence of pica may accompany each other. Therefore, geosminophilia has the potential to be a new symptom of iron deficiency.