We're Currently Accepting New Patients!

The Association Between Mold Illness and Iron Deficiency: A Look at the Mechanisms and Implications

Written by Portland Clinic of Natural Health on September 20, 2023

Iron plays an indispensable role in several physiological processes in the human body, ranging from oxygen transport to DNA synthesis. Unfortunately, it is also an essential nutrient for many pathogenic organisms, including certain fungi. Mold illness, resulting from mold exposure or colonization, has been associated with iron deficiency anemia. The underlying mechanisms involve the fungi's unique ability to extract iron from the host's heme. This article delves into the association between mold illness and iron deficiency, shedding light on the importance of early detection and management.

Molds and Their Need for Iron

Fungi, just like many other microorganisms, require iron for growth and metabolism. However, in the host's environment, free iron is scarce, so fungi have evolved specialized mechanisms to extract it. One such strategy is the use of high-affinity iron uptake systems that can hijack the iron from the host's heme molecules. (1)

Heme, a component of hemoglobin in red blood cells, is rich in iron. Some fungal pathogens possess heme oxygenases or utilize siderophores (molecules that bind iron tightly) to pry the iron away from heme. Once the iron is extracted, it becomes available for fungal metabolic processes, sometimes at the detriment of the host. (2)

Mold Illness and Iron Deficiency Anemia

Iron deficiency anemia is characterized by a reduced number of red blood cells or a lowered hemoglobin concentration due to a lack of iron. It results in symptoms like fatigue, weakness, pallor, and shortness of breath.

Several studies and clinical observations have shown a link between mold illness and iron deficiency anemia. Patients with prolonged mold exposure or mold colonization often present with iron deficiency symptoms. The proposed mechanism is the persistent extraction of iron by molds from the host's heme, leading to reduced iron availability for the synthesis of new red blood cells. (3)

Is it a Direct Causation?

While the association is compelling, it is essential to recognize that correlation does not always imply causation. Iron deficiency anemia in mold illness patients could be due to other underlying conditions, dietary factors, or chronic inflammation. However, the unique iron extraction mechanisms of fungi do provide a plausible pathway for mold-induced iron deficiency.

The relationship between mold illness and iron deficiency anemia underscores the importance of prompt diagnosis and management of mold-related diseases. Recognizing the potential of fungi to deplete iron reserves can guide clinicians in providing comprehensive care to affected individuals. Moreover, the study of fungal iron acquisition mechanisms can pave the way for targeted antifungal therapies in the future.


  1. Philpott CC. Iron uptake in fungi: a system for every source. Biochim Biophys Acta. 2006 Jul;1763(7):636-45. doi: 10.1016/j.bbamcr.2006.05.008. Epub 2006 May 19. PMID: 16806534.
  2. Kornitzer D, Roy U. Pathways of heme utilization in fungi. Biochim Biophys Acta Mol Cell Res. 2020 Nov;1867(11):118817. doi: 10.1016/j.bbamcr.2020.118817. Epub 2020 Aug 8. PMID: 32777371.
  3. Bairwa G, Hee Jung W, Kronstad JW. Iron acquisition in fungal pathogens of humans. Metallomics. 2017 Mar 22;9(3):215-227. doi: 10.1039/c6mt00301j. PMID: 28217776; PMCID: PMC5734051.

Our Newsletter

Experience a New Level of Wellness - Sign Up for the Portland Clinic of Natural Health Newsletter Today!

Related Posts

What our Patients say about us