Iron, microbiota and colorectal cancer

Wien Med Wochenschr. 2016 Oct;166(13-14):431-436. doi: 10.1007/s10354-016-0508-4. Epub 2016 Aug 30.


Iron deficiency and anaemia are common in colorectal cancer. Replacement with oral or intravenous iron effectively treats this deficiency. However, mechanistic and population studies suggest that excess iron promotes colorectal carcinogenesis. Growing research into gut microbiota and dysbiosis suggests one explanation for this association. Iron is growth limiting for many pathogenic bacteria and may promote a shift in the ratio of pathogenic to protective bacteria. This may increase the toxic bacterial metabolites, promoting inflammation and carcinogenesis. This has important implications as we seek to correct anaemia in our patients.

Keywords: Anaemia; Carcinogenesis; Colorectal cancer; Dysbiosis; Iron deficiency.

Publication types

  • Review

MeSH terms

  • Anemia, Iron-Deficiency / drug therapy*
  • Anemia, Iron-Deficiency / physiopathology*
  • Carcinogenesis / chemically induced
  • Colorectal Neoplasms / chemically induced*
  • Colorectal Neoplasms / physiopathology*
  • Dose-Response Relationship, Drug
  • Dysbiosis / chemically induced*
  • Dysbiosis / physiopathology*
  • Gastrointestinal Microbiome / drug effects*
  • Gastrointestinal Microbiome / physiology*
  • Humans
  • Iron / administration & dosage*
  • Iron / adverse effects*
  • Risk Factors


  • Iron