By: Dr. Adam McLeod, ND, BSc
Everyone has seen a someone with cancer who looks pale and depleted with energy. This is often due to anemia which means that there are less red blood cells to transport oxygen to tissues in the body. There are a number of different potential causes for this and one of the most common causes is low iron. When a doctor looks at blood work that clearly says “low iron” there is often an immediate response to supplement the patient with iron. However, we should not be so quick to prescribe iron to every cancer patient that is showing signs of anemia.
The interactions between iron and cancer are very complex and altered iron metabolism is considered a key metabolic “hallmark of cancer”(1). It is clear that iron has roles in all aspects of cancer development, including the tumour microenvironment and metastasis. As evidenced by the expression pattern of ‘iron genes’ in malignant tumours, it is not simply associated with cancer, but also is indicative of a patient’s chances of survival(2).
Our bodies have evolved to tightly partition and limit the amount of available iron. The iron deficiency anemia that is observed in cancer patients may actually be the bodies response to the presence of cancer. By limiting the availability of iron in circulation, there is less available for the cancer to utilize. If the patient is given iron then you are essentially fighting against the bodies effort to lower the iron levels.
There are a number of different studies that clearly show a strong connection between low iron levels and decreased cancer risk. It is well documented that people who regularly donate blood have lower rates of developing cancer(3). This is likely connected to decreased iron levels following donation of blood. A popular natural cancer therapy called curcumin, acts as a potent natural chelator of iron(5). It is thought that some of the observed anti-cancer properties might be due to the fact that it powerfully sequesters iron away from cancer cells(6).
Recent research indicates that tumours create their own iron-rich micro-environment to evade constraints that are imposed by limited systemic iron availability. Cancer cells will sequester iron and it is possible that this allows the cancer cells to mutate more quickly. Iron reacts with oxygen to produce free radicals that damage DNA. Normally this is not desirable, however, this allows cancer cells to adapt more quickly to different conditions when the DNA is being constantly damaged on a low level. This consistent damage from excess iron is thought to increase the mutation rate of the DNA within the cancer cells. This recent evidence for regulation of iron in the tumour micro-environment represents a new paradigm in iron biology(4).
Of course there are some situations where iron must be prescribed but it should not be done unnecessarily. Many effective cancer therapies work by actually decreasing the level of iron in the blood. If the red blood cells are reduced in number and smaller than normal (low MCV) then you very likely have iron deficiency anemia. It is very important to also check the level of ferritin to check on your bodies ability to transport iron. A Naturopathic doctor that works with oncology will take the time to look at your case and will write you a prescription for iron if it is truly indicated.
Dr. Adam McLeod is a Naturopathic Doctor (ND), BSc. (Hon) Molecular biology, First Nations Healer, Motivational Speaker and International Best Selling Author. He currently practices at his clinic in Vancouver, British Columbia where he focuses on integrative oncology. http://www.yaletownnaturopathic.com
1) Hanahan D, Weinberg RA. Hallmarks of cancer: the next generation. Cell. 2011;144:646–674. [PubMed]
2) Miller LD, et al. An iron regulatory gene signature predicts outcome in breast cancer. Cancer Res. 2011;71:6728–6737. [PMC free article]
3) Edgren G, et al. Donation frequency, iron loss, and risk of cancer among blood donors. J. Natl Cancer Inst. 2008;100:572–579. [PubMed]
4) Torti, Suzy V., and Frank M. Torti. “Iron and cancer: more ore to be mined.” Nature Reviews Cancer 13.5 (2013): 342-355.
5) Jiao Y, et al. Iron chelation in the biological activity of curcumin. Free Radic. Biol. Med. 2006;40:1152–1160. [PubMed]
6) Jiao Y, et al. Curcumin, a cancer chemopreventive and chemotherapeutic agent, is a biologically active iron chelator. Blood. 2009;113:462–469. [PMC free article]