Iron deficiency anaemia occurs when your body does not have enough iron to make a protein called haemoglobin, which is carried in your red blood cells and transports oxygen around your body. 2
Iron deficiency anaemia
Iron deficiency anaemia refers to the lack of iron in your body, which impacts your ability to make haemoglobin and transport oxygen around your body.
Iron deficiency anaemia can occur in the following ways: 4
- Blood loss – as a result of surgery or internal bleeding.1 Women with heavy menstruation (blood loss due to periods), pregnant women and those post childbirth can become iron deficent. 6
- Poor iron absorption – disorders such as Crohn’s Disease or Coeliac disease can reduce your body’s ability to absorb iron from the gut. 4
- Inadequate dietary iron intake – vegetarian and vegan lifestyles can have an increased risk for iron deficiency due to the reduced intake of animal products rich in easily absorbable iron. 4
Additional causes and risk factors for iron deficiency anaemia in people with cancer include:
- Certain cancer treatments such as radiation therapy, as well as some chemotherapy drugs can damage bone marrow tissue where blood cells are made. They can also damage the kidneys, where a hormone (erythropoietin) is made, which helps make the red blood cells in the bone marrow.1
- Certain types of cancers – such as bowel cancers (which can cause iron deficiency by chronic blood loss into the gut), blood/bone marrow cancers and cancers that spread to the bone marrow.1
- Side effects of cancer and its treatment – these can often cause vomiting and nausea and poor appetite, which can result in low levels of iron in the diet.1
Some people with mild iron deficiency anaemia may not notice symptoms straight away, however typical signs and symptoms include: 5,6
- Pale and washed-out looking skin
- Tiredness and feeling weak
- Dizziness and feeling faint
- Difficulty catching your breath
- Pain in your chest
- Irregular heart beat
- Cold hands and feet
- Pica – this is a craving for things that are not food such as dirt or paint.
It is important to see your doctor if you are experiencing any of the above symptoms.
Anaemia is diagnosed through a blood test, known as a full blood count. To document iron deficiency, a blood test referred to as “iron studies” will be required. This test will include a serum ferritin (the amount of total iron you have stored in your body), which will generally be low in iron deficiency.7
The World Health Organisation defines anaemia as a haemoglobin level below 130g/L for men and 120g/L for non-pregnant women and iron deficiency as a serum ferritin below 30mcg/L for all adults.7
In people with chronic illness, such as cancer, ferritin levels can rise because of the effect of illness or inflammation, therefore additional tests may be required to confirm a diagnosis of iron deficiency anaemia in these circumstances.7
The aim of treatment is to normalise the haemoglobin level and replenish the iron stores in your body. This can be done though the following ways: 4,6
- Taking oral iron supplements
- Iron infusion – where iron is given intravenously (via a needle into your blood vessel)
- Red blood cell transfusion – for more serious cases of iron deficiency anaemia
Increasing iron-rich sources in the diet such as lean red meat can help, but it is unlikely to restore iron levels adequately without additional treatment when anaemia is present.
An important part of the management of iron deficiency anaemia is to address the cause of the problem i.e. stop blood loss for example.
Additional testing may also be required to understand the cause of the iron deficiency anaemia, such as testing for gastrointestinal bleeding.6
Iron and haemoglobin are not the same thing. Haemoglobin is a protein that is responsible for transporting oxygen around your body. Iron is a mineral that you obtain through your diet. Iron is essential for making haemoglobin, and it gives your blood cells (and haemoglobin) their red colour.
In the diet there are two sources of iron, known as haem-iron (these come from animal-based foods) and non-haem iron (these come from plant-based foods). Animal-based sources (such as lean beef and lamb, chicken and eggs) of iron are more easily absorbed by your body, compared with plant-based sources (green leafy vegetables, nuts, seeds and fortified cereals).8
Including foods rich in vitamin C (such as kiwifruit) in your diet may help increase your body’s ability to absorb iron. Avoiding foods rich in calcium (such as milk) as well as caffeine when eating iron-rich foods can also be helpful, as these stop iron from being absorbed in your body.
- American Society for Clinical Oncology (ASCO).(2019). Anaemia. Retrieved on 12th June 2019 from https://www.cancer.net/coping-with-cancer/physical-emotional-and-social-effects-cancer/managing-physical-side-effects/anemia
- NIH: National Heart, Lung and Blood Institute. (2011). In brief: your guide to anaemia. Retrieved on 12th June 2019 from https://www.nhlbi.nih.gov/files/docs/public/blood/anemia-inbrief_yg.pdf
- American Cancer Society. (2017). Anaemia in people with cancer. Retrieved on 12th June 2019 from https://www.cancer.org/treatment/treatments-and-side-effects/physical-side-effects/low-blood-counts/anemia.html
- Gastroenterological Society of Australia (GESA). (2015). Iron Deficiency. Retrieved on 13th June 2019 from http://cart.gesa.org.au/membes/files/Clinical%20Guidelines%20and%20Updates/Iron_Deficiency_2015.pdf
- Australian Red Cross Blood Service. (n.d). Iron Deficiency Anaemia. Retrieved on 14th June 2019 from https://mytransfusion.com.au/reasons-transfusion/iron-deficiency
- NIH: National Heart, Lung and Blood Institute. (n.d). Iron Deficiency Anaemia. Retrieved on 14th June 2019 from https://www.nhlbi.nih.gov/health-topics/iron-deficiency-anemia
- Australian Red Cross Blood Service. (2017). Diagnosis and investigation of iron deficiency anaemia. Retrieved on 14th June 2019 from https://transfusion.com.au/transfusion_practice/anaemia_management/iron_deficiency_anaemia/diagnosis_and_investigation
- Dietitians Association of Australia. (n.d). Anaemia: my doctor says I need more iron. Retrieved on 12th June 2019 from https://daa.asn.au/smart-eating-for-you/smart-eating-fast-facts/nourishing-nutrients/anaemia-my-doctor-says-i-need-more-iron/