What Is Iron?

Iron is essential nutrient which is needed to form the protein, haemoglobin in red blood cells. Haemoglobin consists of four chains which contain a haem group and present in each haem group is iron. Haemoglobin is essential for the transportation of oxygen around the body. Low levels of iron can lead to iron deficiency anaemia while high levels of iron can be toxic.[1]

What Role Does It Play in The Body?

Iron’s key role in the body is to help produce healthy red blood cells. The human body requires iron to produce haemoglobin – an oxygen transporter. Approximately 2/3 of iron in the body is found in the haemoglobin of circulating red blood cells, while a quarter of iron is stored, and the rest is bound to proteins in muscle tissue as well as being present in enzymes needed for cellular functions.[2]

Iron is recycled within the body as there is no mechanism for excretion of iron except for bleeding such as trauma, pregnancy and menstruation. The amount of iron absorbed from the amount which is eaten is relatively low, so dietary intake and optimum absorption are key. There are two types of dietary iron: haem iron (from meat and fish sources) and non-haem iron (from plant-based sources).2

How Does Iron Affect My Wellbeing?

Too much and too little iron can have negative health consequences on the human body. Inherited conditions such as hereditary haemochromatosis cause an inappropriately increased absorption of iron which can lead to iron accumulation within tissues and potential organ damage. The liver is the organ which is predominantly affected as well as the heart, skin, pituitary gland, joints and pancreas. Symptoms can include hyperpigmentation of the skin, joint pain, arthritis, diabetes, liver cirrhosis and inflammation. Other causes of high iron levels include iron overload which may result from excessive blood transfusions. In early life, iron overload can lead to growth failure and the inability of the thyroid gland to function properly. The central nervous system can also be affected by iron overload and is usually found alongside conditions such as Alzheimer’s Disease and Huntington’s Disease. Iron overload is also associated with a higher risk of developing cancer.[3]

Low levels of circulating iron, on the other hand, can lead to iron deficiency anaemia. Low levels can be caused by:

  • Not consuming enough dietary iron
  • The inability of the body to absorb iron
  • An increased need for iron e.g. pregnancy, peptic ulcer or colon cancer

During the early stages of iron deficiency anaemia, there may be no physical symptoms. However, as the condition progresses/worsens signs may include:

  • Extreme fatigue
  • Weakness
  • Pale skin
  • Brittle nails and hair
  • Headaches
  • Dizziness
  • Light-headedness
  • Sore or inflamed tongue
  • Difficulty breathing[4]

How Can I Improve My Result?

Your iron status can be improved or maintained with diet and adequate exercise.


Good sources of dietary iron include:

Haem iron:

  • Red meat – beef, lamb and pork
  • Fish
  • Poultry

Non-Haem Iron

  • Dark green leafy vegetables – spinach, cabbage and broccoli
  • Nuts
  • Seeds
  • Pulses[5]

Plant-based sources of iron such as dark green leafy vegetables, nuts, seed, pulses and fortified cereals may be absorbed better in the presence of vitamin C.[6] Try eating fortified breakfast cereals alongside a glass of orange juice or swap chips for a jacket potato with a side of green leafy veg – be sure to eat the skin of the potato.

You should also refrain from drinking tea with your meals as this can affect iron absorption. Instead, you should drink it between meals to ensure you absorb iron effectively.[7]

Women who are menstruating or pregnant may need to increase their iron intake. During your period you lose blood which contains vital iron and you should look to replace this through dietary sources or supplements.


Both too much and too little iron can influence energy levels and could affect your ability to exercise. Low iron can also influence how well and quickly your muscles repair themselves after exercise.[8] Iron deficiency anaemia may also be more common in athletic groups and may need iron supplementation.

You can track your Ferritin level through a simple at home finger prick blood test.



[1] The Open University. (2017). Nutrition: Vitamins and Minerals. The Open University.

[2] Abbaspour, N., Hurrell, R and Kelishadi, R. (2014). Review on Iron and its Importance for Human Health. Journal of Research in Medical Sciences: 19(2), pp 164-174.

[3] Papanikolaou, G and Pantopoulos, K. (2004). Iron Metabolism and Toxicity. Toxicology and Applied Pharmacology: 202, pp 199-211

[4] Lopez, A., Cacoub, P., Macdougall, I, C and Peyrin-Biroulet, L. (2015). Iron Deficiency Anaemia. The Lancet

[5] British Dietetic Association. (2017). Food Fact Sheet: Iron. Available at: https://www.bda.uk.com/foodfacts/iron_food_fact_sheet.pdf

[6] Lane, D, J, R and Richardson, D, R. (2014). The Active Role of Vitamin C in Mammalian Iron Metabolism: Much More than Just Enhanced Iron Absorption. Free Radical Biology and Medicine: 75, pp 69-83.

[7] Zijp, I, M., Korver, O and Tijburg, L, B, M. (2000). Effect of Tea and Other Dietary Factors on Iron Absorption. Critical Reviews in Food Science and Nutrition: 40(5), pp 371-398.

[8] Beard, J and Tobin, B. (2000). Iron Status and Exercise. The American Journal of Clinical Nutrition: 72(2), pp 594S-597S.