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Iron Matters: Absorption and Metabolism

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Iron is an essential element in our daily diet. Most of the iron in our body is used for erythropoiesis, where it is a vital component of haemoglobin. Iron is also critical for growth, development, normal cellular functioning, and synthesis of hormones and connective tissue.

Iron deficiency is the most common type of nutritional deficiency in the world. Diet, some medications, exercise, pregnancy and breastfeeding, and blood loss through menstruation or illness are all factors that can affect iron levels. Iron deficiency is more common in women than men, affecting around one in four women of child-bearing age (particularly during pregnancy and while breastfeeding). Other groups at risk include vegetarians and vegans, frequent blood donors, children and adolescents, and athletes.

Signs and symptoms of iron deficiency include:

  • Fatigue
  • Pale skin
  • Shortness of breath
  • Frequent infections
  • Headache
  • Dizziness or lightheadedness
  • Cold hands and feet
  • Inflammed/sore tongue
  • Brittle nails
  • Fast heartbeat
  • Unusual cravings for non-nutritive substances, such as ice, dirt or starch
  • Poor appetite, especially in infants and children with iron deficiency anemia

Oral iron supplementation is the preferred method of treatment. However, many iron supplements have poor bioavailability and typically produce undesirable adverse effects such as gastrointestinal upset and nausea. 

In this infographic we review the absorption of different types of iron and its utilisation throughout the body. 


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Melissa Lee
Melissa is a designer turned nutritionist, who has combined the two modalities to create purposeful designs for various health publications and websites. Having initially studied Multimedia Systems Design, she then went on to complete a BHSc in Nutritional Medicine which led to her involvement in the integrative medicine industry and eventually to FX Medicine.