Iron is vital for the production of red blood cells and is the most common nutritional deficiency worldwide, both in developed and developing countries

Broccoli is an excellent source of iron.

 

Iron is vital for the production of red blood cells and is the most common nutritional deficiency worldwide, both in developed and developing countries.

As it participates in a wide variety of metabolic processes, including oxygen transport, deoxyribonucleic acid (DNA) synthesis, and electron transport, a constant balance between iron uptake, transport, storage, and utilisation is required to maintain iron homeostasis.

The prevalence of iron deficiency is highest among young children and women of childbearing age (particularly pregnant women). In children, iron deficiency causes developmental delays and behavioural disturbances, and in pregnant women, it increases the risk for a preterm delivery and delivering a low-birthweight baby. According to the Center for Disease Control (CDC), in the past three decades, increased iron intake among infants has resulted in a decline in childhood iron-deficiency anaemia in the United States, however iron deficiency has remained prevalent in women of childbearing age.

Signs and symptoms

Patients with iron deficiency anaemia may report the following:

  • Fatigue and diminished capability to perform hard labour
  • Leg cramps on climbing stairs
  • Craving ice (in some cases, cold celery or other cold vegetables) to suck or chew
  • Poor scholastic performance
  • Cold intolerance
  • Reduced resistance to infection
  • Altered behaviour (e.g. attention deficit disorder)
  • Dysphagia with solid foods (from oesophageal webbing)
  • Worsened symptoms of comorbid cardiac or pulmonary disease

Risk factors

  • Black women have a lower mean haemoglobin and a wider standard deviation than white women, even after adjustment for iron status
  • Blood donation more than two units per year in women and three units per year in men
  • Low socioeconomic status and postpartum status
  • Child and adolescent obesity
  • Child: BMI ≥ 85% and < 95% percentile
  • Adolescent: BMI ≥ 95% percentile
  • Vegetarian diet: 40% of vegans 19-50 years of age are iron deficient

Although there is consensus that the objective of successful treatment of iron-deficiency anaemia is the adequate and quick supply of iron to increase haemoglobin levels to normal values within 4-6 weeks and to replenish iron stores, the route of iron administration is still a matter of debate. That said, cheap, safe, and effective at correcting iron deficiency anaemia, oral iron therapy is usually the first-line therapy for patients with IDA.

Fast facts

  • The prevalence of iron deficiency anaemia is 2% in adult men
  • Nine% of patients older than 65 years with iron deficiency anaemia have gastrointestinal cancer when evaluated
  • In children, adolescents, and women of reproductive age, a trial of iron is a reasonable approach if the review of symptoms, history, and physical examination are negative; however, the haemoglobin should be checked at one month
  • Iron metabolism is unusual in that it is controlled by absorption rather than excretion. Iron is only lost through blood loss or loss of cells as they slough
  • Men and non-menstruating women lose about 1mg of iron per day. Menstruating women lose from 0.6 to 2.5% more per day
  • Dietary iron is available in two forms: heme iron, which is found in meat; and nonheme iron, which is found in plant and dairy foods
  • Iron deficiency results when iron demand by the body is not met by iron absorption from the diet. Thus, patients with IDA presenting in primary care may have inadequate dietary intake, hampered absorption, or physiologic losses in a woman of reproductive age
  • IDA is never an end diagnosis; the work-up is not complete until the reason for IDA is known