Iron Deficiency Anaemia

Overview

Iron deficiency anaemia (IDA) is the most prevalent nutritional deficiency worldwide, affecting approximately 30% of the global population, particularly young children and premenopausal women. Iron is vital for critical biological processes, including oxygen transport, energy metabolism, DNA synthesis, and cell proliferation. Iron deficiency, a precursor to IDA, occurs when iron stores are depleted without necessarily progressing to anaemia. When iron deficiency advances to IDA, it results in microcytic hypochromic anaemia, characterized by small, pale red blood cells due to insufficient iron for haemoglobin synthesis.

Symptoms

IDA presents with a range of symptoms that can significantly impact quality of life. Common symptoms include: Impaired work capacity and cognition, restless legs syndrome, cracking at the corners of the mouth, craving and consumption of non-nutritive substances such as clay, dirt, or paper (pica).

Causes

Iron deficiency can result from insufficient dietary iron, poor absorption, excessive iron loss, or a mix of these factors. Those most at risk include infants, children, pregnant women, and women of childbearing age with heavy menstrual bleeding due to their high iron needs.

For pregnant women, low iron-rich food intake, short intervals between pregnancies, and obesity are significant contributors. Additional risks for women with heavy menstrual bleeding include low consumption of meat, recent blood donations, nosebleeds, and low body mass index

Risk Factors

Several factors predispose individuals to IDA:

• Inadequate Dietary Intake: Low consumption of iron-rich foods.

• Heavy Menstrual Bleeding: Significant blood loss in premenopausal women.

• Chronic Blood Loss: Common in older adults due to gastrointestinal issues.

• Medication Use: Drugs like NSAIDs that may cause bleeding.

• Chronic Kidney Disease: Impaired erythropoiesis and iron metabolism.

• Obesity: Emerging evidence suggests a link, though the mechanism is not fully understood.

Inhibitors of Iron

Certain components within food such as polyphenols, calcium, phytates, and inositol bind to iron reducing its absorption and bioavailability. Main sources of such inhibitors include tea, coffee, milk and milk products, bran cereals, legumes, nuts, and seeds. Vitamin C intake with these foods improves iron absorption.

Enhances of Iron Absorption

Enhancers of iron absorption include:

• Haem iron, present in meat, fish, poultry, and seafood

• Ascorbic acid or vitamin C, present in fruits, juices etc.

Treatment

Once IDA is confirmed, oral iron supplementation is the first-line treatment to improve quality of life. Key considerations include:

• Dietary Iron Sources: Heme iron (found in red meat, poultry, fish, and seafood) has higher bioavailability than non-heme iron (from plant-based sources). Consuming vitamin C-rich foods enhances non-heme iron absorption.

• Oral Iron Supplements: These are cost-effective but may cause side effects such as constipation, nausea, vomiting, or diarrhoea. Slow-release formulations or taking supplements with food can mitigate these effects.

• Monitoring and Follow-Up: If oral supplementation is ineffective, the underlying cause of IDA must be re-evaluated. Intravenous iron or further diagnostic workup may be necessary.

• Precaution: Patients should consult a healthcare provider before starting iron supplements to avoid inappropriate use, particularly if the cause of deficiency is unclear.