Iron Deficiency Anaemia — NZ Condition Guide | KiwiMeds

What is Iron Deficiency Anaemia?

Iron deficiency anaemia is the most common nutritional deficiency worldwide and one of the most common conditions managed in New Zealand general practice. It occurs when the body does not have enough iron to produce haemoglobin — the protein in red blood cells that carries oxygen around the body.

Overview

Symptoms include fatigue and weakness, pale skin, shortness of breath, headaches, dizziness, cold hands and feet, brittle nails, hair loss, unusual cravings for non-food substances (pica — e.g. ice, dirt), and a sore or swollen tongue. Symptoms often develop gradually and can be attributed to other causes. Iron deficiency anaemia is most common in women of reproductive age (due to menstrual blood loss), pregnant women, young children, and people with chronic conditions affecting absorption.

Treatment in New Zealand

Treatment involves identifying and addressing the underlying cause of iron deficiency (e.g. heavy periods, bowel disease, dietary insufficiency) and replenishing iron stores. Oral iron supplements (ferrous sulphate or ferrous fumarate — funded by Pharmac) are the standard first-line treatment, taken with water or orange juice (vitamin C enhances absorption) on an empty stomach if tolerated. IV iron infusions are used when oral iron is not tolerated or absorbed. Dietary sources of iron include red meat, chicken, fish, legumes, tofu, and fortified cereals.

NZ-Specific Information

Iron supplements are funded by Pharmac on prescription. Free dietitian support is available through GPs for dietary management. Ferritin (a marker of iron stores) and full blood count are the key monitoring tests. Blood tests for iron deficiency are fully funded through community labs.

Frequently Asked Questions

Can I get enough iron from my diet? Many people can maintain iron levels through diet, but those with high needs (pregnant women, heavy periods, vegans) may need supplements. Why do iron tablets cause constipation? Iron can slow gut motility, causing constipation and dark stools. Taking iron every other day rather than daily may improve tolerance. How long does it take to correct iron deficiency? Usually 3–6 months of supplementation to replenish stores, even after haemoglobin normalises.

Supplements That May Support Management

⚠️ Important: The supplements listed below have varying levels of clinical evidence. They are not a substitute for prescribed medications and should only be considered as adjunctive support under the guidance of a qualified healthcare professional. Always inform your GP or pharmacist before commencing any supplement, as interactions with prescribed medicines are possible.

• Ferrous Sulphate (Iron Supplement) — Ferrous sulphate (65 mg elemental iron, taken as 200 mg ferrous sulphate) is the standard first-line iron supplementation for iron deficiency anaemia. Taken on an empty stomach with vitamin C maximises absorption. Alternate-day dosing (every other day) has emerging evidence for equivalent efficacy with fewer gastrointestinal side effects than daily dosing.
• Ferrous Gluconate or Bisglycinate (better tolerated alternatives) — For those who experience significant gastrointestinal side effects from ferrous sulphate, ferrous gluconate and ferrous bisglycinate provide equivalent iron with fewer GI effects and are appropriate alternatives.
• Vitamin C (co-administration) — Vitamin C (100–200 mg) taken simultaneously with iron supplements significantly enhances non-haem iron absorption by reducing ferric to ferrous iron in the gut and preventing the formation of insoluble iron complexes.
• B12 and Folate — Iron deficiency anaemia commonly co-exists with B12 and folate deficiency, particularly in malabsorption conditions (coeliac disease, IBD) or poor dietary intake. A full blood count and iron studies should include B12 and folate assessment.

Relevant Vaccinations

Individuals living with iron deficiency anaemia may benefit from the following vaccinations. Please discuss your vaccination status with your GP or practice nurse, as eligibility and funding through the New Zealand National Immunisation Schedule may apply.

• Influenza (annual) — Iron deficiency impairs immune function, increasing susceptibility to infections. Annual influenza vaccination is particularly beneficial.
• COVID-19 — Impaired immune competence from iron deficiency is associated with worse infection outcomes. Maintaining vaccination is recommended.

Dietary Guidance

Evidence-based dietary modifications play a meaningful role in the management of iron deficiency anaemia. The following foods are generally recommended as part of a balanced, condition-appropriate diet. A referral to a registered dietitian may be beneficial for personalised nutritional planning.

• Haem iron foods (red meat, liver, lamb, poultry, fish) — Haem iron from animal sources is the most bioavailable dietary iron form (15–35% absorption). Lean red meat consumed 3–4 times per week is the most effective dietary strategy for iron repletion.
• Non-haem iron foods (legumes, tofu, fortified cereals, pumpkin seeds, spinach) — Plant-based iron sources provide non-haem iron (2–10% absorption). Bioavailability is significantly enhanced by consuming these foods with vitamin C.
• Vitamin C with every iron-rich meal (kiwifruit, capsicum, citrus) — Vitamin C dramatically enhances non-haem iron absorption. Eating a vitamin C-rich food simultaneously with iron-rich plant foods is essential for those relying on plant iron sources, as in vegetarian diets.
• Avoid: tea, coffee, calcium-rich foods within 1 hour of iron intake — Tannins in tea and coffee, and calcium from dairy, significantly inhibit iron absorption. Allow at least 1 hour between iron-rich foods and these beverages or supplements.
• NZ Maori and Pacific diet context — Iron deficiency anaemia has higher rates in Maori and Pacific women and children in NZ. Traditional foods such as kina (sea urchin), paua, and mussels are excellent iron sources. Iron-fortified cereals are an accessible NZ-specific source.

Related Conditions & Medications

Related conditions: Coeliac Disease. Related medications: Iron supplements.