Iron is an essential nutrient for haemoglobin and oxygen transport, but fatigue does not equate to iron deficiency, and deficiency does not always progress to anaemia. Long-term self-supplementation can mask underlying issues like bleeding or malabsorption, and may lead to gastrointestinal discomfort or toxicity.
Assess Status, Then Identify the Cause
Blood counts, haemoglobin, and ferritin are useful indicators, but results must be interpreted in the context of inflammation, menstruation, diet, pregnancy, recent blood loss, and gastrointestinal health. Relying on a single number or test result may be insufficient.
If iron deficiency is confirmed, the cause must be addressed: heavy menstruation, inadequate dietary intake, blood donation, increased pregnancy demands, malabsorption, or gastrointestinal bleeding. Supplementation restores reserves but does not replace the need to identify the source of ongoing loss.
Ferritin Is Not an Isolated Metric
Ferritin reflects iron stores but can also rise during inflammation, infection, or liver issues. A 'normal' result does not always rule out deficiency, and low results must be viewed alongside haemoglobin, red blood cell indices, transferrin saturation, and symptoms. Laboratory reference ranges do not equate to personal treatment targets.
For men, post-menopausal women, or those without clear menstrual or dietary causes, ruling out chronic blood loss or malabsorption is critical. Repeatedly correcting levels without investigating the cause can delay essential treatment.
Consider Dietary Sources and Absorption
Haem iron from meat and seafood is typically well-absorbed; legumes, dark green vegetables, and fortified foods provide non-haem iron. Pairing with vitamin C-rich foods can enhance non-haem absorption, while tea, coffee, and certain calcium-rich foods or supplements may inhibit it.
This doesn't require an overly complex diet. Focus on long-term patterns, such as consuming strong tea with every meal or following a plant-based diet without a stable iron source.
Individualise Dose and Tolerance
Common side effects include nausea, abdominal pain, constipation, or dark stools. Iron salts vary in elemental iron content and cannot be compared by total compound weight. Daily or alternate-day regimens, doses, and duration should be based on medical status and professional advice.
Do not increase the dose simply because you don't feel an immediate improvement. Haemoglobin recovery and iron store repletion take time; follow-up testing is more reliable than subjective feelings.
Vitamin C can enhance non-haem iron absorption, but it is not always necessary to supplement high doses with every iron tablet. Taking iron on an empty stomach may improve absorption but can increase gastrointestinal discomfort. Balance absorption and compliance by discussing meal-timing and spacing with coffee, tea, calcium, or other medications.
Dark stools are common with oral iron, but tarry, viscous stools accompanied by dizziness, pain, or vomiting blood should not be attributed to supplements and require immediate medical attention.
Child Safety and Medication Spacing
Iron overdose is dangerous for children; supplements must be stored securely out of reach. Iron can affect the absorption of thyroid medication, certain antibiotics, and other drugs; consult a pharmacist regarding proper spacing.
Iron supplementation is a matter of precision nutrition: identify the deficit, find the cause, choose a tolerable dose, and use follow-up tests to determine when to continue or stop.
