Why iron is so important for the body
Iron is an essential trace element. It is needed above all for the formation of haemoglobin – the red blood pigment that transports oxygen from the lungs to all cells in the body. In addition, iron plays a role in energy production within cells, in the function of enzymes and in numerous metabolic processes.
When iron stores decline slowly, this often goes unnoticed for a long time. The body initially falls back on its reserves. Only when these are largely depleted do typical complaints appear. Iron deficiency is one of the most common nutrient deficiencies worldwide – many people in Austria are also affected, particularly women of childbearing age, pregnant women, growing children, athletes and people following a vegetarian or vegan diet.
Iron deficiency symptoms: how to recognise a deficiency
Symptoms often develop gradually and are non-specific. This means that many signs can also have other causes. If several symptoms occur simultaneously or persist for a longer period, a medical check-up is advisable.
General physical complaints
- Persistent tiredness and rapid exhaustion
- Reduced physical performance, even during everyday activities
- Pale skin and pale mucous membranes
- Headaches, dizziness or ringing in the ears
- Palpitations, shortness of breath on exertion
- Increased susceptibility to infections
Changes to hair, skin and nails
- Increased hair loss or thinning hair
- Brittle, longitudinally grooved or spoon-shaped fingernails
- Dry skin, cracked corners of the mouth (rhagades)
- Burning tongue or a smooth, reddened tongue
Psychological and cognitive symptoms
- Problems with concentration and memory
- Inner restlessness, irritability or low mood
- Sleep disturbances
- Restless legs syndrome (restless legs, especially in the evening)
Not every one of these signs necessarily indicates an iron deficiency. Conversely, a deficiency can also be present without all of the symptoms mentioned occurring. What matters is the overall picture – and a targeted laboratory investigation.
Causes: why does iron deficiency develop?
Iron deficiency can have various causes. Often several factors are involved at the same time:
- Increased requirement: pregnancy, breastfeeding, growth during childhood and adolescence, intensive endurance sports
- Increased losses: heavy or prolonged menstrual bleeding, bleeding in the gastrointestinal tract, frequent blood donations
- Reduced absorption: one-sided diet, vegetarian or vegan diet without careful planning, chronic inflammatory bowel diseases, coeliac disease, status after stomach surgery
- Chronic illnesses: renal insufficiency, heart failure, tumour diseases or underlying inflammatory conditions
Diagnosing iron deficiency: which blood values are meaningful?
Because the symptoms are non-specific, a blood test is the decisive step in reaching clarity. The following laboratory values are usually determined:
Ferritin level – the key storage marker
Ferritin is the storage protein for iron and is considered the most reliable marker of the body's iron reserves. A low ferritin value usually indicates an iron deficiency – even before anaemia develops.
Important: ferritin is also what is known as an acute-phase protein. In cases of inflammation, infections or certain illnesses, it may appear within the normal range or even elevated despite a deficiency. For this reason, the value is always assessed in conjunction with other parameters.
Other important parameters
- Haemoglobin (Hb): indicates whether anaemia is already present.
- Transferrin and transferrin saturation: provide information on iron transport in the blood.
- Serum iron: fluctuates considerably during the day and is of limited significance on its own.
- MCV and MCH: provide information on the size and haemoglobin content of the red blood cells.
- CRP: inflammation marker used to put the ferritin value into context.
The assessment of these values belongs in medical hands, as reference ranges are interpreted differently depending on the laboratory, age, sex and individual situation.
When is a blood test advisable?
A laboratory investigation is recommended when:
- symptoms such as persistent tiredness, hair loss, difficulty concentrating or a drop in performance last longer than a few weeks
- there is an increased requirement (pregnancy, breastfeeding, growth, intensive sport)
- the diet contains little or no animal-based foods
- heavy or prolonged menstrual bleeding is known
- chronic diseases of the gastrointestinal tract are present
- iron deficiency has already been diagnosed in the past
Measuring iron values can also be useful as part of regular preventive check-ups, particularly in at-risk groups.
What to do if iron deficiency is confirmed
Treatment depends on the cause and extent of the deficiency. In principle, the following options are available:
- Dietary changes: iron-rich foods such as meat, pulses, wholegrain products, nuts, oats and green leafy vegetables. Vitamin C (e.g. from fruit) improves the absorption of plant-based iron, while coffee and black tea inhibit it.
- Oral iron preparations: tablets or drops taken by mouth are used for mild to moderate deficiencies. Use should be supervised by a doctor, as dosage and duration are determined individually.
- Iron infusions: in cases of pronounced deficiency, intolerance to oral preparations or certain underlying conditions, intravenous iron administration can be an option.
Self-medication with iron preparations without prior diagnostic work-up is not advisable. Too much iron can harm the body, and underlying illnesses may go undetected.
Conclusion
Iron deficiency is common, can noticeably impair quality of life and is often only recognised late because of its non-specific symptoms. Anyone who feels tired, exhausted or less able to perform for an extended period should take these complaints seriously. A blood test – in particular determining the ferritin value in combination with other parameters – provides clarity and forms the basis for targeted treatment.
This article does not replace medical advice.