Iron deficiency & iron-deficiency anemia: symptoms, causes & therapy

1. What is iron deficiency?

Iron is a vital trace element. The body needs it above all for the formation of hemoglobin — the red blood pigment that transports oxygen. In addition, iron plays a key role in the energy metabolism, in the immune system and in the formation of various enzymes.^¹

Iron deficiency is the most common deficiency disease worldwide. In Europe, according to estimates, a relevant proportion of the population is affected — especially women of childbearing age, children, older people and people with chronic diseases.^¹˒²

2. Stages: from storage iron deficiency to anemia

Iron deficiency generally develops gradually in three stages. The symptoms can already occur in the first stage — long before the hemoglobin falls.^¹

3. Symptoms

Iron-deficiency symptoms can occur already before an anemia and are often misinterpreted as stress, age or overload.^¹˒²

• Fatigue and exhaustion — often the leading symptom, persists even after sufficient sleep
• Concentration problems, forgetfulness, reduced performance
• Pallor — especially of the mucous membranes (eyelids, oral mucosa), palms and nail fold
• Hair loss — diffuse hair loss is one of the most common iron-deficiency symptoms, especially in women
• brittle nails, ridging, spoon nails (koilonychia) in severe cases
• angular cheilitis (cracked corners of the mouth)
• Shortness of breath on exertion, a racing heart
• Restless legs — restless legs, especially in the evening and at night
• sensitivity to cold
• susceptibility to infections — iron is important for the immune system
• Pica — an unusual craving for non-edible substances (e.g. soil, ice, starch); rare, but typical of a severe iron deficiency

4. Causes

Iron deficiency arises when the body loses or uses more iron than is taken in through food. The cause generally has to be clarified — iron deficiency is often a symptom of an underlying disease.^¹

Increased iron loss

• Menstrual bleeding — the most common cause in women of childbearing age; especially with heavy or long bleeding
• Bleeding in the gastrointestinal tract — e.g. with gastritis, stomach ulcers, intestinal polyps, hemorrhoidal bleeding, colorectal cancer, inflammatory bowel diseases (Crohn's disease, ulcerative colitis)
• regular blood donation, blood draws in the chronically ill

Reduced iron absorption

• Celiac disease — a common cause of iron deficiency that is easily overlooked
• inflammatory bowel diseases
• stomach operations, bariatric surgery
• Long-term PPI therapy (pantoprazole, omeprazole) — can impair iron absorption
• an iron-poor diet — especially with a vegan or very one-sided diet

Increased iron requirement

• pregnancy and breastfeeding
• growth phases in children and adolescents
• competitive sport

5. Diagnosis

The diagnosis of an iron deficiency is generally uncomplicated.^¹

• Ferritin: The most important laboratory value for assessing the iron stores. A reduced ferritin proves an iron deficiency. Caution: ferritin is an acute-phase protein — with a simultaneous inflammation, infection or liver disease it can be falsely normal or elevated, even though an iron deficiency is present.
• Blood count: Hemoglobin, MCV (mean cell volume), MCH (mean cell hemoglobin). With iron-deficiency anemia generally: Hb ↓, MCV ↓ (microcytic), MCH ↓ (hypochromic).
• Transferrin saturation: Can help with the assessment, especially when ferritin is distorted by inflammation. With iron deficiency generally reduced.
• CRP: To rule out a simultaneous inflammation that can keep ferritin falsely normal.
• Search for the cause: Gynecological history (menstruation?), gastroenterological work-up (gastroscopy, colonoscopy with suspicion of GI bleeding), celiac serology, medication history (PPI? NSAIDs?).

More: Preparing for a doctor's appointment, Understanding blood values.

6. Therapy: taking iron preparations correctly

The treatment consists of two steps: treat the cause (e.g. stop the source of bleeding, treat celiac disease) and replenish the iron stores. The dosage is determined individually by the treating practice.^¹

7. Intravenous iron administration

When oral iron preparations are not tolerated, do not work sufficiently or a rapid replenishment is necessary, iron can be given intravenously.^¹

The intravenous administration is generally given under medical supervision. Severe allergic reactions are rare, but possible — which is why the infusion is mostly carried out in the practice or outpatient clinic.

8. Nutrition

With a manifest iron deficiency, nutrition alone generally does not suffice to replenish the stores. Nevertheless, an iron-rich diet is sensible in order to prevent a renewed deficiency.

• Heme iron (animal sources) is generally absorbed better than non-heme iron (plant sources): meat, liver, fish
• Plant iron sources: legumes, whole-grain products, oat flakes, spinach (actually less than often claimed), nuts, seeds
• Vitamin C improves the absorption of plant iron — e.g. bell pepper, citrus fruits or broccoli with the iron-rich meal
• Inhibit iron absorption: coffee, tea, milk and calcium preparations — generally keep a gap from iron-rich meals
• With a vegan diet, conscious iron planning is particularly important; regular checking of the iron values is generally recommended

9. Living with iron deficiency

• Iron preparations: take punctually and regularly, even when you already feel better. The stores generally need a few months to fully replenish.
• Checks: ferritin and the blood count are generally checked after a few weeks in order to assess the success of the therapy.
• Interactions: Iron can influence the absorption of other medications (e.g. L-thyroxine, antibiotics, PPIs). Keep a gap. More: Drug interactions.
• Keep an eye on the cause: Iron deficiency often comes back when the cause is not treated. Regular checks are important.

How brite helps you with iron deficiency

Iron in the morning on an empty stomach, then wait half an hour — no coffee, no breakfast with milk, no L-thyroxine in the same second. Iron therapy often fails not because of the preparation, but because of the timing gaps. brite solves that.

• Intake reminder — iron in the morning on an empty stomach, a half-hour gap from breakfast, no coffee at the same time: brite reminds you punctually and can also include the vitamin C note. Set up a reminder
• Interaction check — iron plus L-thyroxine? Plus a PPI? Plus antibiotics? brite shows which medications block iron absorption — and which gaps make sense. Check now
• Health history — document ferritin, hemoglobin, energy and symptoms over time. This makes it easy to see whether the therapy is working — and whether the deficiency comes back after stopping. Track your history
• Digital medication plan — all medications clearly organized for the GP, gynecology and gastroenterology. Important, because the search for the cause often involves several specialists. Go to medication plan

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