Iron deficiency is a condition in which the body does not have enough iron. Iron is an essential mineral required for the production of red blood cells, which are vital for a healthy immune system, cognitive function, muscle strength, and energy levels.
The primary role of iron is related to hemoglobin, a protein found in red blood cells. Hemoglobin transports oxygen from the lungs to all body cells, allowing them to function properly.
The body cannot produce iron on its own, so it must be obtained through food. If the amount of iron consumed daily is lower than the amount the body uses, iron deficiency develops.
Maintaining adequate iron levels in the body is extremely important. Low iron levels can lead to anemia, while excessive iron levels can be toxic. Iron deficiency is the most common nutritional deficiency worldwide.
Iron deficiency usually develops gradually and is commonly divided into three stages.
Stage 1 – Depletion of iron stores
At this stage, the body’s iron stores begin to decrease. Hemoglobin levels may still be normal, but serum ferritin levels are low. Ferritin is a protein that stores iron. Some people may feel tired or fatigued, although many experience no noticeable symptoms.
Stage 2 – Impaired red blood cell production
At this stage, the body does not have enough iron to produce new red blood cells. Hemoglobin levels may still appear normal, but transferrin saturation (a measure of iron availability) is reduced. Fatigue and dizziness become more common.
Stage 3 – Iron deficiency anemia
This stage is defined as iron deficiency anemia. Hemoglobin levels fall below normal (below 12 g/dL in women and below 14 g/dL in men). Individuals may experience pronounced fatigue, weakness, shortness of breath during physical activity, headaches, dizziness, and heart palpitations.
Iron deficiency can be difficult to recognize, especially in its early stages, as symptoms often develop slowly. Many people may simply feel tired or exhausted.
Common symptoms include:
persistent fatigue and weakness;
shortness of breath;
dizziness and headaches;
poor memory and difficulty concentrating;
reduced physical performance;
decreased academic or work performance;
reduced libido;
rapid heartbeat (tachycardia);
low blood pressure.
Symptoms may appear quickly in cases of severe iron deficiency or sudden blood loss, while moderate deficiency may progress more slowly.
Pregnant women with iron deficiency often experience low energy levels and have an increased risk of preterm birth and delivering babies with low birth weight.
Iron deficiency occurs when the body’s iron stores are insufficient to support normal hemoglobin production. Severe, untreated, or long-term iron deficiency can lead to iron deficiency anemia.
Inadequate dietary iron intake
People who follow restrictive diets, including vegetarians and vegans, are at higher risk. Non-heme iron found in plant-based foods is absorbed less efficiently than heme iron from meat, poultry, and fish.
Increased iron requirements
Higher iron needs occur in infants, children, adolescents, menstruating women, pregnant and breastfeeding women, and physically active women.
Impaired iron absorption
Iron is absorbed in the stomach and intestines. Conditions such as celiac disease or previous stomach or intestinal surgery can reduce iron absorption. Certain dietary compounds, such as phytic acid found in legumes, grains, and rice, can inhibit iron absorption.
Blood loss
Heavy menstrual bleeding, gastrointestinal bleeding, surgery, childbirth, frequent blood donation, inflammatory bowel disease, or parasitic infections can all result in significant iron loss.
You should consult a doctor if you experience:
persistent or severe fatigue and weakness;
shortness of breath;
rapid or irregular heartbeat;
frequent dizziness or faintness;
cold hands and feet;
sore or inflamed tongue;
brittle nails;
poor appetite or increased irritability.
Always seek medical advice before starting iron supplements to ensure the correct type and dosage for your individual needs.
The most reliable way to diagnose iron deficiency is through blood tests. A doctor will usually begin with a medical history review and physical examination.
Common tests include:
Complete Blood Count (CBC);
serum ferritin;
serum iron and transferrin levels.
If gastrointestinal blood loss is suspected, additional tests may be performed, such as stool tests for hidden blood, endoscopy, or colonoscopy.
In rare cases where the cause remains unclear, a bone marrow biopsy may be performed. This procedure is considered the gold standard for diagnosing iron deficiency.
