What blood values we recommend to have measured when iron deficiency is suspected in the bodyUpdated 4 months ago

In case of suspected iron (Fe) deficiency in the body, we recommend having multiple blood markers tested, as serum iron alone is not sufficient to reliably confirm anemia. We suggest discussing blood test results with your healthcare provider.

Below are the key laboratory values that should be included in the evaluation:

Basic blood count (CBC):

• Hemoglobin (Hb) – decreased in anemia

• Hematocrit (Hct) – the proportion of red blood cells to total blood volume

• Red blood cells (RBC) – the number of red blood cells

• MCV, MCH, MCHC – indicate the size and hemoglobin content of red blood cells; typically decreased in iron deficiency

Specific markers of iron metabolism:

• Ferritin – the storage form of iron in the body. It is the most reliable indicator of iron deficiency — low ferritin levels reflect depleted iron stores. 
  However, it may be falsely elevated in cases of infection or chronic inflammation, as ferritin is also an acute-phase marker.

• Serum iron – reflects the current level of iron in the blood. It fluctuates (even based on recent diet and red meat intake) and is not sufficient alone for diagnosis.

• Transferrin – a protein that transports iron in the blood.
  Its levels rise significantly in iron deficiency as the body attempts to increase iron uptake from food.

• Transferrin saturation (TSAT) – shows the percentage of transferrin that is bound to iron.
  Low values indicate functional iron deficiency.

• CRP – important for evaluating inflammation in the body, which may distort ferritin values.

Common symptoms of anemia, such as fatigue, shortness of breath, paleness, reduced physical performance, and weakened immunity, may also be caused by deficiencies in vitamin B9 (folic acid) and B12.
Therefore, it's advisable to also perform a differential diagnosis, including measurement of these two vitamins, which are essential for blood formation.