Serum ferritin is a protein that stores and releases iron in the body. It is found in the blood and reflects the amount of iron stored in tissues. Measuring serum ferritin levels helps assess a person's iron status, indicating whether they have enough iron or are at risk of deficiency. Low serum ferritin levels can suggest iron deficiency anemia, a condition where the body lacks sufficient iron to produce healthy red blood cells. Conversely, high levels may indicate excess iron or conditions like hemochromatosis, where the body absorbs too much iron from food.