What is the best specimen for testing the levels of iron in the blood?

In assessing iron levels in the blood, the correct choice is the specimen collected in a tube that contains EDTA. EDTA, or ethylenediaminetetraacetic acid, acts as an anticoagulant, preventing the blood from clotting. This is essential for accurate laboratory testing as clotting can alter the concentration of various substances, including iron, in the serum.

When evaluating iron levels, it's critical to ensure that the sample is not contaminated or affected by variables that could skew results. Using a tube containing EDTA helps maintain the integrity of the blood sample, allowing for more reliable measurements of iron and its associated parameters, such as ferritin and transferrin saturation.

Collecting blood in a red-top tube, which does not contain anticoagulants and is used for serum tests, can still be valid for certain tests but may not be ideal for specific iron assessments due to potential clotting.

Fasting before a blood draw is often recommended for many tests to avoid fluctuations in certain analytes; however, it is not exclusively necessary for iron studies.

Lastly, the lavender tube is typically used for hematology tests and contains EDTA, but does not specifically indicate whether it’s the best option for iron levels compared to dedicated