Which test is used to assess iron stores in the body?

Ferritin is the correct answer because it is a protein that stores iron in the body and releases it in a controlled fashion when needed. Measuring the level of ferritin in the blood provides a reliable indication of the amount of stored iron, helping to assess iron deficiency or overload conditions. A low ferritin level typically reflects depleted iron stores, making it essential in diagnosing conditions such as iron deficiency anemia.

Folate is primarily associated with the evaluation of vitamin B9 levels in the body, which is important for cell division and the formation of DNA, but it does not provide information regarding iron stores. BUN, or blood urea nitrogen, is a measure of kidney function rather than iron levels, while GGT (gamma-glutamyl transferase) is an enzyme that is often evaluated to assess liver function and is not relevant to iron status. Therefore, ferritin is the specific marker for assessing iron stores.