What is the most abundant iron-containing compound in the body?

Ferritin is recognized as the most abundant iron-containing compound in the body due to its critical role in iron storage. It serves as a reservoir that holds iron in a non-toxic form, facilitating its release when the body requires it for various functions, such as hemoglobin synthesis and cellular metabolism.

In contrast, transferrin primarily functions as an iron transport protein, binding iron in the bloodstream for delivery to cells but does not store it in significant amounts. Myoglobin, found in muscle tissues, binds oxygen and contains iron, but serves a specific purpose in oxygen storage and transport rather than being a primary iron reservoir. Hemopexin is involved in the binding of free heme, which is a byproduct of hemoglobin breakdown, but again, it does not serve as a major storage form of iron like ferritin does.

Thus, ferritin's role as the key stored form of iron in tissues makes it the most abundant iron-containing compound in the body.