Iron is classified as a trace element in the body. After being absorbed, the iron in food is transported by transferrin to places of consumption, such as bone marrow and liver, to be consumed. Iron often plays a role in their biological activity as part of the structure of various proteins. Iron is present in hemoglobin, myoglobin, cytochromes, and a number of enzymes such as peroxidase. High levels of serum iron are seen in hemochromatosis, hemolytic anemia, iron poisoning and hepatitis. Malnutrition, chronic bleeding, iron deficiency anemia and insufficient absorption of iron from the intestine cause a decrease in the level of iron in the body. However, interpretation