The term availability means the percent of dietary iron that is absorbed via the gastrointestinal tract to the bloodstream. Non-absorbed iron is lost in the feces. Interactions between various foods can influence the absorption of dietary iron. Vitamin C can increase the absorption of dietary iron. Thus, if a plant food, such as rice, is consumed with orange juice, then the orange juice can enhance the absorption of the iron of the rice.
Phytic acid is a chemical that naturally occurs in legumes, cereals, and nuts.
Nearly all of the iron in plants is nonheme-iron. Much of the iron in meat is nonheme-iron as well. When an abnormally high presence of blood is found in the feces during a fecal occult blood test, the physician needs to examine the gastrointestinal tract to determine the cause of bleeding. Here, the diagnosis for iron deficiency anemia includes the examination using a sigmoidoscope. The sigmoidoscope is an instrument that consists of a flexible tube that permits examination of the colon to a distance of 60 cm.