Each worm can provoke the loss of up to 0.25 ml of blood per day. Several genetic diseases exist which lead to bleeding diorders, and these include hemophilia A, hemophilia B, and von Willebrand's disease. Of these, only von Willebrand's disease leads to gastrointestinal bleeding. The symptoms of iron deficiency anemia include weakness and fatigue. These symptoms result because of the lack of function of the red blood cells, and the reduced ability of the red blood cells to carry iron to exercising muscles.
Iron deficiency can also affect other tissues, including the tongue and fingernails.
Prolonged iron deficiency can result in changes of the tongue, and it may become smooth, shiny, and reddened. This condition is called glossitis. The fingernails may grow abnormally, and acquire a spoon-shaped appearance. Decreased iron intake is a contributing factor in iron deficiency and iron deficiency anemia. One can see that apples, tomatoes, and vegetable oil are relatively low in iron, while whole wheat bread and beef are relatively high in iron.