Unbalanced diet, specially in children and elderly, is most responsible for iron deficiency. Elderly patients often have poor appetite which leads to iron deficiency. Chronic diarrhea and dysentery, malabsorption, biliary disorders, surgery, increased motility of intestine and interfering substance in food or drugs decrease iron absorption. Most frequent cause in females is menstrual loss. The average iron requirement in menstruating female is 1,5 to 2 mg of elemental iron per day in comparison to 1 mg daily in an adult male.
Intestinal parasites are very important cause of blood loss.
Hookworm anaemia is a very well recognized condition. Worms not only suck blood but they also compete for dietary proteins, minerals and also damage the intestinal mucosa or cause diarrhea. Chronic blood loss from peptic ulcer, piles or cancer are other cause of anaemia. Usually there is also a deficiency of other dietary constituents like Vitamin. B12, Folic acid etc.