While it sounds like a relatively minor condition, it can actually interfere with development of the brain for infants and little children. Researchers have found that severe, chronic iron-deficiency in infancy can lead to motor delays, cognitive delays and behavioral problems later. Sometimes supplementing with iron will work, to bring iron levels back to normal. In addition, eating foods rich in iron such as red meat, liver, raisins, spinach, brocoli and egg yolks could also help increase iron levels in the blood, paving the way for normal development. Other times, supplementation doesn't raise blood levels of iron, When this happens, it becomes necessary to address why the body isn’t absorbing the iron supplements, on top of the essentially symptomatic deficiency.
One possibility is that the damaged gut is unable to absorb nutrients due to gluten intolerance. If you have celiac or gluten intolerance, then only removing gluten will allow the gut to heal so that vitamins can be absorbed.
Another possibility is that bad bacteria has overtaken the gut and the bad bacteria is using the iron as a food source.
In the past we had a lot of beneficial bacteria in our food to keep the bad bacteria in check, but antibiotics as well as food processing has killed the good bacteria as well as the bad bacteria, leaving many people vulnerable to an overgrowth of bad bacteria in their gut.
Getting to the bottom of unexplained anemia should be a priority since it will probably determine your best cause of action to alleviate it and put development back on track (as well as make yourself feel better).
WHAT TO DO: Try to get to the bottom of malabsorption syndromes instead of just treating the symptom. Ask your doctor for an explanation of why you aren't absorbing the iron. If supplementation by itself isn't effective consider eliminating gluten or introducing probiotics, which could help you create more good bacteria to help you get rid of the bad bacteria which is stealing your iron.