Iron is one of the most important minerals for healthy human functioning. Aside from being a necessary ingredient of many proteins and enzymes, iron is crucial for the transportation of oxygen throughout the body via red blood cells. This mineral is also crucial for cell growth and regulation. Dietary iron is found in many foods, such as meats (especially red meat), leafy green vegetables and some grains, like iron-fortified cereals. The recommended daily allowance of iron depends on age, gender, health and pregnancy.
Iron deficiency is a common problem -- some scientists estimate that 80 percent of the world is iron-deficient, with 30 percent suffering from full-blown anemia. When iron intake is too low, the body slowly uses up its stored supplies, causing no overt symptoms at first. Eventually, anemia develops, in which blood hemoglobin levels become too low. The symptoms of anemia include fatigue, lowered concentration and performance at school and work, developmental problems, weakened immune system and inflamed tongue (glossitis).
While many deficiencies are caused by a poor or incomplete diet, some iron deficiencies are due to other health issues, such as poor iron-absorption, vitamin A deficiency or prolonged bleeding, such as during menstruation. Iron deficiencies can be corrected by instituting a proper, balanced diet along with the use of iron supplements. These supplements may cause negative side effects, including digestive and gastrointestinal issues. Iron supplements should be taken carefully, as too much iron is perhaps worse than not enough.
As with any nutrient, you can get too much of a good thing. The body cannot easily excrete iron, causing a buildup of the mineral in the body's organs and tissues if too much is ingested. Over time, this can lead to numerous medical problems, and even death. This is why it is so important to take iron supplements under the supervision of a doctor. In addition, acute ingestion of high levels of iron can lead to death -- a child can die if he or she ingests 200 milligrams (just over seven thousandths of an ounce) of iron. For this reason, iron supplements should be kept out of the hands of children.