Wednesday, May 02, 2012
Iron is a vital element to our health, and humans have developed elaborate ways of handling iron, mostly absorbing and storing it. In fact, there is no mechanism for eliminating iron from the body, and therefore it can accumulate to excessive levels in some conditions, including iron poisoning.
Too high an iron level or poisoning can produce rapid deterioration of the kidneys, liver, and heart function. Poisoning is usually seen in children who have accidentally eaten their mother’s iron pills. It is very important that iron pills, in fact all medicines, be kept safely out of the hands of children.
A slow accumulation of excessive iron in the body is much more commonly seen in adults, and it can have a number of causes. Hemochromatosis is perhaps the most common condition in which this is seen.
Hemochromatosis is either genetic, or acquired, meaning that it is a result of another condition such as anemia. The genetic form of hemochromatosis is quite common, with about 10 percent of people of European origin carrying one of the genes, and about 0.3 percent of this population carrying both of the genes for this disease, meaning that they received one gene from each parent. It takes many years for someone even carrying two genes for this disease to build up enough iron in the body to be harmful, and women are protected from this condition by their monthly loss of iron until they stop menstruating. Nonetheless, people carrying two genes for the disease will often have high iron levels in the blood even before they have developed any of the signs of hemochromatosis, and this may serve as a warning to start treating the iron buildup by withdrawing blood on a regular basis. Such people with early cases of hemochromatosis should certainly not take iron supplements.
Some anemias — the most common is probably thalessemia major — will lead to an excessive buildup of iron because the anemia itself causes the body to absorb iron from food more efficiently, and people with these anemias often must be given transfusions that add iron to the body. Since the body has no way to dispose of this added iron, it will start to build up and eventually lead to symptoms of hemochromatosis.
Chronic alcoholics with liver disease will often have elevated levels of iron in the blood, probably because of iron released from liver cells that are damaged by the alcohol. Of course, many alcoholics may also carry the genes for hemochromatosis, and in these cases the increased iron in the body can produce the liver, kidney, and heart complications of that disease. Iron buildup in alcoholics who do not carry hemochromatosis genes will usually not lead to organ damage. (Enough of that is already caused by the alcohol.)
When doctors do tests to evaluate the amount of iron a person has, they will often do a ferritin test as well as or instead of measuring the iron directly. Ferritin is a protein that stores iron in the liver and elsewhere, and some can be measured in the blood. It will be high in hemochromatosis, alcoholic liver disease, anemias such as thalessemia major, and in any type of acute liver inflammation or hepatitis. Ferritin will be low, as will the iron in the blood, in the most common kind of anemia, iron deficiency anemia.
With rare exceptions, people who do not carry hemochromatosis genes, and don’t have thalessemia or alcoholic liver disease cannot damage themselves by taking small or medicinal doses of iron even for many years. However, since most of us don’t know if we are carrying hemochromatosis genes, taking iron routinely is not advised unless one is known to have iron deficiency anemia.