Overdoing iron
Recent studies have found no link between excess iron and heart desease
by Dave Schiller

The essentials for ensuring adequate iron intake appeared in the January-February 1997 issue of Lifelines in an article by Sejal Parikh-Shah, N.D., B.Sc.. The point is well-made that vegetarians do not have to struggle for sufficient iron.
Only some dietary iron is absorbed by the body. Low intake doesn't necessarily result in deficiency. Many factors govern iron absorption, including its dietary source, and what other foods are consumed at the same time. For example, vitamin C greatly boosts absorption.
Iron under some circumstances can be too much of a good thing. Some physicians have become outspoken with their concern that people taking supplements may get excessive iron. One is Ralph Golan, M.D., author of Optimal Wellness. He calls the presence of up to 18 milligrams of iron in some multivitamin/mineral supplements "a mistake."
"Generally speaking, iron should be taken only by those adults who have documented low iron stores, or a susceptibility to such, and by pregnant, lactating or menstruating women," Dr. Golan writes. "If you do not fit these categories, you should probably not take any supplemental iron, either in a multiple or separately."
Golan warns that excess iron can injure arterial walls and aggravate tumor growth. Symptoms of progressed iron toxicity include fatigue, headache, joint and abdominal pain, bronze skin color, weight loss, and the signs of diabetes: excessive urination, thirst and hunger.
For people with a common hereditary disorder known as hemochromatosis - iron overload disease - the results can be serious, including damage to the liver and pancreas. About one in 400 people of northern European descent have the condition, which is mitigated by periodically donating blood, thereby lowering the amount of stored iron.
Doubt has been cast on the connection between high iron stores and heart attacks, a theory proposed in 1981 and reinforced by a Finnish study in 1992. According to a review of the literature in the July 1996 issue of the UC Berkeley Wellness Letter, more recent studies in Iceland and at Harvard found no relation between the level of ferritin, the iron-containing protein complex that is the body's main storage medium, and coronary artery disease (CAD).
Three other studies of transferrin, the protein used by the body to transport iron, revealed no link with heart disease; one of these found a positive benefit to higher levels. Out of five case-control studies comparing CAD patients with healthy controls, only one had the statistics to link iron levels with heart disease. Two more studies involving autopsies found no connection between high iron stores and CAD.
Scientific studies supporting the notion that iron overload increases cancer risk have yet to appear. The daily iron requirement varies with age, gender and who you ask. In the U.S. the established RDA (Recommended Daily Allowance) is 18 milligrams. The Department of Public Health Services in Hamilton, Ontario, advised the following figures last year: children, 6 to 8 milligrams; adolescents, 10 to 13 milligrams; adults, 8 to 13 milligrams. Up to 23 milligrams are recommended for women in the second and third trimester of pregnancy, due to the demands of the growing fetus establishing its own blood supply. Others at risk of developing iron deficiency include dieters, premenopausal women and long distance runners who may suffer a form of anemia called footstrike hemolysis, in which red blood cells passing through the feet are crushed on impact.
What's the best advice about iron? Rely on a healthy, balanced diet and don't take iron as a supplement unless you are in a deficiency risk group. If you have symptoms of deficiency or toxicity, see a physician.

References:
Athletes benefit from slight anemia, Allan Bruckheim, The (Montreal) Gazette (Oct. 23, 1996, Food section).
Gene Found for Iron Buildup, The New York Times, (July 31, 1996, p. 7).
Optimal Wellness, Ralph Golan, M.D., Ballantine (1995).
Special report: iron overkill, UC Berkeley Wellness Letter (July 1996, pp. 4-5).
Taking a hard look at the body's iron needs, Lynn Garrison, The (Hamilton, ON) Spectator (Jan. 17, 1996, Food section).