That's an alarming fact when you consider that, according to a 1994 Johns Hopkins study, at least 15 percent of all adolescent girls have some form of iron deficiency. But as a group, Americans are in much more danger from overloading on iron than from getting too little. For one thing, although iron deficiency is the most common reason for anemia, it's far from being the only one. Anemias are caused by everything from vitamin deficiencies to defects in the hemoglobin itself or in the bone marrow's production of red blood cells. That distinction isn't always clearly understood.
Iron overload is lethal.
Hematologist Victor Herbert, a professor of medicine at Mount Sinai and Bronx Veteran's Affairs Medical Centers in New York City, and one of the world's foremost experts on nutrition, echoes Crosby's concern. Except for high-risk groups like children and premenopausal women, it's pretty tough for other Americans to come up iron deficient, he says. Not only is iron abundant in unprocessed meat and vegetables, but since the early 1940's the FDA has required that virtually all four products be iron- enriched. In fact, Americans who need extra iron are outnumbered nearly 20 to one by those who don't. Nevertheless, tens of millions of Americans regularly supplement their diets with multivitamins, minerals, or other iron products because they believe it will keep them healthier.