But medical professionals are split on the use of iron sulfate. Dr. Robert Rowan, an Anchorage, Alaska-based family practitioner and nutritionist, warns that iron sulfate can be harmful to the stomach and often causes black stools, diarrhea, constipation, bloating, and anorexia.
Rowan points to evidence that supplemental forms of iron can generate free radicals, by-products of oxygen usage that attack and damage brain cells and may advance the loss of memory and thinking. Iron is found in two forms heme and non-heme iron. Heme iron, which makes up 40 percent of the iron in meat, poultry and fish, is well absorbed.
Non-heme iron, 60 percent of the iron in animal tissue and all the iron in plants fruits, vegetables, grains and nuts are less well absorbed. Rowan contents that over-the-counter blood builders made of natural non-heme forms of iron are "much safer, more absorbable, and I see very good results in as little as 30 days but generally a couple of months."
Stephen Sinatra, a Manchester, Conn.-based cardiologist and co-author of the book, "Heart Sense for Women," champions vitamin and mineral supplements but not iron supplements, except in severe cases.
Sinatra says excess iron is linked to heart disease. For iron-deficient patients, Sinatra recommends organic raisins, prune juice, more meats, red wine, and for vegetarians, trail mix, to boost iron levels. "Losing iron is very healing to the heart," says Sinatra.
As for heart disease, a study conducted among 1,900 middle-aged men in Finland, found that a high iron level was second only to smoking as a cause of heart attacks, meaning don't load up on iron unless absolutely necessary.
High levels of iron can be toxic. Experts warn that supplements should not be used to treat anything but iron-deficiency anemia and avoided by anyone with heosiderosis, a precursor to hemochromatosis (some 1 million people in the US or even more may have this hereditary disorder in which the intestines absorb too much iron.
Sufferers are more likely to develop diabetes, cancer, heart disease, and cirrhosis of the liver, as well as certain infections. "There is the lure that iron-tired blood requires iron...but we're learning that iron supplements also have a very dark side," Dr. Hendler warns. "(Iron) can be destructive to the cells and organs, including the liver, heart, and brain."
In fact, too much iron also may be life-threatening warns Dr. Eugene Weinberg, professor emeritus of microbiology at Indiana University at Bloomington. Both cancer cells and infectious organisms need iron from their host to grow, says Weinberg, who has studied the effects of iron for three decades.