High-iron diet raises gallstone risk

Men who consume large amounts of 'haeme' iron in their diets have an increased risk of developing gallstone disease. Haeme iron, one of two types of iron found in foods, is bound to either the blood protein haemoglobin or the muscle protein myoglobin. While haeme iron, which comes from consumption of meat, poultry, and fish, contributes a smaller portion of iron to typical western diets than non-haeme iron, it is more readily absorbed from the gastrointestinal tract. Researchers from the University of Kentucky Medical Center, Lexington, USA, evaluated dietary levels of haeme and non-haeme iron and the risk of gallstones in 44,758 men participating in the study from 1986 to 2002. A total of 2,468 cases of gallstones were documented during the follow-up period. Of these, 1,453 men required removal of the gallbladder. High levels of haeme iron in the diet raised the risk of developing gallstones by 21 percent, whereas high levels of non-haeme iron seemed to have no effect. In general, continuous ingestion of large amounts of iron may cause substantial harm because the body has no way of excreting excess iron in cases of dietary overload.