Iron supplements are over-the-counter dietary supplements that are commonly prescribed to patients who display symptoms of iron-deficiency diseases such as anaemia, where the deficiency cannot be quickly and easily corrected with normal diet alone. A doctor will obtain a blood test for analysis of serum ferritin levels when an iron deficiency is suspected. Serum ferritin is a form of iron which is stored in the blood. Low levels indicate a deficiency. Iron supplements can be prescribed to prevent iron deficiencies in other circumstances, such as in pregnancy, renal failure and diseases that prevent the normal absorption of nutrients in food. However, the potential for toxicity and overdose is high and carries several risks and dangers to your health.
A high dosage of iron supplements--more than 45 mg per day for long periods of time in an adult--can increase a person's chances of acquiring iron-overload toxicity and trigger hemochromatosis. Hemochromatosis is a genetic disorder wherein the an individual's body absorbs and stores iron more readily than is normal. This causes excess iron to be stored in multiple organ systems, and can lead to heart and liver failure, as well as severe pancreatic damage. Hemochromatosis usually remains undetected until damage to an organ occurs. To a person with hemochromatosis, what would be a normal dosage of iron to others would be extremely toxic to them. A physician should monitor patients taking iron supplements for long periods of time for any sign of overload.
Iron supplements often cause gastrointestinal upset even if the dosage isn't toxic. A common but harmless side effect is dark stool. Patients taking iron supplements are at risk for vomiting, diarrhoea, intestinal damage and discomfort, indigestion and constipation. In rare cases, these symptoms can become severe enough to require hospitalisation or even cause death. Most patients experience these side effects in their mild-to-moderate form. Patients can lessen and even eliminate their chances of side effects by starting with a very low dosage and gradually increasing to the desired dosage level.
Though the studies haven't been entirely conclusive, several researchers have linked the long-term ingestion of iron supplements to a higher incidence of coronary disease. Clinicians are still unsure about the causal relationship between the two, but one theory is that iron increases the presence of free radicals--a type of blood molecule that speeds up cell oxidation and causes cell damage--in the circulatory system. Long-term use of iron supplements, particularly in very high doses, has also been linked to higher incidences of breast and ovarian cancer.