Iron is an essential mineral necessary for the production of various enzymes and proteins, such as hemoglobin -- the protein in red blood cells that carries oxygen throughout the body. The National Institutes of Health Food and Nutrition Board specify the daily recommended intake of iron as 8 mg for men and post-menopausal women and 18 mg for women 19 to 50 years of age. Those at risk for developing iron-deficiency anemia may benefit from taking iron supplements. Iron supplements can cause side effects, the most common being constipation.
Iron Deficiency
Although many of us consume adequate amounts of iron through a well-balanced diet, the National Institutes of Health Office of Dietary Supplements reports that 80 percent of the world's population may be iron deficient. Iron-deficiency can lead to anemia, a medical condition characterized by a decrease in functioning red blood cells. Anemia causes symptoms such as fatigue, dizziness, chest pain, shortness of breath and cold hands and feet. Although taking iron supplements may initially cause constipation, treating the anemia can help prevent further complications such as heart problems and delayed growth.
Risk Factors
Several factors can increase your risk of becoming iron deficient. Pregnancy causes a woman's blood volume to increase between 40 to 50 percent, according to the Cleveland Clinic. To accommodate the additional blood, pregnant women should consume 27 mg of iron per day. If you suffer from a digestive disease, such as Crohn's disease or celiac disease, the intestines may fail to absorb iron efficiently leading to a deficiency. Others at risk include those with kidney disease, low birth weight infants and women with heavy menstrual cycles.
Types of Iron
Iron supplements may contain ferric iron or ferrous iron -- two different forms of iron that differ in the number of negatively charged electrons they carry. Doctors most commonly suggest taking ferrous iron supplements because the body more readily absorbs the iron. Ferrous iron supplements combine the iron with salts creating ferrous sulfate, ferrous gluconate and ferrous fumarate. Ferrous gluconate contains the least amount of available iron, only 12 percent as listed by the National Institutes of Health Office of Dietary Supplements, but also causes fewer cases of constipation.
Side Effects
Taking iron supplements causes stools to appear dark green or black. This side effect occurs due to the unabsorbed iron and should not cause concern. Common gastrointestinal side effects include constipation or diarrhea, nausea, vomiting and abdominal cramps. These side effects may be minimized by taking an enteric coated or delayed release form of the supplement.
Prevention
To avoid developing constipation, ask your health care professional about starting your iron supplements at a low dosage. Starting at a low dosage and gradually increasing over the first few weeks can help the intestines adjust to the changes and decrease the occurrence and severity of constipation. Many doctors suggest taking your iron supplements on an empty stomach, either one hour before or two hours after eating a meal to avoid interactions with certain foods. If stomach upset and constipation occur, try taking the iron supplement with food, as suggested by the National Anemia Action Council.
