September 9, 2011
Dear Mayo Clinic:
I've followed the no-iron-supplement guidelines for postmenopausal women for years even though I have a lifelong history of mild anemia. I just purchased my daily vitamin supplement and saw that at least two well-known brands have added a small amount of iron to their senior formula. Why the change? Is this safe to take?
You are wise to be cautious about taking extra iron. Typically, iron supplementation is not recommended for postmenopausal women, because as women age, their need for iron goes down. Some recent research has shown that postmenopausal women may be at risk for anemia. But, even with those findings in mind, taking additional iron may not be a good option for you. Before you take a vitamin supplement that contains iron, talk to your doctor.
Iron is a mineral that helps the body make red blood cells. Without enough iron, the body can't produce the number of red blood cells it needs. This condition, called iron deficiency anemia, is a concern because red blood cells carry oxygen to the body's tissues. Without enough red blood cells, body tissues may not be able to get enough oxygen to stay healthy.
Too much iron (iron overload) can be a problem, too. When the body has more iron than it needs, that iron is stored in places it doesn't belong, such as internal organs. Extra iron can be toxic to those organs, particularly the liver, heart and pancreas, and can damage the joints, as well.
Because both too much and too little iron have the potential to cause health problems, getting the right amount of iron is critical for good health. For women, that amount changes over time. Before menopause, women usually need about 18 milligrams (mg) of iron each day. After a woman stops menstruating, that requirement goes down considerably to about 8 mg of iron a day.
Recently, findings from a large national research study, called the Women's Health Initiative, showed that postmenopausal women may be at increased risk for anemia. Although there are many causes of anemia, iron deficiency is often the culprit and a diet poor in iron is frequently the underlying cause. It may seem obvious that if iron deficiency is a concern, taking more iron in the form of a supplement is a reasonable solution. That's likely the reason some companies have begun adding iron into vitamin supplements geared toward seniors. But it's not that simple.
No research findings show that using an iron supplement will decrease the risk of anemia in postmenopausal women. Instead, a well-balanced diet that includes iron-rich foods — such as beef and other meats, beans, lentils, iron-fortified cereals, dark green leafy vegetables and dried fruit — is the best way to get the iron your body needs. That's because your body absorbs and processes iron from food more effectively than the iron found in supplements.
In addition, even with the increased risk of anemia, postmenopausal women still may experience iron overload if they take in too much iron. The signs and symptoms of iron overload usually develop slowly and subtly, making them difficult to recognize. They include nonspecific symptoms such as joint pain, fatigue and abdominal pain.
See your doctor before you take a vitamin supplement that contains iron. The doctor may recommend that you have your iron level tested to find out if it's normal. With results from that test, you and your doctor can make an informed choice regarding the amount of iron you need and the healthiest way to get it.
— Jacqueline Thielen, M.D., Women's Health Clinic, Mayo Clinic, Rochester, Minn.