Iron: Are You Getting Enough?
Lethargy. Fatigue. Listlessness. Busy people attribute it to stress. Others are convinced that they need more sleep. But one possible cause is iron-deficiency anemia.
"I'm always tired, but I've gotten used to it," says Kathy, 49, an administrative assistant at a busy health clinic. "I come home from work, cook dinner, usually clean or do laundry. And I'm wiped out. Maybe I should get to sleep earlier, but it never seems to work out that way."
"I thought I was just run down and stressed out," says Julie, 28, a graduate student who admits that she often burns the midnight oil. "I just attributed everything to 'stress.' I had no idea there was a medical cause."
Kathy and Julie both have iron-deficiency anemia. It is a condition that develops because the body's stores of iron are slowly depleted. Women of childbearing age are at risk for this condition because of the blood loss during menstruation. In addition, some women do not get enough iron in their diets to make up for these losses.
Symptoms of iron-deficiency anemia may include:
Should You Be Concerned About Iron-deficiency Anemia?
Menstruating women lose a significant amount of blood every month. Iron escapes right along with it. Unless iron is replaced, these monthly losses can drain stores over time. While premenopausal women need more iron than men, they generally eat less. This complicates the challenge of getting enough iron from foods.
Iron deficiency is also common among:
Why Is Iron So Important?
Iron is the central component of heme. Heme is a molecule used to build hemoglobin, the oxygen-carrying part of red blood cells. Oxygen is used by your body to help make energy. When iron stores are low, the body cannot make enough hemoglobin. There is then less oxygen to help generate energy. Iron also allows the normal functioning of the immune system, the production of collagen (wound healing), and the formation of amino acids, which are the backbone of proteins.
As levels of hemoglobin in the blood decrease, the symptoms of anemia start to appear:
Anemia comes on slowly, so many people do not realize that they have it. Is it possible to have symptoms of iron deficiency without being anemic? Slight iron deficiency, too mild to cause anemia, may still cause symptoms, such as fatigue and decreased exercise capacity.
How Much Iron Do You Need?
The following table shows the Office of Dietary Supplements' Recommended Dietary Allowance (RDA) for iron:
Do not take iron just because you feel tired. Make sure to get tested to see whether you are indeed deficient. With iron, more is definitely not better. Excessive iron intake can be harmful.
Iron and Your Diet
If you have been diagnosed with iron-deficiency, your doctor has probably advised you to include more iron in your diet. If anemia is severe, an iron supplement, such as ferrous sulfate, may be prescribed. Knowing which foods are rich in iron is the first step toward boosting your iron stores. Take a look at the list below to put more iron on your menu.
When adding iron to your diet, keep in mind that there are different forms of this mineral:
Nutritionists have traditionally grouped meat, fish, and poultry together as the best sources of heme iron. But scientists at Utah State University published some results showing that some types of meat may pump more iron into your system than others. The winners? Beef ranked first for heme iron content, followed by lamb, pork, turkey, and chicken. Eggs are also a good source of heme iron.
Eating for Energy
It is not enough to know where iron is lurking. You also have to get it into your system. This is somewhat more difficult for vegetarians since all nonmeat forms of iron are nonheme, and therefore less well absorbed. But, it is certainly not impossible. Here are some tips:
Good Dietary Sources of Iron
The Vegetarian Society
Annibale B, Capurso G, Chistolini A, et al. Gastrointestinal causes of refractory iron deficiency anemia in patients without gastrointestinal symptoms. Am J Med. 2001;111:439-445.
DynaMed Editorial Team. Iron deficiency anemia in adults . EBSCO DynaMed website. Available at: http://www.ebscohost.com/dynamed/. Updated January 31, 2011. Accessed April 7, 2011.
DynaMed Editorial Team. Iron deficiency in children (infancy through adolescence). EBSCO DynaMed website. Available at: http://www.ebscohost.com/dynamed/. Updated December 7, 2010. Accessed April 7, 2011.
Health Library editorial staff and contributors. Iron-deficiency anemia. EBSCO Health Library website. Available at: http://www.ebscohost.com/healthLibrary/. Updated September 2010. Accessed April 6, 2011.
Iron. Center for Young Women's Health website. Available at: http://www.youngwomenshealth.org/iron.html. Updated January 26, 2009. Accessed April 7, 2011.
Iron. National Institutes of Health, Office of Dietary Supplements website. Available at: http://ods.od.nih.gov/factsheets/iron/. Accessed April 7, 2011.
Killip S, Bennett JM, Chambers MD. Iron deficiency anemia [review]. Am Fam Physician. 2007;75:671-678.
Patrick LR. Restless legs syndrome: pathophysiology and the role of iron and folate [review]. Altern Med Rev. 2007;12:101-112.
Verdon F, Burnand B, Fallab-Stubi CL, et al. Iron supplementation for unexplained fatigue in non-anaemic women: double blind randomised placebo controlled trial. Br Med J. 2003;326:1124.
Last reviewed April 2011 by Brian Randall, MD