If you feel tired frequently, you may have iron-deficiency anemia.

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Do you often feel tired, lethargic, or run down? Is it hard to concentrate? Are you experiencing shortness of breath? You may be suffering from iron-deficiency anemia, a condition that afflicts about one in five women of reproductive age, especially vegetarians or vegans who fail to eat enough iron-rich foods and have heavy menstrual periods.

Premenopausal women need at least 18 milligrams of iron daily, yet many consume 10 milligrams or less. "For most women, that's not a problem unless you're losing excessive iron through your periods, pregnancy, or your intestinal tract because of an ulcer or tumor," says Dr. Craig Kitchens, a professor of medicine at the University of Florida, Gainesville.

Iron helps carry oxygen to the tissues, including the brain. When iron levels dip, the body is short on oxygen, resulting in fatigue, memory loss, poor concentration, apathy, shortened attention span, and reduced work performance.

Other symptoms include: split nails, cold hands and feet, and restless legs. The mineral also plays a vital role in your immune system and metabolizing essential B vitamins. Without adequate iron, you have tired blood that can make you more susceptible to colds and other infections.

Iron-deficiency Anemia

A woman who is iron-deficient has just enough iron to get by, while an anemic woman doesn't have enough iron to meet her body's needs. Causes of anemia include a deficiency of vitamin B or folic acid, an ulcer, hemorrhoids, other internal bleeding.

Once iron stores are depleted, it can take anywhere from a few weeks to 6-12 months for them to be restored depending on the severity of the anemia. If you're treated for iron deficiency and don't feel any better after a month, Kitchens says to tell your doctor but don't stop taking your supplements just because your symptoms improve.

Dr. Sheldon Saul Hendler, co-author of the "PDR Guide to Nutritional Supplements" agrees. "If it takes longer than three months," says Hendler, "there may be more serious underlying causes."

Iron-deficiency anemia can only be diagnosed through a blood test by a qualified health care professional. The serum ferritin, serum iron, and total iron binding capacity measurement tests are used to detect iron deficiency anemia and the results are reviewed along with the hemoglobin, hematocrit, MCB and MCH concentrations.

If all are low, the patient has iron deficiency anemia. If ferritin alone is low, anemia or chronic disease is the probable diagnosis and Kitchens says he would then prescribe the most common form, iron sulfate, to his patients.