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Iron Deficiency

By

Larry E. Johnson

, MD, PhD, University of Arkansas for Medical Sciences

Reviewed/Revised Jul 2023
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Iron (Fe) is a component of hemoglobin, myoglobin, and many enzymes in the body. Heme iron is contained mainly in animal products. It is absorbed much better than nonheme iron (eg, in plants and grains). Nonheme iron accounts for > 85% of iron in the average diet. However, absorption of nonheme iron is increased when it is consumed with animal protein and vitamin C.

Iron deficiency is one of the most common mineral deficiencies in the world. It may result from the following:

Chronic bleeding due to colon cancer is a serious cause in middle-aged and older people.

Diagnosis of iron deficiency involves complete blood count, serum ferritin and iron levels, and possibly measurement of transferrin saturation (iron-binding capacity). In deficiency states, iron and ferritin levels tend to be low, and iron-binding capacity tends to be high (3 General references Iron (Fe) is a component of hemoglobin, myoglobin, and many enzymes in the body. Heme iron is contained mainly in animal products. It is absorbed much better than nonheme iron (eg, in plants... read more ).

Rarely, when the diagnosis of iron deficiency remains uncertain, examination of bone marrow for iron may be necessary.

Treatment of iron deficiency involves correcting the cause if possible (eg, treatment of a bleeding intestinal tumor). All people with moderate or severe iron deficiency and some people with mild deficiency require iron supplementation Treatment Iron deficiency is the most common cause of anemia and usually results from blood loss; malabsorption, such as occurs in celiac disease, is a much less common cause. Symptoms are usually nonspecific... read more Treatment .

General references

  • 1. Coates A, Mountjoy M, Burr J: Incidence of iron deficiency and iron deficient anemia in elite runners and triathletes. Clin J Sport Med 27:493–4986, 2017. doi: 10.1097/JSM.0000000000000390

    2.Kalra PR, Cleland JGF, Petrie MC, et al: Intravenous ferric derisomaltose in patients with heart failure and iron deficiency in the UK (IRONMAN): An investigator-initiated, prospective, randomised, open-label, blinded-endpoint trial. Lancet 400 (10369): 2199–2209, 2022. doi: 10.1016/S0140-6736(22)02083-9 Epub 2022 Nov 5.

    3. Snook J, Bhala N, Beales ILP, et al: British Society of Gastroenterology guidelines for the management of iron deficiency anaemia in adults. Gut 70 (11):2030–2051, 2021. doi: 10.1136/gutjnl-2021-325210 Epub 2021 Sep 8.

Drugs Mentioned In This Article

Drug Name Select Trade
MONOFERRIC
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NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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