Two sides of Iron: Anemia & Hemochromatosis

Do I need Iron? Or do I have Hemochromatosis (Iron overload)?

By Dr. Emily Brown Reeves, PhD, CNS

Iron is a critical nutrient required for proper cellular function. Blood formation, oxygen transport, energy production, detoxification and DNA synthesis all depend upon the iron atom.  

Daily requirements for iron depend on an individual’s gender, genetic makeup, age and lifestyle. The recommended daily allowance (RDA) of iron was set by the Institute of Medicine in 2001 at 8 mg/day. Special attention in this discussion will be given to genetic variation that may alter the RDA for iron.

Important early symptoms of iron deficiency are the inability to sustain physical work and impaired cognitive function. Those at high risk for iron deficiency are women, infants and children, and vegetarians.  Iron deficiency symptoms may present as delays in psychomotor development, pale skin, heart murmurs, low appetite, and cravings for dirt or ice.  

In contrast to iron deficiency, iron overload is the accumulation of excess iron in the body.  Iron overloading is a dangerous condition that can cause progression of  neurodegenerative diseases such Alzheimer’s, Parkinson’s and Huntington’s Disease.  Symptoms of iron overload include chronic fatigue, bronze or gray skin, joint pain, liver disease, hair loss, irregular heart beat, sexual dysfunction, and depression.  

To prevent iron overloading, the body tightly controls iron uptake allowing absorption of only 1-2 mg of iron although dietary intake is around 7 mg for 1000 kcal.  Iron absorption is controlled because iron loss occurs only passively through squamous sloughing or blood loss (menstruation in women) but without a specific mechanism.  Genetic variants in iron intake or regulatory pathways can cause a loss of control resulting in hemochromatosis (aka iron overload).

Although with each meal some iron is absorbed, the majority of daily iron requirements are derived by recycling hemoglobin from red blood cells (RBCs) that have reached the end of their 120-day lifespan. Macrophages recycle hemoglobin iron to transferrin which is the carrier protein that facilitates safe iron transport in the plasma.  

Standard clinical assessment of iron status includes the measurement of serum ferritin, serum iron, total iron binding capacity (TIBC) and a complete blood count (CBC).  Serum ferritin is the most sensitive test for iron deficiency as ferritin represents the “stores” or reserve supply of iron in the body.  Ferritin is mostly found in the liver, spleen and bone marrow but the small amounts of ferritin in the plasma correlates closely with the amount of stored ferritin. Ferritin is mostly found in the liver, spleen and bone marrow but the small amounts of ferritin in the plasma correlates closely with the amount of stored ferritin.  The proteinaceous capsule of ferritin can hold 4,500 iron atoms, and catalyzes the oxidation of ferrous (Fe2+) to the less reactive ferric (Fe3+) form.

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