Joseph R. Anticaglia MD
Medical Advisory Board
Iron is present in every living plant and animal cell. Without iron, virtually all life would cease to exist.
Although this trace mineral is found in every cell of the human body, most of it is concentrated in two proteins: hemoglobin in red blood cells (RBCs) and myoglobin in muscle cells.
The Important functions of Iron are often overlooked:
- Iron is needed by red blood cells to transport oxygen into the tissues of the body and the removal carbon dioxide from the body.
- Iron is the pivotal element in the manufacturing of hemoglobin and myoglobin
- It’s an essential component (cofactor) for many enzymes which help speed up chemical reactions in the body and other functions.
- Iron is needed for growth — to make new cells, amino acids, hormones
- It’s important for energy production. It works with enzymes to convert foods to energy
Recycling of Iron
Red blood cells live for about 120 days. The liver and spleen salvage the iron from the dead RBCs and send them back to the bone marrow to make hemoglobin for future use.
Iron is carefully managed so that it does not roam free in the body. Left uncontained, it will form free radicals that lead to inflammation associated with cancer, cardiovascular disease and diabetes.
Hormone Factor in Iron Absorption — “Hepcidin”
If there’s too much iron in the diet, iron absorption declines. If there’s not enough iron in the body due to dietary deficiency or an increase need for this mineral as in blood loss or pregnancy, iron absorption increases.
Hepcidin is the hormone secreted by the liver that helps regulate the concentration of iron in the blood. Too much iron in the system — Hepcidin is secreted. Too little iron in the body — Hepcidin is suppressed.
Dietary Factors in Iron Absorption
Iron exists in two forms in food: Heme and non-heme iron.
Heme is the iron containing part of hemoglobin and myoglobin found in foods such as red meats, poultry and fish. It’s absorbed more readily than non-heme iron.
Non-heme iron is the dietary iron found in plant foods like beans, green leafy vegetables and nuts. It’s not associated with or bound to hemoglobin. Vitamin C significantly improves the absorption of nonheme iron.
Inhibitors of Iron Absorption. Some substances stymie the absorption of iron.
- Tea, especially black tea and coffee (tannins)
- Dairy products and products rich in calcium (calcium and phosphorous)
- Nuts, seeds, legumes and grains (phylates)
- Medications
‘Takeaways’ — The most important reason we need iron is that it works to transport oxygen from the lungs to the tissues throughout the body. To accomplish this vital job it assists in the production of hemoglobin and myoglobin.
You’re going to feel tired and run down if the body is deficient in iron — the body doesn’t get enough oxygen.
Dietary iron is stored as ferritin in the liver and muscle. Ferritin level is a laboratory test used to help diagnose iron deficiency anemia.
Although we have just 3 to 4 grams of iron in our bodies, this metal is priceless.
References
- Nazanin Abbaspour et al; Review on Iron and its Importance for Human Health; J Res Med Sci, Feb 19, 2014.
- NIH; Iron; Feb 17, 2016.
- CDC; Iron; CDC Recommendations to control and prevent iron deficiencies in the U. S. 10/5/1998.
- A West and P Oates; Mechanism of Heme Iron Absorption; World Journal of Gastroenterology; July 24, 2008.
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This article is intended solely as a learning experience. Please consult your physician for diagnostic and treatment options.