An essential dietary mineral used by red blood cells, iron forms a crucial part of hemoglobin, a protein which helps carry oxygen to all the cells of our body.
High iron levels increase the secretion of hepcidin—the hormone that regulates iron levels in the body—which decreases iron absorption. Alternately, when the body has low iron levels, the secretion of hepcidin is reduced, resulting in increased iron absorption.
An excessive use of iron supplements is the most likely cause of an overdose of iron and can cause severe iron poisoning.
What Is Iron Toxicity?
Iron toxicity results from excessively high levels of iron in the body. It can be sudden or gradual and can lead to serious health problems caused by chronic iron overload disorders, accidental overdoses or taking high-dose supplements for a long time.
Normally, free iron circulated in the bloodstream binds to proteins (called transferrin) that make it harmless. However, high levels of iron increase the free iron in the blood, which then becomes a pro-oxidant (the opposite of antioxidant) and can damage the cells.
Causes Of Iron Toxicity
1. African Iron Overload: This is a type of dietary iron overload, which was first seen in Africa where homemade beer was brewed in iron vessels. It is caused by the high levels of irons in drinks and foods.
2. Hereditary Hemochromatosis: A genetic disorder in which excessive absorption of iron from food takes place.
3. Iron poisoning: This can result when people (usually children) take an overdose of iron supplements.[4,5]
Health Problems Due To Iron Toxicity
- Animal and clinical studies show that iron overload may lead to cancer.[6,7]
- Clinical studies have shown that heme iron from supplements or red meat could increase the formation of cancer-causing N-nitroso compounds in the digestive tract.[8,9]
- Excessive levels of iron in the blood can also stimulate the growth of bacteria and viruses causing infection.
How To Minimize Iron Toxicity?
If you are genetically prone to increased iron absorption or have taken an excess of iron supplements, you can minimize your health risks by following these tips.
- Avoid using iron cookware.
- Do not take vitamin C supplements with foods that are rich in iron as it increases iron absorption in the body.
- Donate blood once in every three months.
- Reduce your intake of iron-rich foods such as red meat.
- Never take iron supplements unless recommended by your doctor.
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