Iron Toxicity

Introduction:

Iron is a metal that plays a vital role in the human body. This element cannot be produced and must be absorbed through foods or supplements.

High iron foods include^2,3:

Fortified cereals
Beef
Shellfish
Dried fruit
Large white beans
Spinach
Unsweetened chocolate
Quinoa
White button mushrooms
Squash/pumpkin seeds

Biotransformation^4,5:

Hemoglobin is an iron protein complex that is responsible for carrying oxygen and is eventually eliminated as waste. When broken down, hemoglobin transforms into several metabolites including bilirubin. The liver is primarily responsible for eliminating bilirubin and in the event that the liver is unable to such as disease or infection, the levels may increase and become toxic. High concentrations can lead to irreversible brain injury as well as alter eye/skin color.

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Toxicokinetics⁶:

While the toxicokinetics of iron poisoning is still under investigation, several factors have helped with potential discoveries. Iron is not a xenobiotic and is in fact highly reactive to other elements. As a result, many mechanisms have developed in order to prevent iron induced damage. With no exact mechanism for iron excretion, toxic doses lead to an over saturation of iron in the blood. The liver and gastrointestinal system are responsible for metabolizing and eliminating iron as well as the metabolites while also receiving potential damage.

Carcinogenicity⁷:

Iron is found to be carcinogenic in animal models and human experiments after discovery of target genes in iron-induced carcinogenesis

Target Organs^8,9:

Liver, heart and sometimes the pancreas as well as other endocrine systems

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Signs and Symptoms⁹:

Includes nausea, abdominal pain, diarrhea, dehydration and bloody/dark stool. Sometimes dizziness, change in pulse, low blood pressure, headache, fever, shortness of breath, change in skin pigment also occur.

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Genetic Susceptibility and Heritable Traits:

Hemochromatosis- gene mutation that alters the amount of iron in your body following absorption from food ingested and ultimately leads to iron overload
Anemia- some studies indicate that iron deficiency may have a genetic contribution
Sickle cell anemia- inherited abnormal hemoglobin that deprives the body of oxygen

Treatment:

Complete bowel irrigation- manually washing the body of excess iron
Chelation therapy- IV administration of chemical that binds to iron and helps elimination through urine

Biomarkers:

Below are common biomarkers and concentrations in relation to iron

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Essentiality and Deficiency:

Iron is responsible for oxygenating the blood, helps transform blood sugar to energy, supports the immune system as well as healthy skin, hair and nails. Too much or too little iron is easily noticeable and can have serious effects on the human body. Iron deficiency can lead to serious danger if not treated.

Below compares essentiality and deficiency