Overview:

Iron is an essential bioelement for most forms of life, especially humans. Iron is a necessary building block of crucial aspects of our bodies, the transport of oxygen, and the production of ATP (our energy source.). As essential as it is, when our amount of iron falls out of homeostasis (balance), it also can become one of the most dangerous and toxic substances resulting in ROS (reactive oxygen species). ROS is one of the major causes of most modern diseases – metabolic dysfunction. The following is an overview of iron and how it is both essential while in balance and toxic when not.

Key Benefits of Iron:

• Iron is necessary for most forms of life because of its ability to mediate electron transfer.
• Iron is necessary for the biogenesis of mitochondria as well as ATP production itself.
• Iron is necessary for red blood cells.
• Iron is the only mineral that carries oxygen.
• Iron is necessary for building structures in the body, including bones.

Key Risks of Iron:

• Iron toxicity – leaking into fluids, tissues, and organs. Generally caused by excessive iron consumption.
• Without enough bioavailable copper, iron builds up inside the mitochondria and thus inside the cells, which interferes with the mitochondria’s ability to make energy (Mg-ATP). ⁽¹⁾ 
• Dysregulated, unbound, excess iron is the most significant known source of oxidative stress and inflammation in the body.
• Iron catalyzes ROS generation and promotes lipid oxidation, contributing to atherosclerotic plaque instability. ⁽²⁾ 
• Too much iron can lead to osteoporosis.
• Iron deficiency is associated with obesity, and iron overload increases diabetes risk by directly damaging pancreatic cells, as well as by increasing insulin resistance.
• Iron’s ability to donate and accept electrons means that it can catalyze the conversion of hydrogen peroxide into free radicals. Free radicals can cause damage to a wide variety of cellular structures and ultimately kill the cell.
• Excessive iron feeds bacteria. Thus many defenses deprive bacteria or make it harder for them to attain iron within the body.
• ATP production can vary by at least 40% and as much as 96% if there’s too much iron in the cell and/or in the mitochondria.

Iron is a metallic chemical element with the symbol Fe and atomic number 26. It is the most common element on Earth, more common than oxygen. ⁽³⁾ 

Iron forms compounds mainly in the oxidation states +2 (iron(II), “ferrous”) and +3 (iron(III), “ferric”). Iron also occurs in higher oxidation states, e.g., the purple potassium ferrate (K2FeO4), which contains iron in its +6 oxidation state. Iron is by far the most reactive element in its group.

Iron’s ability to mediate electron transfer is key to iron’s importance. Iron acts as an electron donor in the ferrous state (Fe2+), while in the ferric state (Fe3+) it acts as an acceptor. Thus, iron plays a vital role in the catalysis of enzymatic reactions that involve electron transfer (reduction and oxidation, redox).

Iron is a crucial part of proteins and enzymes involved in numerous aspects of our life, from red blood cells down to our energy sources, the mitochondria. Our cells require iron to produce ATP via cellular respiration. Iron is essential to the transportation of oxygen. ⁽⁴⁾  

Well-nourished people in industrialized countries have ~4 to 5 grams of iron in their bodies, mostly in hemoglobin and myoglobin (∼38 mg iron/kg body weight for women and ∼50 mg iron/kg body for men) ⁽⁵⁾ 

Ferritin complexes contain the majority of the body’s iron in all cells but are most common in bone marrow, liver, and spleen. The liver stores of ferritin are the body’s primary physiologic source of reserve iron. ⁽⁶⁾