Iron: Overloaded & Inorganic

When we think of iron, we usually think we could use a bit more of it. This idea is deep seated in our culture. Iron was one of the first essential trace metals discovered. It is the most abundant element (by mass) on planet earth but hold that thought.

Virtually all microorganisms require iron for reproduction and growth. It also plays an important role within the mitochondria, for example in the iron sulfur clusters that facilitate the electron transport chain.

Iron has an exclusive relationship with oxygen by attaching to it and transporting itself to various tissues in the body where it is released to support oxidative metabolism. This is why people with iron deficiency anemia suffer from fatigue. Anemia by definition is a deficiency of haemoglobin which is the protein that carries oxygen.

We absorb around 15% of iron we consume and children absorb slightly less. However this varies according to whether it is heme (animal) or non heme. Furthermore, vitamin C taken alongside iron increases absorption dramatically. If you see a supplement with high iron and vitamin C, you should put it back on the shelf. More on that later.

In the 1940s, it was apparent that menstruating women were suffering from some iron deficiency anemia and this is when governments considered ‘fortifying' our everyday foods with iron like cereals and breads. This was the first mistake humans made with iron. Iron deficiency does not cause iron deficiency anemia in menstruating women in the vast majority of cases. Although hemoglobin levels may fall slightly, the body will correct itself by absorbing more iron from the diet.

In 1970, the real blow was delivered when the FDA proposed to triple the amount of iron in the diet. Instead of simply treating the few who actually had iron deficiency anaemia, governments decided to give everyone more of it. Sadly, this increase in fortification likely lead to the slow death of over a million people in North America with hereditary hemochromatosis; a genetic condition which causes the body to absorb more iron than usual.

In a healthy individual, consumption of both heme & non heme iron sources are not a particular problem for the body. As mentioned, the body absorbs exactly what it needs (unless hemochromatosis present which causes higher absorption). The reticuloendothelial system in the body is so efficient that over 95% of iron is recycled, theoretically humans could probably get by on much much less than the RDA (8 - 16mg).

However, in today's world with so much fortification, it is a different story. It is estimated that one half of ingested iron comes from fortified foods. Some cereals contain vast amounts of iron, like 24 mg per cup! Now imagine a child consuming this paired with a high dose vitamin C supplement. Vitamin C dramatically enhances iron absorption. The problem is, the iron added to foods is not natural. It is iron fillings and the body doesn’t know how to utilise it properly. Infact, in most cereals, a strong magnet will attract the iron and you will actually be able to see it.

When the body has too much iron, it stores it in the body, favouring organs like the liver and heart. The body has no effective way to remove it (unless you’re pre-menopause). According to the FDA, accidental iron overdose is one of the most common causes of poison death in children under 6 years old.

Under healthy circumstances, iron is tightly bound to organic components, referred to as chelation. This prevents iron from redox cycling. However, when present in excess, iron is toxic to cells. Free iron can be oxidised from ferrous to ferric iron for example. This is known as redox cycling. Iron redox cycles directly generate free radicals such as superoxide which damage cell integrity. Iron is really what we call a cumulative poison; it slowly builds up in tissues and is pro-oxidant, contributing to all aspects of aging.

Iron plays a role in all three stages of cancer, initiation, promotion and progression because of its redox cycling capabilities. Cancer tumours have a fascinating appetite for iron, clearly demonstrated by the increase in transferrin receptors on their surface (the transport protein for iron). The more receptors, the more iron it can take up. In this way, cancer uses a starve and destroy approach leaving the surrounding tissue ‘anemic’.

The first step in reducing excess iron is removing the inorganic sources. Take a minute to look at the back of your everyday foods, be it cereals, breads and flours etc. You will see a ubiquitous use of iron. All those mg add up and the reality is, you don’t need any of it. The science behind iron fortification is a complete shambles.

Second, because iron is very difficult to chelate out of the body, donating is the only way to effectively offload a significant amount. Although iron is stored in the tissues, the majority lies in the blood (70-80% in the RBCs). Assuming you don’t have any pre-existing health conditions that would put you at risk, I would encourage you to donate. It is recommended that men donate 4 times a year and women 2 times up until menopause, at which point they can comfortably increase to 3 or 4 times. The added bonus of donating is that you might live a bit longer (yes donors really do), not to mention the obvious help it will bring to someone in need.

Thirdly and perhaps most importantly, you should increase bioavailable copper in the body. Copper is to iron as to what magnesium is to calcium. They are both highly reactive and structurally similar transition metals. Copper helps activate ferroportin, the door allowing some free excess iron out and helps put iron in the right places. Without sufficient bioavailable copper, free iron will roam around the body causing havoc. Most copper leaves the liver within the ceruloplasmin (CP) (probably the most fascinating molecule or enzyme in the body). The absence of CP leads to iron accumulation in the pancreas, retina, and brain, indicating that the ferroxidase activity of circulating CP is critical for normal iron homeostasis. We also know that copper absorption may be increased during states of iron deficiency, as suggested by increased metallothionein (Mt) mRNA expression, reinforcing their synergistic relationship. My favourite sources of bioavailable copper are shitake mushrooms, bee pollen and liver. The latter is a perfect example of iron and copper in balance.