4 signs you have an iron deficiency

Green sickness

Back in the 17th century, doctors began to notice patients turning up with very strange symptoms indeed.

Made up of mostly young women and girls, the patients complained of odd symptoms such as apathy, pallor, and a notable greenish hue to their skin.(1) They also reported shortness of breath, headaches, and disruption to their appetites.

The ‘green sickness’ perplexed medics for a long time before being defined as ‘chlorosis’. As it turned out, the strange colour change was due to the women’s red blood cells.

Usually, your red blood cells look like concave little donuts. They are red in colour, with a pale area in the centre.

However, the women didn’t have enough of a special protein called haemoglobin, which increased the size of the pale area. The result? A pale, almost greenish tinge to the skin.

Eventually, doctors began to think this was caused by a lack of iron in the blood.

A few interesting treatments for green sickness

To treat the young women who presented with green sickness, doctors prescribed a variety of colourful remedies.

Before the iron deficiency hypothesis gained some ground, some medics were convinced - given that the patients were women and young girls - that the illness was caused by a state of ‘maidenhood’.

This goes back to Hippocrates, who may have got this one slightly wrong.

‘I advise young girls who experience such symptoms to marry as soon as possible: in fact when they become pregnant they are cured,’ he said in his work on the ‘Diseases of Women’.(2)

Thankfully, 17th century medics eventually twigged that the cause was iron deficiency and started to prescribe iron. Auguste Saint-Arroman, a French pharmacological writer, suggested that medicinal hot chocolate with iron filings might be the answer.(3)

Fortunately, things have moved on a lot since then! Chlorosis disappeared in the early 20th century, and our understanding of iron deficiency has greatly increased.

Related reading

• Mineral-rich foods: which whole foods to eat for your daily minerals
• Top 10 seeds to add to your diet

What is iron, and why do we need it?

Iron is a mineral. In the environment, it’s quite common - it makes up about 5% of the earth’s crust!(1)

In humans, iron is a dietary trace mineral. This means that we need a small amount for our bodily processes to work as they should. And while we don’t need much of it, the little that we do need is absolutely essential.

Our bodies contain about three or four grams of iron in total.(2)

Iron is a component of several important proteins in your body. But the main reason you need iron is to make red blood cells (sometimes called erythrocytes). About half of the iron within your body can be found within them. More specifically, the iron is stored in haemoglobin, a special protein in your red blood cells which helps them transport oxygen.(1)

As you go about your daily life, you use up or lose part of your stores of iron. This can happen when your red blood cells oxygenate other tissues in your body, or when your red blood cells need to be replaced with new ones. It can also occur if you lose blood through an injury.

For this reason, you need to keep topping up your iron stores through your diet.

What is iron deficiency anaemia?

Sometimes, doctors use the term ‘anaemia’ to describe low iron levels. However, you can also experience anaemia due to low levels of other minerals, such as copper.

Anaemia comes from the ancient Greek word for ‘lack of blood’. It essentially means that you don’t have enough haemoglobin or red blood cells, because your body lacks the iron needed to make them.(2)

It’s very common all around the world. In the developed world, it’s most often the result of not getting enough iron from your diet (or not being able to properly process what you do consume). However, pregnancy, or having very heavy periods, also contributes to anaemia in women.

In developing countries, diet only accounts for about half of anaemia cases. There are also other causes for iron deficiency, including disease (particularly malaria), blood loss from parasitic infections, and other nutrient deficiencies.