We asked two experts what impact it has on our health, where we can get it from and, most importantly, what happens if don't have enough.
Why we need iron
"Most people are aware that iron helps to transport oxygen into the cells and so can affect our energy production and functionality, but few realise it also aids respiration, bone health, growth, the immune system, hair and skin formation and DNA synthesis.
"Low levels can impact upon our mobility, digestion, concentration, immune resistance, mood, digestion and appetite."
"Iron is needed for a number of highly complex processes that continuously take place in the body on a molecular level and that are indispensable to human life. The effects of deficiency can therefore be very far reaching.
"But this is just the icing on the cake as far as energy is concerned as iron is also needed to convert glucose into energy on our cells. Don’t do this properly, and you may find that you don’t get the energy you should from the food you eat.
"Iron is also needed to make many of the chemicals that allow our bodies to communicate and function properly. It acts as a co-factor for many enzymes, and so simply put, the body slows down without it.
"It’s always worth getting tested if you feel you aren’t firing on all cylinders. Vegans and veggies should pay special attention to this."
How much iron should we be having?
"It is important to pay particular attention to your iron intake if you are pregnant, breastfeeding or menstruating as each case will alter your personal needs, talk to your GP," said Poole.
So where can we get iron from?
The experts say we can find much of the iron we need from the food we eat. Poole recommended we incorporate red meat, liver, kidney, chicken, almonds, green leafy vegetables, avocado, pine nuts, apricots, pumpkin seeds, beans, pulses and whole-grains into our diets.
"Certain dietary habits can inhibit the absorption of iron such as excessive tea or coffee drinking, a high intake of sugar, overuse of antacids and too much alcohol," she added.
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How can you tell if you're low in iron?
Mackintosh said tiredness could be a key indicator: "The first thing that can suffer when we are low in iron is our energy level, largely because iron is an crucial component of our haemoglobin, the molecule that transports oxygen in our blood.
Without iron, oxygen isn’t delivered to the cells of the body as efficiently, often causing fatigue. This can be more noticeable when one exercises as oxygen demand increases exponentially."
Other indications of an iron deficiency could be poor sleep, fatigue, dizziness, brittle nails, headaches, digestive issues, depression, a red sore tongue, menstrual problems or anaemia, according to Poole.
"If you experience any of these symptoms it would be wise to consult your GP as Iron supplementation must be carefully monitored and I would always seek medical advice before taking any iron supplement product.," she said.
Should we take iron supplements?
According to Mackintosh, we shouldn't be raiding the chemist for iron supplements without careful consideration.
"A word of caution, only supplement if you need to as as much as we need iron, we don’t want too much and so it is important to stay in balance.
"Lastly, consider that iron requires the presence of many other nutrients in order for it to remain active in the body – b vitamins, zinc, copper and vitamin C should all keep it doing what it’s supposed to," she said.