Dr Amir Khan has highlighted five telltale indicators of a deficiency plaguing millions across Britain. In a clip titled '5 Signs you may be iron deficient', the NHS GP explored this widespread issue, which particularly impacts women.

"Iron deficiency anaemia is the most common type of anaemia," he explains. "It happens when your body doesn't have enough iron to make haemoglobin. Now that's the substance in your red blood cells that allows them to carry oxygen throughout your body.

"Now, normally, your body brings in a steady flow of iron from the food that you eat. Your body stores excess iron so it's available as needed to make haemoglobin. But, if you are not getting enough iron or it's being lost faster than it's being replaced, you will become deficient in iron.

"There are lots of different causes, but common ones include not getting enough iron in your diet, losing it through things like heavy periods. Ladies, heavy periods are not normal; get them sorted with your clinician.

"Gut illnesses like celiac disease and inflammatory bowel disease, and in some cases, iron deficiency anaemia can be a sign of underlying cancer. But here are five signs and symptoms you may be iron deficient."

As Dr Khan pointed out, women experiencing menstruation – particularly those with heavy flow – may develop insufficient iron levels. The NHS notes that expecting mothers can also be vulnerable.

Internal bleeding within the stomach and intestines represents another frequent trigger of iron deficiency anaemia. Symptoms of iron deficiency anaemia may include:.

The American Society of Haematology states that: "Iron is very important in maintaining many body functions, including the production of hemoglobin, the molecule in your blood that carries oxygen. Iron is also necessary to maintain a healthy immune system, muscles, cells, skin, hair, and nails."

It further notes that vegetarians, vegans, and others following diets lacking iron-rich foods may be vulnerable, alongside individuals who've had bariatric procedures, particularly gastric bypass surgery.

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Number one: tiredness. Now remember, iron helps your body make the red pigment in your blood that carries oxygen to all your organs. If you don't have enough iron, you won't be able to carry as much oxygen around your body, depriving it of vital energy, making you tired.

Number two: shortness of breath and chest pain. Now when haemoglobin, the red pigment in your blood cells, are low with iron deficiency, oxygen levels are typically low. This means that your muscles won't receive enough oxygen to do everyday activities such as walking. As a result, your breathing rate will increase as your body tries to get more oxygen in, resulting in shortness of breath. Your heart is also working harder to pump what oxygen you have around your body, and an unhappy, hard-working heart will tell you it's unhappy by giving you chest pain.

Number three: you have cracks in the corners of your mouth, here and here. Iron also plays a key role in skin health and wound healing, and if you are low you can get sores in the corners of your mouth. This is called angular cheilitis.

Number four: your nails are brittle or spoon-shaped. This condition is called koilonychia. Your nails look concave, like spoons, instead of growing flat.

And number five: restless legs. Iron deficiency can lead to restless legs syndrome as it can drop dopamine in your blood. This condition involves a strong urge to move your legs while they're at rest, or it may cause unpleasant crawling or itching sensations in your feet and legs. It's usually worse at night and can make it difficult to sleep. There are, of course, other causes for restless legs, but iron deficiency is one of them.

Now, good sources of iron in our food include liver or red meat, shellfish, or if you're vegetarian, legumes and pumpkin seeds are great. But if you're worried about iron deficiency anaemia, always speak to a healthcare professional.