A doctor’s guide to iron deficiency

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Iron deficiency is very common, but many people have symptoms for years before discovering the cause. Dr Samuel Menon, Lead GP at Livi, answers your questions

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Iron is one of our body’s metabolic giants. It’s one of the most abundant metals on our planet, with the paradox being that we don’t always have enough of it. Iron deficiency is the most common nutritional disorder in the world, affecting around 500 million people worldwide.

Am I iron deficient?

The only way to really know if we’re running low on iron is to have a blood test. If you were definitely iron deficient, this would reveal a ferritin level below 15mcg/L – ferritin is a protein that binds with iron in our bodies to give us an indication of the body’s stores. That said, you may have some signs or symptoms of iron deficiency:

  • Fatigue
  • Difficulty concentrating
  • Feeling irritable
  • Pallor (paleness)
  • A sore tongue
  • Dry or rough skin
  • Dry and damaged hair, or hair loss
  • Nail changes
  • Painful cracks at the corners of the mouth
  • Headache
  • Tinnitus (ringing in the ear)
  • Iron-deficiency anaemia

We mostly worry about iron deficiency because it can lead to an anaemia if not corrected. Very common symptoms of iron deficiency anaemia are a little more noticeable and tend to include:

  • Fatigue
  • Breathlessness

And sometimes:

  • Chest pain
  • No symptoms at all

What are the causes of low iron?

There are several causes. Our modern-day diets are often partly to blame although they’re rarely the single cause. Our diets aren’t always rich in sources of iron, particularly if we’re vegetarian or vegan (animal sources contain iron in a form that is more easily absorbable). In premenopausal women, the most common cause of iron deficiency is heavy periods. In every other adult, it’s blood loss from the gastrointestinal tract. More specific causes include:

  • Aspirin
  • NSAIDs, like ibuprofen and naproxen
  • Pregnancy (physiological requirements are 3 times that of menstruating women)
  • Gastric ulcers
  • Coeliac disease
  • Cancer

We mostly worry about iron-deficiency anaemia when we don’t know what the cause is, because it might signal blood being silently lost from the bowel, which would need further investigations to exclude cancer.

What can I do if I think I have low iron?

If you’re otherwise healthy, it’s still fairly unlikely your iron level will be low; an estimated 3% of women and 8% of men in the UK have an iron-deficiency anaemia, although we can have low iron without being anaemic. If you think there’s a chance, book an appointment with a Livi doctor for a conversation about it. Beyond a simple blood test, a doctor will tailor their assessment to include you, not just the number – personal context is everything.

What iron-rich foods can I add to my diet?

Doctors find it difficult to write articles that don’t include some advice about eating well. Why? – because it’s so important, and usually a part of our lifestyle we can improve or make simple yet effective changes to. A balanced and nutritious diet is a cornerstone of healthy living more generally, but rich sources of iron are found in many different foods.

  • Red meat including beef, lamb and pork
  • Fish and poultry
  • Pulses and legumes like beans, peas and lentils
  • Dark green, leafy vegetables like spinach, cabbage and broccoli
  • Tofu
  • Nuts and seeds

Sources of vitamin C also help by increasing the amount of iron absorbed by the gut. But when it comes to longevity, many experts would tell you to eat less, and mostly plants. The message being, don’t eat steak every night to ward off low iron.

What will the doctor do if I have low iron?

It depends on your personal context: your age, sex, medical history, any medication you’re taking, whether you have symptoms of iron deficiency, and what those symptoms are. In general terms, we’ll do the following:

  1. Establish if you do have low iron or an iron-deficiency anaemia
  2. Find out why
  3. Treat and manage the cause

Firstly, we’d organise a blood test to establish if you are iron deficient; but if you have symptoms of some kind or a medical history of note, we might perform several additional tests. For example, if you told us you were tired a lot of the time recently, we’d undertake a screen for other causes of tiredness, like an underactive thyroid. If we then find that you are indeed low in iron, or that you have an iron-deficiency anaemia, we’ll investigate the cause.

This may not be necessary if for example, you’re a premenopausal woman with heavy periods, but we may refer urgently for a colonoscopy if you’re a man. Once we’ve made an assessment, we’ll usually prescribe iron supplements and manage the cause. So in the case of heavy periods, this would be a discussion around contraceptive methods which can help significantly.

What supplements are available, and should I take iron anyway?

There are several formulations that we commonly use: ferrous sulphate, ferrous fumarate, and ferrous gluconate. There are reasons doctors may choose one over another, but they’re all effective. Side effects commonly include constipation, diarrhoea, abdominal discomfort and nausea, but people often tolerate them well after some time, and the dose is adjustable. People also report dark stools.

In general, we wouldn’t recommend supplements unless we’ve identified a particular deficiency or you’re particularly at risk of one. If you’re unsure, speak with us and we can advise you further.

What are the other symptoms of bowel cancer?

Iron-deficiency anaemia is a finding for some, but symptoms you should speak to a doctor about include abdominal pain, bleeding from the bottom, unexplained loss of appetite or weight loss. But having these symptoms does not mean you have cancer, and we can reassure you if that’s the case.

What are the other symptoms of anaemia?

There are many causes of anaemia, with iron deficiency being just one of them. Anaemia can also be related to kidney problems, B12 or folate deficiency, or genetic factors (for example, in people with thalassaemia). Symptoms again include pallor, fatigue, breathlessness, and headache.

What is pernicious anaemia?

This is an autoimmune condition that prevents B12 from being properly absorbed in the stomach, which ultimately causes an anaemia. It’s relatively rare.

What if I’m worried my child might have low iron?

Symptoms of iron deficiency in children can be similar, but the causes tend to be different, with nutrition being more relevant. Speak to your health visitor, midwife, doctor or us here at Livi.

This article was written by Dr Samuel Menon, Lead GP at Livi.

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