Iron Deficiency - Diagnosis

Authored by Dr Jacqueline Payne, 26 May 2017

Patient is a certified member of
The Information Standard

Reviewed by:
Dr Hannah Gronow, 26 May 2017

A blood test is taken to look for the levels of iron (ferritin) in your blood and to make sure that you aren't also anaemic. If you are short of iron, your ferritin level will usually be low. A full blood count (FBC) will also be taken. This looks at the number, size and colour of your red blood cells. If you have iron deficiency, your red blood cells will be smaller and paler than normal. If there are also not as many red blood cells as normal then you also have iron-deficiency anaemia.

Sometimes it isn't possible to be absolutely certain that you are iron-deficient from the results of these two blood tests. In that case other tests may be needed, such as:

  • A blood film, in which blood is looked at down a microscope.
  • Measurement of vitamin B12 and folate.
  • Other tests of the body's iron stores - serum iron, transferrin (carries iron around the body), iron-binding capacity (IBC), for example.
  • Bone marrow biopsy.

Occasionally a trial of iron treatment will be recommended and the tests then repeated after a few weeks.

Whether or not you need other tests will also depend on whether the reason for you being short of iron is obvious. For example, if you are a woman in your twenties with heavy periods, it is unlikely you will need any other tests to confirm the reason for you having iron deficiency (although you would, of course, benefit from treatment to help your periods). If, however, you are in your sixties and also have indigestion as well as iron deficiency, your doctor will want to make sure that you don't have a condition such as a stomach ulcer or oesophagitis. Therefore, you may need further tests to look for such conditions.

Further reading and references

Hi new to the group. Trying to cut down on alcohol intake. Very difficult when you are staying and socialising with those who drink.

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