Home › Blood tests › Iron and ferritin
Iron and ferritin
testing in London
Dr Rhea has a particular interest in iron deficiency and anaemia. This is the test she is asked about most.
You can be iron deficient with a normal blood count
This is the part that catches people out. A standard full blood count can look perfectly fine while your iron stores are running on empty, because the body protects your haemoglobin first and depletes the reserves behind it. Ferritin is the marker that shows the reserves, and it is not always included.
That is why so many people are told they are not anaemic and continue to feel exhausted. They are not imagining it, and they have not been fobbed off deliberately. The test that would have shown it was simply not the one that was done.
Dr Rhea has a particular clinical interest in iron deficiency and anaemia, and it comes up constantly: heavy periods, vegetarian and vegan diets, pregnancy and the year after it, endurance training, and gut conditions that affect absorption. It is one of the most treatable causes of feeling permanently worn out.
What happens
Testing the stores, not just the count
The £89 consultation covers the appointment. Ferritin with a full blood count is £115. The fuller iron status profile is £140. Both come back the next working day.
What gets looked at
More than a standard blood count.
Reading it properly
Where the interpretation matters.
Who this is for
Common reasons to check your iron
Heavy periods
The single commonest cause of iron deficiency in women, and frequently accepted as normal for years.
Exhaustion with no obvious cause
Tired constantly, breathless on stairs you used to manage, no energy for anything after work.
Vegetarian or vegan diet
Plant iron is absorbed less efficiently. Not a problem in itself, but worth checking rather than assuming.
Pregnancy, or the year after
Demand rises sharply and stores are often depleted well after the birth.
Endurance training
Running and cycling volume increases iron losses. Common in people who cannot understand why performance has stalled.
Restless legs, hair loss, brittle nails
Less obvious signs that regularly turn out to be low iron rather than anything else.
Iron deficiency has a cause, and finding the cause matters as much as correcting the number. Persistent deficiency in men, or in women after the menopause, needs looking into properly rather than simply supplementing.
Questions
Things people ask us
Why was I told I am not anaemic when I feel like this?
Because anaemia and iron deficiency are not the same thing. Anaemia means your haemoglobin has fallen. You can have empty iron stores with a haemoglobin that is still normal, and feel every bit as exhausted. Ferritin is the marker that shows it, and a basic blood count does not include it.
Do I need to fast?
No, fasting is not required. It is best to have the sample taken when you are well, because a recent infection or any inflammation pushes ferritin up temporarily and can make low stores look normal. Mention it if you have been unwell recently.
Should I just take a supplement instead?
Supplements are cheap and easy, but taking iron you do not need is not harmless, and treating a deficiency without asking why it happened can leave the actual cause unfound. Testing first tells you whether you need it, how much, and for how long.
How long before I feel better?
Usually some improvement within a few weeks of starting treatment, but replenishing your stores properly takes considerably longer, often three to six months. The GP will tell you when to retest rather than leaving you guessing. If the picture needs more detail, the iron status profile at £140 adds iron, TIBC and transferrin saturation.
Related
Often tested at the same time
One of the most treatable causes of exhaustion
Test the stores, not just the count.