This test measures how much iron is in your blood with the aim of identifying iron deficiency anaemia or iron overload syndrome (haemochromatosis)
The symptoms of too much or too little iron can be similar - fatigue, muscle weakness, moodiness and difficulty concentrating.
A raised result can mean that you have iron overload syndrome, an inherited condition where your body stores too much iron, or that you are over-supplementing or that you have a liver condition.
A low result can mean that you are anaemic or are suffering from gastro-intestinal blood loss (or other blood loss). Anaemia is also very common in pregnant women.
Total iron binding capacity (TIBC) is a measure of the amount of iron that can be carried through the blood.
A raised TIBC result usually indicates iron deficiency whereas low TIBC can occur with iron overload syndrome (haemochromatosis).
Transferrin is made in the liver and is the major protein in the blood which binds to iron and transports it through the body.
Low levels of transferrin indicate iron deficiency while high levels indicate iron overload.
Ferritin is a protein which stores iron in your cells for your body to use later. Measuring ferritin levels gives us a good indication of the amount of iron stored in your body.
Low levels of ferritin can indicate anaemia which can be caused by excessive or chronic bleeding, poor absorption of iron or too little iron in the diet.
Raised ferritin levels can indicate iron overload syndrome (haemochromatosis) or any kind of liver damage. It is also a marker of infection and inflammation.