Our tests look for three of the most common causes of anaemia: deficiency of iron, vitamin B12 or folate.

Iron deficiency anaemia:

Haemoglobin contains iron and cannot be produced without it. When iron levels are low our bodies make less haemoglobin and this can lead to anaemia. Iron deficiency anaemia can occur from lack of iron in the diet, decreased absorption of iron in the gut or loss of blood. It is relatively common in women before the menopause due to the blood loss during menstruation. It is important to find out the reason for iron deficiency anaemia as it could indicate undetected blood loss particularly from the gut. For this reason, if our test finds iron deficiency anaemia we will recommend discussing the result with your GP.

Vitamin B12 or folate deficiency anaemia:

Vitamin B12 and folate are needed by our body to make red blood cells. Lack of either of these vitamins can lead to anaemia. Vitamin B12 or folate deficiency anaemia can occur from lack of dietary vitamin B12 or folate, decreased absorption in the gut or as a result of some long-term medical conditions or medications. Sometimes vitamin B12 deficiency can be an indication of an condition called pernicious anaemia. This condition stops vitamin B12 from being taken up in the gut and often needs to be treated with vitamin B12 injections. Deficiency of vitamin B12 or folate can lead to other effects as well as anaemia. For these reasons, if our test finds vitamin B12 or folate deficiency anaemia we will recommend discussing the result with your GP.

Other causes of anaemia:

There are a range of other medical conditions that can lead to low levels of haemoglobin. These include kidney disease, inflammatory disease, long term infection, liver disease, cancer and some inherited conditions. If our test finds that you have anaemia but this does not seem to be due to iron, vitamin B12 or folate deficiency, we will recommend that you discuss the results with your GP.

Haemoglobin: This is a measure of the concentration of haemoglobin in your blood sample. This will tell you whether or not you have anaemia. Other names for this test include Hb and Hgb. The units of measurement for haemoglobin are grams per litre (g/L).

Ferritin: ferritin is a protein that is used by the body to store iron inside of cells. The amount of ferritin in the blood can indicate how much iron is stored in the body. Low levels of ferritin can be an indication of iron deficiency. The units of measurement for ferritin are micrograms per litre (ug/L).

Transferrin saturation: Transferrin is a protein that transports iron in the blood around the body. Transferrin saturation is a measure of the amount of transferrin that is carrying iron. Low transferrin saturation can suggest that the transferrin does not have a lot of iron to carry. This can be an indication of iron deficiency. Other names for this test include TSAT and TS. Similar tests include total iron binding capacity (TIBC) and unsaturated iron binding capacity (UIBC). The units of measurement for transferrin saturation are percentage (%).

Active vitamin B12: Vitamin B12 is transported in the blood attached to two different proteins called haptocorrin and transcobalamin. Vitamin B12 attached to transcobalamin is the active form of the vitamin. This test measures this active portion of vitamin B12. Low levels can indicate vitamin B12 deficiency. Measuring the active portion of vitamin B12 is thought to be a better marker of vitamin B12 deficiency than measuring all of the vitamin B12 in the blood. Other names for this test include Active B12, HoloTC and holotranscobalamin. The units of measurement for active B12 at picomoles per litre (pmol/L).

Folate: This is a measure of the amount of folate in plasma. Plasma is the liquid part of the blood. Plasma folate is a marker of folate intake and low levels can indicate a deficiency of folate. Other names for this test include vitamin B9 and folacin. The units of measurement for this test are micrograms per litre (ug/L).

Our anaemia tests do not have reference ranges. Instead, we have cut-off values below which a measure can be considered low. These cut-off values follow the recommendations of the British Society for Haematology. 

Haemoglobin: below 120 g/L for females and below 130 g/L for males indicates anaemia 

Ferritin: below 15 ug/L suggests iron deficiency 

Transferrin Saturation: below 16% suggests iron deficiency 

Folate: 3 ug/L or below suggests folate deficiency 

Active vitamin B12: below 38 pmol/L suggests vitamin B12 deficiency 

If our tests find that you have low levels of iron, vitamin B12 or folate but you do not have anaemia, we will suggest that you could try changes to your diet.

Iron:

Dietary sources of iron include: kidney beans, chickpeas, edamame beans, dried apricots, raisins, dates, pistachio nuts, cashew nuts, almonds, red meat, liver, oysters, mussels, clams, canned sardines or tuna. Absorption of iron from plant-derived foods can be improved by consuming food or drink containing vitamin C such as oranges or orange juice, melon, strawberries or spinach.

Vitamin B12:

Vitamin B12 is found in animal-derived foods such as meat, fish, shellfish, milk, cheese, yoghurt and eggs. It can be more challenging to find non-animal derived foods containing vitamin B12 and supplements are often recommended for people following a plant-based diet. Dried nori (seaweed) sheets and tempeh are potential dietary sources of vitamin B12 but the content does vary between products. Fortified foods such as breakfast cereal, nutritional yeast and yeast extract also commonly contain vitamin B12.

Folate (vitamin B9):

Good dietary sources of folate include: green vegetables such as broccoli, spinach or brussels sprouts, kidney beans, chickpeas, peanuts, sunflower seeds, fresh fruit, fruit juice, whole grains, wholemeal bread, seafood or eggs. Vitamin B9 supplements usually contain folic acid rather than folate. Folic acid is more easily absorbed into our body and is then turned into folate. Fortified foods such as breakfast cereals also contain folic acid.

Mean cell volume, also known as MCV, is a measure of the average size of your red blood cells. This can be a useful indicator of the cause of anaemia. MCV is not stable in blood samples and so it is not a suitable test for samples that take more than a few hours to reach the laboratory.