A urine and venous blood sample test as a second line test for vitamin B12 deficiency as recommended by the B12 Society for those who have symptoms that may be due to vitamin B12 deficiency and have had the B12 Deficiency First Line Test. The cost includes a £9.99 donation to the B12 Society.
It is advised not to take any B12 supplements or foods or drinks fortified with B12 for 4 months before testing as serum B12 may be misleading. It should also be remembered that reference ranges vary and that symptoms can occur even when the B12 levels are in the “normal” range. A second line test may be considered for further information but will require urine sample and a venous blood sample (from your arm)..
B12 Deficiency (B12 Society Second Line Test)
A second line test for further information but will require urine sample and a venous blood sample (from your arm).
- Serum active B12 (holo TC)
- Serum Methylmalonic Acid (MMA)
- Urine Methylmalonic Acid (MMA)
- Serum total Homocysteine
- Intrinsic factor Antibodies
- Parietal Cell Antibodies
What is Vitamin B12 and why is it important?
Vitamin B12 is part of the B complex of vitamins alongside vitamin B9 or folate. They are essential vitamins which means that the body is unable to make them itself and must obtain through our diet. Vitamin B12 is required for the formation of red blood cells as well as for forming a coat around nerve cells called myelin and deficiency can cause a range of symptoms and effects.
Causes of Vitamin B12 Deficiency
Several groups of people may be at an increased risk of vitamin B12 deficiency:
- Vegans face a risk of vitamin B12 deficiency, as their diet excludes animal-sourced food products. Pregnancy and lactation can worsen deficiency in vegans. Unless a vegan diet is carefully planned, it is difficult to get enough vitamin B12 through plant foods alone. For this reason, it is recommended for those following vegan diets to supplement with B12.
- Pernicious anaemia may be due to a lack vitamin B12. Pernicious anaemia is an autoimmune disease that affects the blood. Patients with this disorder do not have enough intrinsic factor (IF), a protein in the stomach that allows the body to absorb vitamin B12.
- Gut problems: small intestine problems, for example, someone with a surgically shortened small intestine. Crohn’s disease is also a risk factor for vitamin B12 deficiency due to frequent involvement of the terminal ileum.
- Stomach Problems. Gastritis, coeliac disease, and inflammatory bowel disease (IBD) may lead to a deficiency because these conditions reduce nutrient absorption.
- Alcohol. Chronic alcohol abuse may affect vitamin B12, as those who do may not absorb nutrients efficiently.
- Diabetes. Those who are treated with metformin should have their B12 levels tested by their healthcare professional regularly. This is because metformin reduces the absorption of vitamin B12.
- Medications. Some medications can also cause low vitamin B12 such as proton pump inhibitors and H2 receptor agonists like Omeprazole which are often used for gastritis and peptic ulcer disease.
Treatment of Vitamin B12 Deficiency
Treatment for vitamin B12 deficiency includes oral vitamin B12 supplements or vitamin B12 injections once any underlying causes have been excluded or treated.
Monitoring when on treatment 3-4 monthly – Do not retest B12
- Serum Folate
- Ferritin (ideally after fasting for 12 hours)
- Vitamin D (25 OH Vitamin D)
If you are concerned about your B12 levels, please discuss your concerns and the results of any blood tests with your GP or usual healthcare professional.