What is vitamin B12 and are you deficient?

Doctors have received new guidance on diagnosing B12 deficiencies following issues of under diagnosis and people being mistreated

The vitamin B12 helps keep the body's blood and nerve cells healthy and a lack of it can cause anaemia.

Around one in 20 people aged 65 to 74 are thought to be B12 deficient, while one in 10 people aged 75 and over are lacking in the vitamin, according to the NHS.

New guidance on how doctors diagnose B12 deficiencies was announced by The National Institute for Health and Care Excellence (NICE) on Wednesday, following issues of under diagnosis and people being mistreated.

So what is B12, what are the symptoms of a deficiency, and should you get tested?

What is vitamin B12?

B12 is a vitamin naturally found in animal products but it can also be added to foods.

The vitamin is important for the functioning of your nerves and the production of DNA in your cells.

B12 also works with folic acid to make red blood cells and other compounds that are needed for the cardiovascular and immune systems to work properly.

What are good sources of vitamin B12?

Most people consume enough B12 without consciously adding it into their diet, but older people, and those with specific dietary requirements, may need to boost their intake.

The following foods are considered a good source of B12:

  • Meat;

  • Fish;

  • Milk;

  • Cheese;

  • Eggs;

  • Foods fortified with B12, such as breakfast cereals and nutritional yeast.

What are the symptoms of a vitamin B12 deficiency?

The signs that a person is lacking in B12 vary from person to person, and are often not exclusive to a B12 deficiency, which can make it difficult to diagnose.

Common B12 deficiency symptoms include:

  • eyesight problems, such as blurred vision;

  • painful, inflamed or discoloured tongue;

  • balance issues;

  • a change in how you walk;

  • pins and needles;

  • signs of anaemia;

  • fatigue.

Who is likely to be deficient in B12?

People are more likely to have a B12 deficiency if they fall into one or more of the following categories:

  • following a diet low in B12, which can include vegans or people who avoid meat for religious reasons;

  • an allergy to some foods, such as eggs, milk or fish;

  • using nitrous oxide recreationally;

  • a family history of B12 deficiency or an autoimmune condition;

  • having certain health conditions, such as coeliac disease or gastric issues;

  • taking certain medicines, including colchicine, which is used to treat gout, or metformin, which is used to treat type 2 diabetes;

  • a history of abdominal or pelvic radiotherapy;

  • having had gastrointenstinal surgery, for example having the stomach removed or tissue being removed from the small intestine.

How is B12 deficiency diagnosed?

If a doctor suspects somebody may be deficient in B12 based on the list of symptoms, they will recommend a series of initial tests.

This will typically involve blood tests that look at the level of B12 in your blood, as well as whether you have healthy levels of haemoglobin (the substance that transports oxygen around the body) and how much folate (or folic acid) is in your blood.

What are the treatments for B12 deficiency?

Treatments for a lack of B12 depend on what is causing the deficiency, but most people can easily be treated with injections or tablets to replace the missing vitamins.

If somebody is anaemic, they will typically be treated with B12 injections, which are given by a nurse or GP.

If the deficiency is caused by diet, medical professionals may suggest taking vitamin B12 tablets in between meals and eating more vitamin B12-rich foods.

Should I get tested for B12 deficiency?

New guidance suggests that if a patient has at least one common symptom of B12 deficiency and one common risk factor, they should be offered an initial diagnostic test.

A doctor will decide whether or not to recommend a patient is tested for a B12 deficiency.

The information in this article does not constitute professional medical advice, and anybody with questions about vitamin B12 should consult a doctor.

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