Vitamin B12 deficiency: symptoms & treatment

Overview: What is vitamin B12 deficiency?

Vitamin B12 plays an important role in the formation of red blood cells, the functioning of nerve cells and cell regeneration. Vitamin B12 is absorbed through food and can’t be produced by the human body. Symptoms often only occur after a lengthy period of deficiency, in particular in older people and vegans. Possible symptoms include fatigue, weakness, tingling in the feet and a burning tongue.

What are the symptoms of a vitamin B12 deficiency?

The main symptoms are fatigue and weakness. Paleness due to anaemia can also be a sign of a vitamin B12 deficiency, as can numbness or tingling in the feet and sometimes also the hands. Another symptom is a burning sensation on the tongue, which may appear red and smooth.

Other symptoms

• Mouth ulcers, diarrhoea, stomach cramps
• Weight gain
• Frequent infections, heavier or prolonged bleeding
• Unsteady gait, deterioration of vision, bladder disorders
• Non-specific symptoms such as lack of appetite, feeling weak, lethargy, problems with memory, nervousness and sleep disorders

Causes: How does a vitamin B12 deficiency occur?

If we follow a balanced diet we usually take in sufficient vitamin B12, which the body can store for several years. A vitamin B12 deficiency often builds up over time. Possible causes include:

• Insufficient uptake: poor nutrition in advanced age (e.g. owing to lack of appetite), vegan diet, anorexia, chronic alcohol consumption
• Uptake disorders: gastritis, operation to remove parts of the stomach or intestine, chronic inflammation of the bowel (e.g. Crohn's disease, ulcerative colitis, coeliac disease)
• Increased requirement: pregnancy, breastfeeding, newborn baby
• Long-term use of medication: medication to reduce the production of stomach acid, diabetes medication, epilepsy medication

A long-term deficiency can cause lasting damage, e.g. paralysis or dementia, as well as a higher risk of stomach cancer.

What foods are rich in vitamin B12?

A balanced and varied diet offers the best prevention. This will provide healthy people with sufficient vitamin B12. Good sources of vitamin B12 include animal products such as:

• Meat
• Fish
• Eggs
• Dairy products
  

Strict vegetarians and vegans can eat special foods enriched with vitamin B12 (e.g. oat milk or soya yoghurt). These can mostly be found in health food shops.

Vitamin B12 deficiency: When to see a doctor?

A doctor should definitely be consulted if symptoms (fatigue, numbness, burning tongue) persist over a prolonged period. Other possible causes, such as a deficiency in folic acid or iron, can then be checked at the same time.

Diagnosis by your doctor or in hospital

To detect a vitamin B12 deficiency, the doctor will take a blood sample and measure the vitamin B12 level. If a deficiency is diagnosed, the search for the cause will begin. If gastritis is suspected, a gastroscopy will be carried out.

Treating a vitamin B12 deficiency

Treatment for a vitamin B12 deficiency is dictated by the suspected cause. If the deficiency can’t be addressed by a varied diet, vitamin B12 supplements in the form of tablets or drops can be taken. If your body has problems absorbing the vitamin you can be given vitamin B12 injections.