Vitamin B12 is an important vitamin required for proper functioning of nervous system. Deficiency of vitamin B12 leads to anemia (low hemoglobin) causing generalised weakness, tiredness and fatigue. In addition, it is an important cause of various neurological disorders.
Common manifestations of vitamin B12 deficiency:
1. Tingling or numbness of feet and hands (due to involvement of peripheral nerves)
2. Imbalance while walking (due to spinal cord involvement)
3. Memory impairment
4. Dementia (due to brain involvement)
5. Psychiatric disturbances
6. Uncommonly, fits, tremors, parkinsonism, etc have also been reported.
Who are prone to get vitamin B12 deficiency?
1. Pure vegetarians- Vegetarian diet is a poor source of vitamin B12, hence, symptoms of vitamin B12 deficiency are more common in veg people.
2. Those with gastro-intestinal disorders such as malabsorption (where food is not properly absorbed after eating, manifested by diarrhea), after certain gastric surgeries, etc.
3. Those with other autoimmune diseases such as hypothyroidism (lack of thyroid hormone), vitiligo (white patches on skin), myasthenia gravis (manifested by muscular weakness and fatigue). This is because presence of auto-antibodies may inhibit the absorption of vitamin B12 in the gut.
How to prevent vitamin B12 deficiency?
1. Eating diet rich in vitamin B12 can prevent vitamin B12 deficiency. All animal sources are excellent sources of vitamin B12, such as meat, chicken, fish, shrimps, eggs, etc. Since, vitamin B12 can be stored in the body for long, 1-2 servings per week may suffice in normal people. No plant source is a good and reliable source of vitamin B12.
2. Regular check ups- If you notice any of the symptoms of vitamin B12 deficiency (as listed above), consult your family physician/neurologist so that it can be diagnosed and treated early.
How to diagnose vitamin B12 deficiency?
1. Vitamin B12 level can be estimated in blood. It is a simple investigation available in most labs.
2. Further tests may be required to see the effects of vitamin B12 deficiency on nervous system or to ascertain the cause of vitamin B 12 deficiency.
How is vitamin B12 deficiency treated?
Once vitamin B12 deficiency is establilshed (after clinical exam and blood tests), patients are started on vitamin B12 supplements. Initially, injections are given, so as to prevent the problem of less absorption. Then, maintenance treatment is given with oral tablets of vitamin B12.
What is the outcome of treatment?
Most patients who are diagnosed and treated early show a good recovery, which, however, may be prolonged over weeks to months.
Dr Sudhir Kumar MD (Medicine) DM (Neurology)
Apollo Hospitals, Hyderabad