Sign In
  • ENG

Vitamin B12 deficiency: Know the symptoms and how to address them

Vitamin B12 helps make your DNA and your red blood cells. © Shutterstock.

Vitamin B-12 is crucial to produce blood cells. Symptoms of vitamin B-12 deficiency include fatigue, low mood, and nerve problems.

Written by Longjam Dineshwori |Updated : December 23, 2019 11:20 AM IST

Vitamin B12 is an essential nutrient to stay healthy. It helps make your DNA and your red blood cells, and supports the nervous system. The deficiency of this nutrient can lead to both physical and psychological problems.

Symptoms of vitamin B12 deficiency

Vitamin B-12 deficiency causes lack of blood cells, which are needed to get oxygen around the body. Here some symptoms of vitamin B12 deficiency and their causes. These signs can help you identify the deficiency and seek treatment. You can also get a blood test to check your vitamin B12 level.

Also Read

More News

Tingling hands or feet

If you have vitamin B-12 deficiency, you may feel tingling in the hands or feet. This is because absence of vitamin B12 leads to nerve conduction problems or nerve damage. The vitamin helps produce a substance called myelin in the nervous system. Myelin coating protects the nerves and helps them transmit sensations. Vitamin B-12 deficiency may affect production of myelin and cause damage to the nerves.

Problems are more common in peripheral nerves and so vitamin B12 deficiency may cause tingling in in the hands and feet.

Numbness in the feet and limbs

When not treated in the early stages, peripheral nerve damage can also lead to movement problems. People with vitamin B12 deficiency may feel numbness in the feet and limbs and find it difficult to walk without support. They may also experience muscle weakness and diminished reflexes.


Vitamin B-12 is essential for the production of red blood cells. Lack of it in the body may lead to development of jaundice. You get jaundice when your body is not able to produce enough red blood cells, and your skin look pale.


Lack of red blood cells, or megaloblastic anaemia, due to vitamin B-12 deficiency may also make a person feeling fatigued. When there are no enough red blood cells to carry oxygen around the body, a person may feel extremely tired.

Fast heart rate

Another symptom of vitamin B12 deficiency is fast heart rate. When there are lesser number of red blood cells in the body, the heart may start to beat faster to make up for it. This is because your health is trying to push a higher volume of blood around the body more quickly to ensure that enough oxygen reaches all the organs.

Loss of appetite

Vitamin B12 deficiency may affect the digestive tract and cause loss of appetite. This may further lead to weight loss in the long term.

Tips to address the deficiency

You are also likely to develop vitamin B12 deficiency if you have Atrophic gastritis (thinning of your stomach lining); Pernicious anaemia (body fails to absorb vitamin B12); problems in small intestine (Crohn's disease, celiac disease); immune system disorders ( such as Graves' disease or lupus); or taking certain medications that disrupts the absorption of B12.

The human body does not produce vitamin B12, so you must get this nutrient from your diet. Vitamin B12 can be obtained from animal-based foods as dairy products, eggs, fish, meat, and poultry or from supplements. You need eat such foods regularly to fulfil the need of this nutrient in your body.

Following a vegan diet can also cause vitamin B12 deficiency. So, if you are a vegan then you can add fortified cereals, plant milks, bread, nutritional yeast to your diet or take supplements to meet the Vitamin B12 needs in your body.

How much vitamin B12 one should get?

It depends on your age, habits and medical conditions.

Here are the average recommended amounts as per age:

Infants (up to 6 months): 0.4 mcg

Babies (7-12 months): 0.5 mcg

Children (1-3 years): 0.9 mcg

Kids (4-8 years): 1.2 mcg

Children (9-13 years): 1.8 mcg

Teens (14-18 years): 2.4 mcg

Adults: 2.4 mcg (2.6 mcg per day if pregnant and 2.8 mcg per day if breastfeeding)

Total Wellness is now just a click away.

Follow us on