Vitamin B 12 also called Cyanocobalamine, has the largest molecule compared to all other vitamins.
Vitamin B12 is plays a major role to synthesis
1) Methylmalonyl CoA to Succinyl CoA
2) 5-Methyltetrahydrofolate and Homocysteine to Tetrahydrofolate and Methionine
VITAMIN B12 IS NECESSARY FOR
Myelinogenesis , its co-substrate in various cellular reacations involved in methylation synthesis of nucliec acid and neurotransmitters, active metabolites of vitamin B12 are required for methylation of homocystine which is required in formation of methionine, which is required for metabolism of many monoamine neurotransmitters, thus it plays a mojor role in proper nervous system formation and its functioning.
DNA synthesis thus helps in proper maturation of neucleus and cells.
Metabolism of amino acid and fatty acids in cells.
DEFICIENCY OF VITAMIN B12
Its deficiency can cause severe damage to nervous system
As it is essential for each and every cells, its long deficiency may cause damage to organs and may result other metabolic disorders.
General symptoms it present on slightest decrease below its normal range are.
- General Weakness
- Dyspnoea on Slightest Exertion
- Pain in Limbs
- Weak memory
As it is essential for each and every cells, its long deficiency may cause damage to organs and may result other metabolic disorders
ESTIMATED DAILY REQUIREMENT OF VITAMIN B12
- Infants upto age of 12 months its from 0.4μg/day to 0.5μg/day
- Children upto 13yrs of age is 0.9μg/day to 1.8μg/day
- Person above 14yrs of age is 2.0μg/day
- Pregnant Women is 2.6μg/day
- Lactating Women is 2.8μg/day
- Infants upto age of 12 months its from 0.4μg/day to 0.6μg/day
DIETARY SOURCES OF VITAMIN B12
Meat and Fish are rich source
Except for Arachea and Bacteria no other In cellular life forms has genes to express protiens that can produce or synthesis vitamin B12 De Novo.
Vit B12 is absorbed in small intestines and there are bacteria which produce Vit B12 in colon so , even though its produced by microbial flora of intestine of humans it is difficult to absorb.
Ruminating vegetarian animals like cow buffalo etc they can consume their gut Vit B12 produced by gut bacteria when they bring back up the food to chew and deglute again, also they pick it up when they graze grass along with the soil at roots of grass they get ample of bacteria which provide them with Vit B12.
There are very few vegeterian dietary sources of Vit B12 and also they are very low in Vit B12 quantity,
So vegetarian are more prone to Vit B12 deficiency,
Major reason for deficiency is insufficient dietary intake of Vit B12.
In many cases malabsorption and lack of factors required for binding Vit B12 causes its deficiency,
Infants feeding on mother with low vitamin B12 may develop deficiency.
In vegan population incidence of vitamin B12 deficiency is estamited to be upto 80%
SOURCES OF VITAMIN B12 FOR VEGETARIANS
So for vegetarian it is recomended to consume commercially available fortified food with Vitamin B12
- Fortified oats
- Dairy products like
- Nutritional Yeast
- Fortified cereals
Its is strongly recomended for vegetarians that if they have developed deficiency then they should not depend only on dietary sources but also start Vitamin B12 suppliments either oral or injectable whatever recomended for each individual case.