Vitamin B12 is a soluble vitamin, also known as cobalamin. This vitamin plays a key role in the production of DNA in the cells and is also active in the production of red blood cells.
The main source of B12 is are animal-based foods such as meat, poultry, fish, eggs, milk products and sea food. Additionally, there are a number of products that are enriched with vitamin B12 - cereals, soy products and certain snacks. B12 found in food is connected to various proteins and in order to be absorbed into the intestine, it needs to undergo a number of processes. The body's absorption of vitamin B12 is dependent on a number of factors in the digestive system. The absorption process is complex.
An average diet contains 5-7 mg of B12 a day, where the daily recommended dose is 6-9 mg. The body stores most of the B12 in the liver, therefore a B12 deficiency only develops after years of a vitamin B12 deficient diet. Only 2% of B12 deficiencies are a result of diets - most cases develop when there is a problem with the absorption of B12 into the body. Causes for deficiency include alcoholism, chronic stomach infections, chronic acid reflux medication, Crohn's diseases, bowel resectioning and more. There has been a rising trend of B12 deficiency among the elderly - 30% of people over the age of 70 suffer from a vitamin B12 deficiency.
B12 and Vegetarians
Vegetarians who eat animal by products can get the daily recommended amount of B12, as long as they maintain a balanced vegetarian diet. Vegans are at a risk of developing a vitamin B12 deficiency, although this deficiency does take a number of years to develop. Vegans are recommended to take vitamin B12 supplements.
Pregnant, nursing or teenage vegetarians are at a higher risk of developing a deficiency. A B12 deficiency during pregnancy can result in the fetus developing birth defects. Growing teenagers require a higher amount of vitamin B12.