Vitamin B12 Information

Vitamin B12 belongs to the vitamin B complex group and is used for the treatment of pernicious anemia. It is also referred to as cobalamin since it contains cobalt. Primarily, vitamin B12 is found in protein rich foods like meat, particularly shellfish and liver, dairy products, and eggs. In fact, it is bound to the protein in such food, and once consumed is released by the hydrochloric acid secreted in the stomach as part of the digestive process. Once it is released, it combines with a substance produced by the mucosa of the stomach known as intrinsic factor, or IF, after which the body is able to absorb it from the intestinal tract. Pernicious anemia due to vitamin B12 deficiency is often caused as a result of a lack of intrinsic factor.

Vitamin B12 Information – Plant Sources

Considerable amount of research has been done on whether vitamin B12 can be availed of from plant sources such as algae like spirulina, seaweeds, and soy products, which were thought to be high in B12. However, when soy products like miso, tempeh, tamari, and shoyu were analyzed, it was found that they did not have significant amounts of vitamin B12. And although nori, which is a seaweed, and spirulina have both been found to contain fair amounts of the vitamin, it is however thought that the B12 they have are compounds that are structurally similar to vitamin B12, and are referred to as B12 analogues, which cannot be utilized by the body to satisfy dietary requirements. As a matter of fact, research indicates that the so-called vitamin B12 supplements like spirulina may actually increase the risk of deficiency of the vitamin since the B12 analogues may compete with other sources of vitamin B12, and thereby impede its metabolism. Therefore, according to current consensus amongst nutritionists, it is agreed that no plants can be regarded as a good source of vitamin B12.

This can prove to be problematic for people on strict vegetarian diets, such as vegans, who may not be consuming enough dietary sources of vitamin B12, while their vegetarian sources have been proven to be ineffective, and may even exacerbate the deficiency of the vitamin.

Vitamin B12 Information – Functions

Vitamin B12 is water soluble, like all the other vitamins belonging to the B-complex group. Some of its main functions are: Maintaining the nervous system; and Helping in the formation of red blood cells.

Vitamin B12 and the Nervous System: Vitamin B12 is vital for the maintenance of the nervous system at its optimum. An insulating fatty covering that is made up of a complex protein, known as myelin, is what nerves are surrounded by. This myelin is maintained at its optimum best by vitamin B12 since it metabolizes the fatty acids essential for its maintenance. Therefore, if there is a deficiency of vitamin B12 for a prolonged period, it can result in the degeneration of nerves and irreversible damage to the neurological system.

Vitamin B12 and the Formation of Red Blood Cells: Vitamin B12 is also an essential factor for DNA to be synthesized rapidly during the process of cell division. This particularly imperative in those tissues where cells divide rapidly, such as bone marrow tissues where there is formation of red blood cells. When there is a deficiency of vitamin B12, it results in a disruption of DNA production, which in turn causes abnormal cells to occur, which are known as megaloblasts. This causes anemia, which in turn causes pallor, excessive fatigue, listlessness, breathlessness, and susceptibility to infection. Some of the other effects of anemia are menstrual disorders and a sore and smooth tongue.

When combined with vitamin B6 and folic acid, vitamin B12 also helps in controlling homocysteine levels. When the homocysteine levels are high it increases the risk of conditions like Alzheimer’s disease, osteoporosis, coronary heart disease, and stroke.

Vitamin B12 Information – Required Intake

The term Reference Nutrient Intake, or RNI, has now replaced what used to be previously known as Recommended Daily Amounts, or RDA. The RNI refers to the amount of the nutrient that is sufficient for at least 97 percent of the population. Therefore, the RNI for vitamin B12, which is demarcated as µg per day, wherein 1 mg = 1000 µg, according to various ages are: 0.3 µg for 0 – 6 months; 0.4 µg for 7 – 12 months; 0.5 µg for 1 – 3 years; 0.8 µg for 4 – 6 years; 1.0 µg for 7 – 10 years; 1.2 µg for 11 – 14 years; 1.5 µg for 15 years and above; and 2.0 µg for women breast feeding their infants.

It is thought that pregnant women do not require any extra amounts of vitamin B12, although not much information about this is actually known. Women breast-feeding their children need extra amounts of B12 so that there is enough of it in their breast milk.

Being very low in toxicity, taking high amounts of vitamin B12 is not thought to be harmful.

Free-range eggs and dairy products are some of the best sources of vitamin B12 for vegetarians. For example, a boiled egg has 0.7 µg, a 40-gram slice of vegetarian cheese has 0.5 µg, and half a pint of milk has 1.2 µg. However, vitamin B12 can be destroyed when milk is boiled, and the fermentation process when yogurt is manufactured also destroys it.

As for vegans, it is recommended that they include vitamin B12 fortified foods in their diet, such as breakfast cereals, sunflower and vegetable margarines, soya milk, textured vegetable protein, veggieburger mixes, yeast extracts, and so on.