Vitamin B12

Vitamin B12 plays an important role in red blood cell production, proper development of nerve cells and in the metabolism of macronutrients such as protein, carbohydrates and fat.

B12 Food Sources

Vitamin B12 is a controversial vitamin, especially among vegetarian and vegan circles. While most people obtain the vitamin through animal foods (meat, shellfish, milk and eggs), plant sources are few and are not reliable sources of this vitamin. Some nutrition experts suggest that vitamin B12 may not be needed on a daily basis because humans can store it in the body for up to 20 years or more. However, studies of long-term vegans who do not take vitamin B12 supplements have consistently shown deficiency in this vitamin.

Nutritional and Brewers yeast are significant sources of vitamin B12 for vegans, as are supplements and fortified foods such as cereals. Tofus, fermented soy products, sea vegetables (sea weed), barley grass, unwashed organic produce and human gut bacteria vary in their potential for vitamin B12 availability and are not generally regarded as reliable sources.

B12 Deficiency

A variety of symptoms may result from vitamin B12 deficiency including anemia, nervousness, depression, heart palpitations, memory problems, weakness, tingling and numbness in the feet, decrease reflexes, difficulty swallowing, decreased blood clotting, fatigue, paleness, weak pulse and red, sore tongue. Prolonged deficiency can lead to irreversible neurological damage.

Vitamin B12 requires adequate levels of vitamin B6 for proper absorption. Vitamin E is required to convert B12 from it’s inactive form to it’s active form. A lack of vitamin E in the diet can also contribute to a deficiency in B12.

B12 Toxicity

There are no documented cases of toxicity from vitamin B12. In fact, it is virtually impossible to overdose from dietary sources of B12.

The Effects of Cooking On B12

The effects of cooking, processing and storing on vitamin B12 varies and cooking may reduce the availability of the vitamin up to 50%.

For more on vitamin B12 and the vegan diet, click here.

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