Vitamin B12 deficiency has long been associated with vegan and vegetarian diets though there are a variety of causes. B12 is a nutrient produced by bacteria, and therefore the lack of absorption today may be partly attributed to better hygiene practices.
Importance of Vitamin B12
Vitamin B12 (also called cobalamin) helps maintain healthy nerve and red blood cells and is also needed to make DNA, which is why it's essential for pregnant and nursing women. Vitamin B12 is important to maintain a healthy nervous system, form healthy red blood cells, promote growth in children, improve memory and concentration and maintain energy levels. B12 also contains essential mineral elements and a long-term deficiency of it can even lead to brain damage. B12 has a very low recommended daily intake requirement, around 2-3 micrograms so a little planning can ensure that enough is consumed to prevent these health problems.
Symptoms of a B12 Deficiency
B12 is stored in the muscle tissue, liver and kidneys and up to seventy five percent is reabsorbed by the body. A deficiency could take from five to twenty years of inadequate intake to develop and typically manifests as nerve damage and pernicious anemia (a serious type of anemia where red blood cells are improperly formed and white blood cell count is low). Symptoms of vitamin B12 deficiency include fatigue, shortness of breath, nausea, menstrual problems, low sperm count, constipation and weight loss. If the deficiency lasts for a significant time is can affect the nervous system and cause problems such as muscle weakness, numbness, tingling in the fingers and toes, memory problems and depression.
Causes of B12 Deficiency
According to long-term vegan Pam Rotella most people with B12 deficiencies are not actually vegan. B12 deficiencies can occur due to the following factors:
- poor variety in diet and lack of consumption of foods containing B12
- smoking (the cyanide destroys B12)
- excessive alcohol consumption
- diarrhea
- parasites in body consuming B12
- poor absorption of B12 (possibly due to inadequate production of intrinsic factor).
How to Get Adequate B12
Recommendations for the intake of B12 vary considerably from country to country. The US recommended intake is 2.4 mcgs a day for adults rising to 2.8 mcgs for nursing mothers. Consuming enough B12 is easy and there are many methods of doing so. Absorption of B12 varies from about 50% for 1 mcg or less and about 0.5% for doses of 1000 mcgs. The least frequently B12 is taken, the higher the total amount needs to be to give the ideal absorbed amount.
Regular consumption of B12 fortified foods (one microgram of B12 three times a day with a few hours in between) is a good way to ensure an adequate intake. Alternatively taking a B12 supplement containing 10 mcgs or more daily can also provide the recommended daily intake. Any B12 supplement tablet should be allowed to dissolve in the mouth or chewed to aid absorption. Though there is a lack of evidence regarding B12 toxicity it is best not to take more than is required. Individuals with problems absorbing B12 may find taking 2000 mcg once a week works best as it does not rely on normal intrinsic factor in the gut. It is best to take any supplements under the advice of a medical professional.
Vegan Sources of Vitamin B12
Many foods that vegans include in their diet, such as soya milk, some breakfast cereals, dairy-free margarine and nutritional yeast are now fortified with vitamin B12. Seaweed, algae and fermented foods, like spirulina, miso and tempeh, may contain some vitamin B12 but are unreliable sources as they are not regarded as being sufficiently utilised by the body.
A B12 deficiency can have a serious impact on health and therefore all individuals whether vegan, vegetarian or meat-eater should ensure that they meet the recommended intake to be healthful and prevent the likelihood of serious health problems such as pernicious anemia. Read Cure Anemia by Increasing Iron Levels with Vegan Foods for more information.
Sources:
PamRotella.com Vegans and the B12 Deficiency Myth (Accessed August 15, 2010).
VeganHealth.com What Every Vegan Should Know about Vitamin B12 (Accessed August 15, 2010).
WebMD.com Vegetarian Diet and B12 Deficiency (Accessed August 15, 2010).
Disclaimer: The information contained in this article is for educational purposes only and should not be used for diagnosis or to guide treatment without the opinion of a health professional. Any reader who is concerned about his or her health should contact a doctor for advice.
Priya Chauhan - A designer, topic editor and feature writer (for Hinduism) and all round experimenter of healthy living; Priya enjoys being creative, and ...
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