Monday, October 11, 2010

Vitamin B12 and Your Health

Vitamin B12 is a water-soluble vitamin that is found exclusively in animal products. Consequently, vegans, who do not eat any animal products, may be at risk for vitamin B12 deficiency. A number of other health problems that interfere with vitamin B12 absorption can also lead to serious health problems.

Functions of Vitamin B12 
Vitamin B12 plays a critical role in the formation of hemoglobin, the oxygen-carrying portion of the red blood cells. It is necessary for proper nerve function. Another key role of vitamin B12 is in the synthesis of DNA. Additionally, vitamin B12 helps to limit the buildup of homocysteine, a compound that is associated with heart disease.

Vitamin B12 Deficiency: Causes 
Vitamin B12 deficiency may occur as a result of several conditions, including:
  1. Lack of an enzyme (intrinsic factor) that is necessary for the vitamin to be absorbed from the gut.
  2. Low dietary intake. Vegans, who do not eat any animal products may be at high risk for a B12 deficiency.
  3. Removal of certain parts of the small intestine or stomach, for example, in people who have undergone weight loss surgery or who required this type of surgery for other health conditions. Removal of parts of the stomach or small intestine could interfere with the ability to absorb the vitamin, thus resulting in a deficiency. 
  4. Other malabsorption problems.
Vitamin B12 Deficiency: Symptoms 
Symptoms of vitamin D12 include a type of anemia called pernicious anemia, tingling sensation or numbness in the arms and legs, fatigue, weakness, poor motor function and lack of balance. Other symptoms include memory loss, dementia, megaloblastic anemia, loss of appetite, and constipation.

Treatment of Vitamin B12 Deficiency
If low dietary intake is the main cause of a vitamin B12 deficiency (as is possible with vegans and raw food loyalists), this may be corrected by eating foods that have been fortified with the vitamin. However, if the problem is related to gut problems that interfere with your ability to absorb the vitamin, B12 shots are usually required.

Food Sources of Vitamin B12 
You can get vitamin B12 from meat, eggs, poultry, shellfish and milk. Vitamin Vitamin B12 is not found in plants. Therefore, if you are a vegetarian, you will need to get your vitamin B12 from foods that are enriched with the vitamin or take a B12 supplement. 

Vitamin B12 Requirement 
The RDA for vitamin B12 has been set at 0.9 to 1.8 micrograms for children 1 to 13 years of age, depending on age. For adolescents and adults the recommended intake is 2.4 micrograms. Lower amounts are required for infants while the requirements for pregnant and breastfeeding women are 2.6 and 2.8 micrograms, respectively.