Vitamin B12 an important water-soluble vitamin is required for maintaining healthy nerve cells and red blood cells. Vitamin B12 is also needed to produce DNA, the generic material found in all cells. Vitamin B12 is attached to the protein in foods, and is released by the action of hydrochloric acid in the stomach during the process of digestion. When it is released vitamin B12 then mixes with a substance known as the intrinsic factor which is absorbed in the small intestine.

Sources of Vitamin B12

Vitamin B12 is found in animal derived food products which include fish, meat, poultry, milk and milk products (Office of Dietary Supplements). Vegetarians, especially vegan vegetarians can get vitamin B12 from other sources such as fortified cereals, fortified soy milk, almond milk and other milk substitutes.

Recommended Dietary Allowances of B12 (Office of Dietary Supplements)

Males and females between the ages of 1 - 3 years require 0.9 μg/day; 1.2 μg/day between the ages of 4 - 8 years; 1.8 μg/day between the ages of 9 - 13; 2.4 μg/day between the ages 14 - 18 years (if pregnant 2.6 μg/day, and if breastfeeding 2.8 μg/day); for 19 years and older the requirement is 2.4 μg/day (if pregnant 2.6 μg/day and if breastfeeding 2.8 μg/day).

The actual requirements of vitamin B12 is small, yet is often sold as 500 microgram (mcg) or 1000 mcg tablets. The body does not store the surplus! Vitamin B12 is best taken (chewed or absorbed under the tongue) with a meal. Women who are vegan vegetarians and are pregnant or breastfeeding must make sure that they are getting adequate amounts of vitamin B12 to meet their own needs in addition to those of the fetus or newborn. Vitmain B12 needs should be discussed with your healthcare provider. Food sources are usually more readily absorbed than compounds.

Conditions Associated with Vitamin B12 Deficiency

One of the factors that contribute to vitamin B12 deficiency in individuals 50 years and older is the decreased production of hydrochloric acid in the stomach which is often manifested as meal related burping, bloating, and flatulence together with other symptoms.

Among the most common signs and symptoms associated with vitamin B12 deficiency are: fatigue, weakness, constipation, anemia and loss of appetite. Low vitamin B12 blood levels have also been reported in women with breast cancer when compared to women without breast cancer.

Neurological complaints such as tingling, numbness and pins and needles in hands and feet may also be experienced by individuals with vitamin B12 deficiency. Other symptoms include memory loss, disorientation, depression, dementia (some patients diagnosed with Alzheimer's disease have very low vitamin B12 blood levels), sore mouth or tongue.

Vitamin B12 deficiency in infants may be manifested as failure to thrive, delayed development, seizures, and lethargy.

Vitamin B12 deficiency can be diagnosed by means of blood tests. Please consult with a health care provider if you have any concerns about your vitamin B12 status.