Important Facts about Vitamin B12
Sally Feltner MS, PhD Diet and Health, General October 15, 2020 2 Minutes
March 27, 2019 by foodworksblog Leave a comment
Vitamin B12 is often overlooked as to its importance to human health. Vitamin B12 is needed for the metabolism of another vitamin, folate as well as fatty acids to maintain the insulating layer of myelin surrounding nerve fibers. When myelin degenerates, neurological symptoms occur that include numbness, tingling, memory loss and disorientation. If not treated, it can eventually cause paralysis and death. On the other hand, a deficiency is rare, but can be a public health concern due to marginal B12 status due to either low intake or problems with absorption as often found in the older adult. This deficiency may also occur in people who attempt to practice a strict vegan diet as this vitamin is found almost exclusively in animal products.Vegan diets are a concern due to B12 found only in animal foods. Severe deficiencies have been found in breast – fed infants of vegan women and marginal deficiencies for all vegans if supplemental or fortified foods are not consumed in the diet.
The absorption of B12 from food requires adequate levels of stomach acid, intrinsic factor (produced in the stomach) and pancreatic secretions. Even though it is a water-soluble vitamin, the body stores and reuses it more efficiently that it does other water soluble vitamins. Poor absorption of vitamin B12 can result from a condition called pernicious anemia. It is an autoimmune disease in which the cells in the stomach that produce intrinsic factor are destroyed. This can be treated by using injections or megadoses of the vitamin. When this occurs, intrinsic factor is not necessary since synthetic B12 found in supplements are used that bypass the digestive system.
Primary Food Sources
Milk and cheese
Ready to eat cereals
Highlights and Comments
Older people, those with previous stomach surgery, and vegans are at risk for deficiency.
Some people become B12 deficient because they are unable to absorb it (pernicious anemia).
Vitamin B12 is found in animal products and microorganisms only.
Source: Smolin, Lori A. & , Grosvenor, Mary B. Nutrition, Science and Applications, Third Edition
Judith E. Brown, Nutrition Now, 7th Edition