Vitamin B12, Cobalamin

Vitamin B12, or cobalamin, is a bright blue compound due to its high content of the mineral cobalt. It works with folic acid in many body processes, including the synthesis of DNA. Since vitamin B12 reactivates folic acid, a deficiency of vitamin B12 will result in a folic acid deficiency.

Vitamin B12 Deficiency

Vitamin B12 deficiency results in impaired nerve function, which can cause numbness, or burning feeling in the feet, as well as impaired mental function, which in the elderly can mimick Alzheimer's disease. In addition to depression or mental confusion, vitamin B12 deficiency can present as anemia; smooth, red tongue or diarrhea and is quite common in the elderly people. B12 deficiency is also reported to be a risk factor for heart disease, stroke and accelerated ageing.

Rich Sources of Vitamin B12

The richest sources of vitamin B12 are liver and kidney, followed by fish, eggs, meat and cheese. As for brewer's yeast and some cooked sea vegetables, there is some evidence that this form of B12 is not exactly the form that meets our bodily requirements, i.e. its bioavailability is much lower. The RDA for vitamin B12 is 2.0 milligrams. Vegetarians need to supplement their diets with vitamin B12.

What May Cause Vitamin B12 Deficiency?

Poor nutrition - People who get most of their calories from sugar and fat are at greater risk to develop B12 deficiency. Many adult Americans do not consume the RDA of 2.0 milligrams and are at greater risk of cobalamin deficiency-releated health problems.

Vitamin B12 Quick Calculator

So, what daily foods can supply the recommended daily allowance of vitamin B12 and give you that blissful peace of mind and a great feeling of being full of energy? Here is a selection of some foods that can be substituted for similar products in the same category:

  • Clams, steamed (20 small, app. 3 oz) - 4,450% of RDA
  • Atlantic mackerel, cooked (3 oz) - 808% of RDA
  • Chicken liver (3 oz) - 824% of RDA
  • Fresh tuna, cooked (3oz) - 463% of RDA
  • Salmon, canned, drained - 247% of RDA
  • Bluefish, uncooked (3 oz) - 229% of RDA

The highest amount of vitamin B12 among foods is 328 µg/100 g in salted and fermented salmon kidney that is called "Mefun". Eating only 0.8 g Mefun can supply the total RDA (2.4 µg/day) for an adult. It is popular only in Japan and may have the highest vitamin B12 content in nature. The vitamin B12 found in Mefun is not derived from vitamin B12–synthesizing bacteria, but is accumulated in the salmon kidney. The majority of vitamin B12 found in Mefun was recovered in the free vitamin B12 fractions. Mefun may be an excellent free vitamin B12 source for elderly people with food-bound vitamin B12 malabsorption.

Vitamin B12 in Children

Cobalamin deficiency in newborn children usually results from cobalamin deficiency in the mother. The affected children usually suffer from megaloblastic anaemia (a blood disorder characterised by red blood cells that are larger than normal, often with lower levels of white blood-cells and platelets - elements in the blood that assists in blood clotting); pancytopenia (shortage of all types of blood cells, including red and white blood cells as well as platelets) and neurological disorders if the diagnosis is delayed. Most cases of spina bifida and other neural tube defects result from maternal folate and/or cobalamin insufficiency in the periconceptual period. This deficiency is a rare condition in infants living in developed countries. It does occur, however, in infants who are breastfed by mothers with an inadequate diet. To prevent irreversible neurological damage, early recognition of any nutritional deficiencies is important.

Vegan diet in lactating women can cause vitamin B12 deficiency for their children with risk of an impaired neurological development that can result in cerebral atrophy (loss of brain cells). Vegan diet is a totally inadequate for pregnant and lactating women, especially for their children.

Obese children and adolescents are at greater risk of low vitamin B(12) concentration.

Vitamin B12 and Depression

Adequate nutrition is needed for many aspects of brain functioning. Poor diet quality, common in the United States, may be a risk factor for depression. Insufficient omega-3 fatty acid consumption increases the risk of depression. B12 supplementation usually results in dramatic improvement in mood.

Vitamin B12 and Diabetic Neuropathy

Vitamin B12 supplementation has been used with some success in treating diabetic neuropathy. Clinical studies show that combination therapy including methylcobalamin (active form of vitamin B12) can dramatically reduce pain. Methylcobalamin can halt degeneration of peripheral nerves, improve or eliminate painful sensations, and in some cases even restore sensation to limbs which have previously gone completely numb.

Vitamin B12 and Multiple Sclerosis

Multiple sclerosis (MS), an inflammatory disease of the central nervous system, commonly presents in young adults and affects twice as many women as men. Common symptoms include numbness, weakness, visual impairment, loss of balance, dizziness, urinary bladder urgency, fatigue, and depression. A B12 deficiency may aggravate the disease, accelerate its progress or impair recovery from MS. As B12 is an important factor in the formation of myelin (the white matter coating our nerves, enabling them to conduct impulses between the brain and other parts of the body) as well as in immune mechanisms, it has been suggested that there is a link between the disease and B12 deficiency.

Vitamin B-12 Toxicity In Cats