Vitamin B12 (Cobalamin)


Facts about Vitamin B12 (Cobalamin)

Vitamin B12 is a group of compounds also known as cobalamins. It occurs naturally in all foods of animal origin in form of methylcobalamin and 5-deoxyadenosylcobalamin. The synthetic forms of Vitamin B12 are Hydroxycobalamin and Cyanocobalamin. Our body needs to produce a specific protein called intrinsic factor to be able to absorb sufficient quantities of this nutrient.

Vitamin B12 is essential in cell, fat and carbohydrate metabolism, DNA and protein synthesis, and the activation of Vitamin B9. It is also necessary for normal blood formation, calcium absorption, and functioning of our nervous system. Vitamin B12 works closely with Vitamin B6 and B9.


Benefits of Vitamin B12 (Cobalamin)

Vitamin B12 helps to maintain a healthy nervous system, supports energy, and promotes growth. We need Vitamin B12 for normal blood formation. Vitamin B12 works closely with Vitamin B6 and B9 in regulating homocysteine levels among other functions.

Vitamin B1, B2, and B12 have pain-relieving properties that are even more effective when these Vitamins are used in combination.

Possible uses include:

  • AIDS/HIV support
  • age-related decline
  • allergies
  • Alzheimer's disease
  • asthma
  • atherosclerosis
  • dermatitis
  • cardiac events
  • chronic fatigue syndrome
  • Crohn's disease
  • cystic fibrosis
  • depression
  • diabetes mellitus
  • down's syndrome
  • hepatitis
  • herpes zoster
  • hives
  • insomnia
  • low back pain
  • male infertility
  • Multiple Sclerosis
  • neural tube defects (risk reduction)
  • osteoarthritis
  • osteoporosis
  • pain
  • pernicious anaemia
  • restless leg syndrome
  • schizophrenia
  • tinnitus

Vitamin B12 (Cobalamin) Deficiency

A Vitamin B12 deficiency affects growth, function, and repair of all cells and tissues. It can be difficult to recognize because many of its symptoms are general and can also result from a variety of medical conditions. Furthermore, high intakes of Vitamin B9 can cover-up a B12 deficiency without correcting the neurological damage that also occurs.

Inadequate intake, food malabsorption, and interaction with certain medication are considered the most common reasons for a deficiency. Heavy smoking and alcohol use further reduce absorption of Vitamin B12. Vegetarians might be at an increased risk because this nutrient occurs almost exclusively in foods of animal origin. It also appears that Vitamin B12 absorption declines with age.

Deficiency symptoms include:

  • agitation
  • bone loss
  • confusion
  • depression
  • easy bruising
  • constipation
  • dermatitis
  • fatigue
  • loss of appetite
  • nausea
  • nervousness
  • neurological changes
  • pernicious anaemia
  • poor blood clotting
  • poor memory
  • shortness of breath
  • skin sensitivity
  • vomiting
  • weakness

Vitamin B12 (Cobalamin) Toxicity

Vitamin B12 has no known toxicity from excess intakes of food and supplements. However, a few adverse effects and possible dangers may exist from intravenous megadoses. Furthermore, large doses of Vitamin B12 and Vitamin B9 might stimulate tumour growth!

Adverse Effects may include:

  • acne
  • diarrhoea
  • hives
  • itchy skin
  • peripheral vascular thrombosis

Foods high in Vitamin B12 (Cobalamin)

Vitamin B12 occurs naturally almost exclusively in foods of animal origin. However, there are a few foods of vegetable origin, such as seaweed and microalgae, which provide small amounts of B12.

Vitamin B12 is light sensitive and can easily be destroyed by cooking.

Dietary sources include:

  • cheese
  • dairy products
  • eggs
  • liver
  • meat
  • milk
  • organ meats
  • oysters
  • salt-water fish

The Dietary Reference Intakes (DRIs) for Vitamin B12, developed by the Food and Nutrition Board (FNB) at the Institute of Medicine of The National Academies, currently state 2.4mcg for adult men and women. For people older than 50 years it is recommended they meet their DRI's from foods fortified with B12 or supplements containing B12 for better bioavailability. No Tolerable Upper Intake Levels have been established. Australia and New Zealand adapted the same values as their Nutrient Reference Values (NRVs).


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