What is the role of vitamin B12 (cobalamin) in my body?

You need vitamin B12, also known as cobalamin, to make red blood cells, which carry oxygen in the blood. The nutrient is also essential to the normal health, development and functioning of your brain, nerves and other body parts. Vitamin B12 is also needed to make DNA, your cells' genetic "blueprint."  

You can get vitamin B12 by eating foods including fish, meat, poultry, eggs, dairy products and some fortified breakfast cereals. If you can't get enough vitamin B12 in your diet or you have a condition that makes it difficult for you to absorb vitamin B12 normally, your doctor may recommend taking supplements. Talk to your doctor for more information.
The last of the B vitamins to be discovered, vitamin B12 has two main roles: protein synthesis and energy production from fats and  proteins. Vitamin B12 is only available from animal sources, which is why vegetarians often rely on fortified cereals to meet their nutrient needs. The earliest sign of B12 deficiency is anemia. Over a longer duration, B12 deficiency leads to nerve damage that starts with tingling and numbness and can progress to difficulty walking and mental disorders. As we get older we make less stomach acid, which is needed to absorb B12. The elderly and those taking drugs that lower stomach acid should take extra precautions to get enough vitamin B12.

Heart Health

One of vitamin B12’s metabolic functions is to help convert homocysteine, an amino acid that in excess ups the risk for cardiovascular disease, to a useful amino acid needed for protein synthesis. Although vitamin B12 (as well as vitamin B6 and folate) supplementation can effectively reduce homocysteine levels, so far taking it in supplement form has not been found to curb cardiovascular disease.

Brain Health

A French review of studies on diet and dementia highlights the fact that Alzheimer’s sufferers almost always have low vitamin B12 levels. In a Swedish study, 370 subjects with low serum levels of B12 actually doubled their risk of developing Alzheimer’s. And a study at the University of Oxford in England demonstrated that people with below-average B12 levels were six times more likely to experience “brain shrinkage.” While the precise mechanism of this effect is not thoroughly understood, researchers believe that low levels of B12 may inhibit proper DNA repair, which over time can lead to memory loss.

Bone Health

Vitamin B12 deficiency has also been shown to increase the risk for bone fractures. Tufts University researchers found that men and women with low-plasma vitamin B12 levels had lower bone-mineral density at the hip and spine, respectively. The link was still significant even after adjusting for homocysteine (a risk factor for bone fracture), which suggests that modifying vitamin B12 levels could help prevent osteoporosis.

Mood Boost

University of North Carolina researchers showed that 30 percent of patients who were hospitalized for depression had low levels of vitamin B12. Researchers speculate that this vitamin may help synthesize serotonin, one of the feel-good neurotransmitters in the brain.
Michael T. Murray, ND
Naturopathic Medicine

Vitamin B12, or cobalamin, was isolated from liver extract in 1948 and identified as the nutritional factor in liver that prevented pernicious anemia. The crystallized compound of vitamin B12 is bright blue due to its high content of the mineral cobalt. Vitamin B12 works with folic acid in many body processes, including the synthesis of DNA. Since Vitamin B12 reactivates folic acid, a deficiency of B12 will result in a folic acid deficiency if folic acid levels are only marginal.

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Encyclopedia of Healing Foods

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.