Vitamin B12 – a vital nutrient for our brains, nerves and red blood cells – is lacking in vegan and vegetarian diets and hard to absorb for people with stomach and digestive problems. No wonder it’s such a popular supplement! But not all B12 supplements are equal. We blow the lid on the cheaper, synthetic B12 supplements that aren’t biologically active.
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The purpose and benefits of vitamin B12
Vitamin B12, also known as cobalamin, plays a crucial role in various bodily functions. Overall, vitamin B12 is vital for maintaining energy levels, keeping the nervous system healthy, forming new red blood cells, supporting cognitive function, and promoting overall health and well-being.
Active forms of vitamin B12 participate in metabolic processes that convert food into energy, aiding in the breakdown of fats and proteins. this is why vitamin B12 supplements are popular to give a sudden and powerful energy boost.
Additionally, vitamin B12 supports the synthesis of DNA and RNA, which is essential for cell growth and repair. This means you cannot regenerate or maintain any part of the body without enough B12.
In the nervous system, vitamin B12 contributes to the production of myelin, a protective sheath that surrounds nerve fibres and facilitates efficient nerve signalling. This is why a B12 deficiency can cause tingling, numbness or even more severe symptoms. This vitamin also helps maintain the integrity of the brain and spinal cord, which is a mass of nerves. A B12 deficiency also causes damage to the brain, and severe deficiency disease resembles brain damage and mental illness.
Furthermore, vitamin B12 is involved in the formation of red blood cells in bone marrow, ensuring adequate oxygen transport throughout the body. Without enough vitamin B12, our red blood cells become abnormally large (blood cells like this are called “megaloblasts”) and they are inefficient at carrying oxygen, so this condition is called megaloblastic anaemia.
Who needs more vitamin B12?
People who take certain medicines are at risk of a B12 deficiency. These include
- proton pump inhibitors (PPIs)
- metformin
- nitrous oxide
An autoimmune disease called pernicious anaemia causes vitamin B12 deficiency because the body cannot absorb it.
Vegetarians and vegans are at risk because plant-based diets contain very little vitamin B12 indeed.
Some people don’t absorb B12 well. These include older adults, as well as people with gastrointestinal conditions including celiac disease and Crohn’s disease. People who have had weight loss surgery such as gastric bands also fall into this category.
Pregnant and breastfeeding women may need more vitamin B12 than average and are at risk of deficiency.
The Four forms of vitamin B12
Cobalamin, commonly known as vitamin B12, exists in several forms, each with distinct chemical structures and physiological roles in the body. The four primary forms of cobalamin are cyanocobalamin, hydroxocobalamin, methylcobalamin, and adenosylcobalamin.
Depending on individual needs and health considerations, different forms of vitamin B12 may be preferred for supplementation or treatment.
Cyanocobalamin
Best suited for: B12 fortified foods.
Cyanocobalamin is the synthetic form of vitamin B12. It consists of a cobalt ion bonded to a cyanide molecule – yes, cyanide! Once you eat it, cyanocobalamin needs to be changed by the body. It goes through metabolic conversion in the body to produce active forms of vitamin B12, namely methylcobalamin and adenosylcobalamin.
Pros of cyanocobalamin
It’s commonly added to fortified foods because it’s more stable with a long shelf life, so it’s a convenient form to use in things like breakfast cereals. It’s also used in the cheapest B12 supplements because it’s economical to make.
Cons of cyanocobalamin
It’s artificial, and not ready for our bodies to use. Our bodies have to convert cyanocobalamin into the active forms of B12 (methylcobalamin and adenosylcobalamin) through metabolic processes, which are less efficient than other forms.
Hydroxocobalamin
Best suited for: Injectable B12 formulations for treating medical conditions.
Hydroxocobalamin is a naturally occurring form of vitamin B12 found in various foods. It contains a hydroxyl group attached to the cobalt ion.
Pros of hydroxocobalamin
Hydroxocobalamin has a longer half-life compared to other forms, which means it stays in the body longer. It can be stored in the body for up to 45 days, making it suitable for treating people with pernicious anaemia, an autoimmune disease which means they cannot absorb vitamin B12 from food. They have a monthly injection which has to keep their body supplied until the next injection.
Cons of hydroxocobalamin
Our bodies have to put hydroxocobalamin from foods or injections through a series of chemical reactions to turn it into the biologically active forms of B12. Depending on genetics, some people are less efficient at these processes and this can create a metabolic bottleneck.
Methylcobalamin
Best suited for: Neurological health, methylation support, genetic variants affecting B12 metabolism.
Methylcobalamin is the biologically active form of vitamin B12 found in our bodies, once they have prepared it ready to use. It contains a methyl group (-CH3) attached to the cobalt ion, preparing it for involvement in processes such as making DNA for new body cells, producing neurotransmitters, and metabolising harmful to help keep the health heart and arteries healthy. It plays a crucial role in methylation reactions within the body. It readily crosses the blood-brain barrier and participates in processes such as DNA synthesis, neurotransmitter production, and homocysteine metabolism.
Pros of methylcobalamin
Methylcobalamin is easily absorbed in supplement form and used by cells. It’s considered ideal for people with neurological symptoms, mood disorders, or conditions related to impaired methylation, such as certain genetic polymorphisms or methylation pathway deficiencies.
Adenosylcobalamin
Best suited for: Energy metabolism, mitochondrial support, fatigue management.
Adenosylcobalamin, also known as dibencozide, is another active form of vitamin B12 involved in cellular energy metabolism. It contains an adenosine nucleotide attached to the cobalt ion and serves as a cofactor for enzymes involved in the breakdown of fatty acids and amino acids for energy production. Adenosylcobalamin primarily functions within the mitochondria, the energy-producing organelles of cells. It is the active coenzyme form of B12 involved in cellular energy production and mitochondrial function. It additionally serves as a cofactor for enzymes responsible for the breakdown of fatty acids and amino acids within mitochondria.
Pros of adenosylcobalamin
Adenosylcobalamin is easily used by the body and may be beneficial for people who need to support mitochondrial function and energy levels. It enhances energy metabolism, and can relieve symptoms of fatigue or low energy levels.
Conclusion: A dirty little supplement secret?
Most big supplement brands sell cyanocobalamin or hydroxycobalamin. There’s nothing really wrong with them, they are vitamin B12 after all.
But the downside is that they’re not ready for your body to use. Depending on your genetics, you may have limitations on how much of them your body can activate and use. Your levels of many other nutrients is also going to stop you converting these cheaper supplements into forms of B12 that your body can use.
It’s clear that, if you want to feel the full benefits of a high-strength vitamin B12 supplement, it needs to deliver both body-ready forms of vitamin B12.
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Vitamin B12
- Dual active formula with methyl B12 + adenosyl B12
- Made in the UK
- Easy to swallow tiny tablets
VitaBright provides a dual-active Vitamin B12 supplement, blending the bio-active forms adenosylcobalamin and methylcobalamin in a 50-50 mix. As we learned above, adenosylcobalamin and methylcobalamin often work together to increase adequate intake.
Vitamin B12 FAQs
What is vitamin B12, and why is it important?
Vitamin B12, also known as cobalamin, is a water-soluble vitamin essential for various physiological processes in the body, including DNA synthesis, red blood cell formation, neurological function, and energy metabolism. It plays a crucial role in maintaining nerve health, supporting brain function, and contributing to overall well-being.
What are the main sources of vitamin B12?
Vitamin B12 is primarily found in animal-derived foods such as meat, fish, poultry, eggs, and dairy products. Plant-based sources like fortified foods and supplements can also provide vitamin B12, although they may be less bioavailable for some individuals, particularly vegans and vegetarians.
What are the symptoms of vitamin B12 deficiency?
Vitamin B12 deficiency can lead to various symptoms and health complications, including fatigue, weakness, pale or jaundiced skin, tingling or numbness in the hands and feet, difficulty walking, memory problems, cognitive impairment, mood changes, and megaloblastic anaemia (also called pernicious anaemia). Severe or prolonged deficiency may result in neurological disorders such as peripheral neuropathy or even irreversible nerve damage.
Who is at risk of vitamin B12 deficiency?
People at risk of vitamin B12 deficiency include vegetarians, vegans, and older adults. Also at risk are people with gastrointestinal disorders including pernicious anaemia, celiac disease and Crohn’s disease. Furthermore, people who have had weight loss surgery such as gastric bands, pregnant and breastfeeding women, and anyone with certain genetic factors affecting B12 absorption or metabolism may develop a vitamin B12 deficiency.
How is vitamin B12 deficiency diagnosed?
Vitamin B12 deficiency is typically diagnosed through blood tests measuring serum B12 levels, along with additional markers such as methylmalonic acid (MMA) and homocysteine levels to assess functional deficiencies. Clinical evaluation of symptoms, medical history, and risk factors may also be considered in the diagnostic process.
Can vitamin B12 deficiency be treated?
Yes, vitamin B12 deficiency can be treated effectively with oral or injectable B12 supplements, depending on the cause of the deficiency. Oral supplements of methylcobalamin or adenosylcobalamin is are ideal for people with most milder levels of vitamin B12 deficiency.
People with pernicious anaemia, an autoimmune disease which means they cannot absorb vitamin B12 via the stomach need injections of hydroxocobalamin or cyanocobalamin instead. Injections may also be used for severe deficiency cases caused by celiac disease of Crohn’s disease or too little or too much stomach acid.
Are there any side effects or risks associated with vitamin B12 supplementation?
Vitamin B12 supplementation is generally safe and well-tolerated when taken within recommended doses. Rare side effects may include mild gastrointestinal disturbances (e.g., nausea, diarrhea) or allergic reactions. High-dose B12 supplementation should be avoided in individuals with certain medical conditions, such as Leber’s disease or kidney disease, without medical supervision.
Can vitamin B12 improve energy levels or cognitive function?
Adequate vitamin B12 levels are essential for maintaining energy metabolism, neurological health, and cognitive function. Supplementing with vitamin B12 may help alleviate fatigue, improve mental clarity, and support overall vitality, especially in individuals with B12 deficiency or suboptimal levels. However, vitamin B12 supplementation may not necessarily enhance energy or cognitive function in individuals with adequate B12 status.
How does vitamin B12 increase energy?
Vitamin B12 helps convert food into glucose, which is the sugar carried in the blood and used as fuel by cells to produce energy. Additionally, B12 helps grow new red blood cells, which carry oxygen to tissues and organs, further supporting energy production.
Why do vegans need vitamin B12?
Vitamin B12 is only found in foods derived from animals, mostly meat and dairy products. A plant-based diet can’t provide the body with this supplement.
How is vitamin B12 absorbed?
The digestion and absorption process begins with vitamin B12 from food binding to a protein called ‘intrinsic factor’ in the stomach. Then, in the small intestine, B12 is absorbed into the bloodstream and transported to cells and tissues where it’s needed.
