Vitamin B12 (Methylcobalamin)
Vitamin B12 is an essential nutrient involved in red blood cell formation, nervous system function, DNA synthesis and energy metabolism. It is found naturally in animal-derived foods such as meat, fish, eggs and dairy.
Methylcobalamin is a biologically active form of vitamin B12 that can be used directly in important metabolic pathways, including methylation and homocysteine metabolism.
Red Blood Cells and Energy Metabolism
Vitamin B12 is required for the normal formation of red blood cells, which carry oxygen throughout the body.
It also works with folate in DNA synthesis and amino-acid metabolism. While B12 does not provide energy itself, inadequate levels can affect oxygen transport and normal cellular metabolism, which is why low B12 status is often associated with fatigue and weakness.
Brain and Nervous System Function
Vitamin B12 plays an important role in maintaining healthy nerve cells and the myelin sheath that helps protect nerve fibres.
It is also involved in pathways linked with neurotransmitter metabolism and normal cognitive function, making it especially relevant to brain health and healthy ageing.
Methylation and Homocysteine
Methylcobalamin works closely with L-5-methyltetrafolate (active folate) in the methylation cycle.
Together, they help convert homocysteine into methionine, which can then be used to produce compounds involved in DNA regulation, neurotransmitter synthesis and normal cellular maintenance.
This is why methylcobalamin and active folate are often included together in nutritional formulas.
Who May Need More Vitamin B12?
Vitamin B12 is naturally concentrated in animal foods, so people following vegan or highly plant-based diets may need fortified foods or supplementation.
Absorption can also decline with age, and some digestive conditions or medications can reduce the amount of B12 absorbed from food.
Vitamin B12 for Pets
Vitamin B12 is also important for dogs and cats, supporting red blood cell formation, nervous system function, digestion and normal energy metabolism.
Methylcobalamin may be included in pet formulas alongside active folate, DMG and other nutrients involved in methylation and cellular function, particularly in products aimed at brain health, healthy ageing and metabolic support.
Vitamin B12 in O2B Products
At O2B Healthy, vitamin B12 is included in O2B Vitamin B Complex, O2B Multi Vitamin and O2B MitoCell+. Our O2B K9+ MitoCell and O2B Feline+ MitoCell formulas also contain methylcobalamin, an active form of vitamin B12, while O2B Greenshell™ Mussel Powder naturally provides B12 as part of its marine nutrient profile. Across these products, vitamin B12 supports normal energy metabolism, red blood cell formation, nervous system function and healthy cellular processes.