About Vitamin B12
Vitamin B12, also known as cobalamin, is a water-soluble vitamin that plays crucial roles in red blood cell formation, neurological function, and DNA synthesis. It's one of the most complex vitamins with a unique molecular structure containing cobalt.
The Most Complex Vitamin
B12 has the largest and most complex molecular structure of all vitamins, containing the metal cobalt.
Key Facts About B12
Essential for Life
B12 is crucial for DNA synthesis, red blood cell formation, and neurological function
Only from Animal Sources
Found almost exclusively in meat, fish, eggs, and dairy products
Complex Absorption
Requires intrinsic factor from stomach cells for proper absorption
Long-term Storage
Liver can store several years' worth, making deficiency slow to develop
What is Vitamin B12?
Vitamin B12 is essential for normal brain and nervous system function, red blood cell formation, and the synthesis of DNA. Unlike other vitamins, B12 contains a metal element (cobalt) and has the largest and most complex chemical structure of all vitamins.
Why Do We Need B12?
B12 is required for proper red blood cell formation, neurological function, and DNA synthesis. It works closely with folate in many body processes, including the synthesis of DNA, red blood cells, and myelin that surrounds nerve fibres.
How Much B12 Do We Need?
Adults need approximately 2.4 micrograms of B12 daily. Pregnant and breastfeeding women require slightly more. The body can store several years' worth of B12 in the liver, which is why deficiency can take years to develop.
Food Sources of B12
B12 is naturally found almost exclusively in animal products including meat, fish, eggs, and dairy. Some fortified foods like nutritional yeast and plant-based milks also provide B12. This makes vegetarians and vegans particularly at risk of deficiency.
Different Forms of B12
B12 exists in several different forms, each with specific uses and benefits
Cyanocobalamin
Supplements & Fortified FoodsMost common synthetic form used in supplements and fortified foods
Hydroxocobalamin
Injections & TreatmentNatural form used in B12 injections, longer-lasting in the body
Methylcobalamin
Neurological SupportActive form that crosses the blood-brain barrier easily
Adenosylcobalamin
Cellular EnergyActive form important for energy metabolism in cells
Learn More About B12 Deficiency
Understanding B12 is the first step to recognising deficiency. Explore our comprehensive resources to learn about causes, symptoms, and treatment options.