Vitamin B12 is an essential water-soluble vitamin belonging to the family of eight B vitamins. It plays many important roles in the body, such as creating energy and maintaining healthy tissues. This vitamin can be obtained through a well-balanced diet; however, insufficient dietary intake of vitamin B12 may lead to vitamin B12 deficiency and anemia.
Health benefits of vitamin B12
• DNA synthesis
• Heart and blood function
• Megaloblastic anemia prevention (a condition characterized by enlarged red blood cells due to
vitamin B12 deficiency)
• Neuroprotection and nerve function
• Pain reduction
Forms of vitamin B12
Form of B12: Adenosylcobalamin
Function: Energy and muscle function
Source: Meat
Form of B12: Cyanocobalamin
Function: Synthetic B12
Source: Most supplements
Form of B12: Hydroxocobalamin
Function: Long-lasting B12; detoxification
Source: Meat
Form of B12: Methylcobalamin
Function: DNA and nerve function
Source: Dairy
Recommended daily intake of vitamin B12
The following timeline provides the daily Recommended Dietary Allowance (RDA) and Adequate Intake (AI) of vitamin B12 for various populations.
Dietary sources of vitamin B12
The quantities of vitamin B12 provided below are based on typical serving sizes of each source. Quantities may vary depending on brand and preparation methods. Out of four forms of B12, the three found naturally in the diet are methylcobalamin, hydroxocobalamin, and adenosylcobalamin.
