### What you need to know
Vitamin B12 (cobalamin) is a water soluble vitamin required for several physiological processes, including normal nervous system functioning, and red blood cell development and maturation. It has antioxidant effects, is a co-factor in mitochondrial energy metabolism, and contributes to DNA synthesis, the methylation cycle, and epigenetic regulation.12 B12 is present in foods of animal origin, such as meat, eggs, and milk, or via food fortification. Healthy adults require an average intake of 4-7 mcg daily to maintain B12 status.34
Treatment with B12 may be required for a variety of reasons (table 1).
View this table:
Table 1
Main indications and administration routes for B12 treatment
Evidence from animal and human studies shows that B12 also has neuroprotective and anti-inflammatory properties,15 and intervention studies in humans have reported beneficial effects of better B12 status or B12 therapy in multiple sclerosis,16 Parkinson’s disease,17 mya