What role does B12 play in longevity?

Vitamin B12 is crucial for DNA synthesis, red blood cell formation, and neurological function. It plays a key role in homocysteine metabolism, and elevated homocysteine is linked to cardiovascular disease and cognitive decline—both factors in aging. However, direct evidence that B12 supplementation extends lifespan is limited. Most support comes from observational studies, not robust clinical trials. While deficiency is common in older adults, supplementation in those with normal levels shows no clear longevity benefit. The MyBody-X context does not directly address B12 and longevity. Thus, while maintaining adequate B12 is important for health, it is not a proven anti-aging intervention. Evidence is moderate, based on mechanistic plausibility and observational data, but not strong enough for definitive anti-aging claims.