What to watch with Folsäure and longevity?

Folate (vitamin B9) is crucial for DNA synthesis and methylation, processes linked to biological aging. Some observational studies suggest that low folate levels are associated with increased cardiovascular mortality and cognitive decline. However, direct evidence that folate supplementation extends human lifespan is weak. Important caveats: high-dose folic acid can mask vitamin B12 deficiency, potentially leading to neurological damage. Additionally, excessive intake (e.g., >1 mg/day) may be associated with increased cancer risk in some studies. For longevity, maintaining an adequate but not excessive folate status (measured as RBC folate) appears more important than megadosing. A blood test (e.g., MyBody-X nutrient deficiency test) can assess current levels, but it is not a diagnostic tool. Evidence: human-moderate (observational studies, no longevity RCTs).