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Sirtuin-1 (SIRT1) is an NAD+-dependent deacetylase known as a master regulator of metabolic health, mitochondrial biogenesis, and cellular longevity pathways

[16] Although cyanocobalamin lacks a defined upper-toxicity threshold due to its water solubility and renal elimination, exceptionally high cumulative doses have been temporally associated with acneiform eruptions, altered potassium homeostasis, and theoretical thrombotic risk, emphasizing the importance of evidence-based dosing

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The compound remains in a regulatory gray area: recognized as safe, but without the efficacy data needed for pharmaceutical approval