# NADH

NADH is the reduced form of NAD+, generated when NAD+ accepts electrons during glycolysis, the citric acid cycle, and fatty acid oxidation. It delivers electrons to the mitochondrial electron transport chain, driving ATP synthesis. The cellular NAD+/NADH ratio reflects metabolic state and influences sirtuin activity, redox signaling, and substrate selection. A shifted ratio toward NADH, often observed in aging and metabolic disease, is associated with reductive stress and mitochondrial dysfunction.

## Sources

- Hirst J. (2013). Mitochondrial complex I. Annual Review of Biochemistry. https://doi.org/10.1146/annurev-biochem-070511-103700
- Covarrubias AJ, Perrone R, Grozio A, Verdin E. (2021). NAD+ metabolism and its roles in cellular processes during ageing. Nature Reviews Molecular Cell Biology. https://doi.org/10.1038/s41580-020-00313-x

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_Canonical: https://longevity-germany.com/en/glossary/nadh · Part of Longevity Cities · Updated 2026-05-02_