# Circadian rhythm

Your circadian rhythm is the body's roughly 24-hour internal clock. It coordinates when you sleep and wake, when hormones release, and your body temperature and metabolism. It is run by the suprachiasmatic nucleus, a tiny clock in your hypothalamus, and set mainly by light. Keeping it steady supports your heart, metabolism, immune system, and thinking. Chronic disruption does the opposite. It is linked to obesity, type 2 diabetes, and faster biological aging.

## Sources

- Konopka RJ, Benzer S. (1971). Clock Mutants of Drosophila melanogaster. Proceedings of the National Academy of Sciences USA. https://doi.org/10.1073/pnas.68.9.2112
- Fagiani F, Di Marino D, Romagnoli A, Travelli C, Voltan D, Di Cesare Mannelli L, Racchi M, Govoni S, Lanni C. (2022). Molecular regulations of circadian rhythm and implications for physiology and diseases. Signal Transduction and Targeted Therapy. https://doi.org/10.1038/s41392-022-00899-y

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_Canonical: https://longevity-switzerland.com/en/glossary/circadian-rhythm · Part of Longevity Cities · Updated 2026-06-22_