# Intermittent fasting

Intermittent fasting is an umbrella term for eating patterns that alternate normal eating with longer fasting windows. Common forms include 16:8 time-restricted eating, alternate-day fasting, and the 5:2 approach. During the fasting periods, your insulin and glycogen drop. That triggers three things. Your body burns fat (lipolysis). It makes ketones. And it ramps up autophagy (cellular recycling). Clinical trials show modest gains in body composition, blood-sugar control, and blood pressure. But here is the key finding. Meta-analyses suggest the results are broadly similar to simply cutting calories by the same amount. Some trials do report small edges for visceral fat or insulin sensitivity.

## Sources

- Longo VD, Mattson MP. (2014). Fasting: Molecular Mechanisms and Clinical Applications. Cell Metabolism. https://doi.org/10.1016/j.cmet.2013.12.008
- Trepanowski JF, Kroeger CM, Barnosky A, Klempel MC, Bhutani S, Hoddy KK, et al.. (2017). Effect of Alternate-Day Fasting on Weight Loss, Weight Maintenance, and Cardioprotection Among Metabolically Healthy Obese Adults. JAMA Internal Medicine. https://doi.org/10.1001/jamainternmed.2017.0936

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