Research

Hormonal

Alternate day fasting for 3 weeks significantly increases skeletal muscle SIRT1 mRNA expression in nonobese humans, independent of sex.

Alternate day fasting increases SIRT1 gene expression in muscle, a marker associated with stress resistance and longevity in rodents. However, this study did not measure actual stress resistance or lifespan, so the practical health benefit remains uncertain.

ModerateSupportsMEDIUM confidence
alternate day fasting significantly increased expression of SIRT1 (Figure 2C; p < 0.01), independently of sex.
Leonie K. Heilbronn et al. · Obesity Research · 2005

Why this rating

Small sample size for biopsy (n=11), short duration, and reliance on mRNA rather than protein activity or functional stress tests.

Source

Glucose Tolerance and Skeletal Muscle Gene Expression in Response to Alternate Day Fasting

Leonie K. Heilbronn et al. · Obesity Research · 2005

DOI 10.1038/oby.2005.61

crossover · n=16Cited 174×
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DOI resolved against Crossref · corpus check 2026-06-10

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