Longevity & Aging · Metabolic & Cardiometabolic
periodic fasting-mimicking diet cycles decreases biological age composite clinical biomarker aging-clock score
In plain terms: Can monthly fasting-mimicking-diet cycles make you biologically younger?
A single small Longo-lab analysis reported about 2.5 years lower biological age, but biological-age clocks are a contested surrogate not a hard outcome and the deep sample was tiny (n=15) with no independent replication.
Evidence ladder
How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."
Top evidence so far: Human trials (RCT / n-of-1)
How the studies fall
The evidence (2)
| Source | Grade | Stance | Quality | Finding |
|---|---|---|---|---|
| Lean 2018 · Lancet | RCT | tested-null | high | Independent context: large diet RCTs demonstrate hard-endpoint change (diabetes remission) — the FMD claim rests on a soft surrogate (aging clock) not yet linked to morbidity/mortality outcomes in FMD trials. |
| Brandhorst 2024 · Nat Commun | RCT | supports | low | Human Longo-lab secondary analysis: 3 FMD cycles associated with about 2.5-yr lower biological age on a validated clock, independent of weight loss; exploratory, small deep-analysis subsample (about n=15), single group. |
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Educational only, not medical advice. Grades and scores reflect published evidence weighted by study design and quality; see the methodology.