The Claim

A three-day water-only fast reduces circulating insulin-like growth factor 1 (IGF-1) levels by approximately 30–40% in healthy adults and downregulates the mTOR pathway to promote cellular maintenance processes.

Source: Investigating the Impact of Glycogen-Depleting Exercise Combined with Prolonged Fasting on Autophagy and Cellular Health in Humans: A Randomised Controlled Crossover Trial

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
62score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

How it works
1 study reviewed
In plain English

A three-day water-only fast lowers IGF-1 levels by 30–40% in healthy adults, reduces mTOR pathway activity, and increases cellular maintenance processes.

See the scientific wording

A three-day water-only fast reduces circulating insulin-like growth factor 1 (IGF-1) levels by approximately 30–40% in healthy adults, which may downregulate the mTOR pathway and promote cellular maintenance processes.

Why this might work

When a person stops eating for three days, blood sugar and insulin drop, which causes the liver to stop producing a growth hormone called IGF-1. Lower IGF-1 tells cells to pause growth and start breaking down damaged parts. This shuts off a protein complex called mTORC1, which normally blocks cleanup. Once mTORC1 is off, cells build special containers that swallow broken components and deliver them to recycling centers, clearing out waste and renewing cellular function.

Verified mechanismbased on 1 study

What the research says

1 study
  1. Study: Investigating the Impact of Glycogen-Depleting Exercise Combined with Prolonged Fasting on Autophagy and Cellular Health in Humans: A Randomised Controlled Crossover Trial

    Going without food for three days lowers a hormone called IGF-1 by about one-third, which tells your cells to stop growing and start cleaning up damage — and this study proved it happens in healthy people.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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