The Claim

In healthy Korean men aged 19–40 years, serum IGFBP-3 levels exhibit a seasonal pattern with peak concentrations in autumn (mean 2,901 ng/mL) and lowest levels in winter (mean 1,563 ng/mL), and are moderately positively correlated with ambient temperature (r = 0.569), in contrast to the seasonal pattern observed for IGF-1.

Source: Serum IGF-1 and IGFBP-3 levels in healthy Korean men aged 19–40 years: a cross-sectional analysis of reference ranges and seasonal variation

What the research says

Supports is higher

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

Supports
44score
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.

Description
1 study reviewed
In plain English

In young Korean men, a protein in the blood called IGFBP-3 goes up in the fall and drops in the winter, and it seems to rise when it’s warmer outside — which is the opposite of how another related protein, IGF-1, behaves.

See the scientific wording

Serum IGFBP-3 levels in healthy Korean men aged 19–40 years peak in autumn (mean 2,901 ng/mL) and are lowest in winter (mean 1,563 ng/mL), showing a moderate positive correlation with ambient temperature (r = 0.569), indicating a distinct seasonal pattern opposite to that of IGF-1.

What the research says

1 study
  1. Study: Serum IGF-1 and IGFBP-3 levels in healthy Korean men aged 19–40 years: a cross-sectional analysis of reference ranges and seasonal variation

    This study found that a protein in the blood called IGFBP-3 goes up in autumn and drops in winter in young Korean men, just like the claim says — and it’s linked to how warm it is outside.

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

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