The Claim

In healthy older adults, modulation of thyroid status through either recombinant human TSH or oral T3 is associated with a 6–9% increase in insulin-like growth factor 1 (IGF-1) within 24 hours, indicating that elevation of thyroid hormone levels may stimulate IGF-1 production independently of growth hormone.

Source: Effect of Thyroid Status Modulation on Pituitary and Peripheral Hormone Concentrations in Healthy Older Subjects

What the research says

Supports is higher

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

Supports
40score
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

In older adults who are healthy, giving them thyroid hormones (either through a shot or a pill) can make a key growth-related protein called IGF-1 go up by 6–9% in just one day — and this might happen even if their growth hormone levels don’t change.

See the scientific wording

In healthy older adults, modulation of thyroid status via either recombinant human TSH or oral T3 is associated with a 6–9% increase in insulin-like growth factor 1 (IGF-1) within 24 hours, suggesting thyroid hormone elevation may stimulate IGF-1 production independently of growth hormone.

What the research says

1 study
  1. Study: Effect of Thyroid Status Modulation on Pituitary and Peripheral Hormone Concentrations in Healthy Older Subjects

    Scientists gave older adults either a TSH shot or T3 pills and found their IGF-1 levels went up by about 6–9% in a day or two — just like the claim said — without changing growth hormone, meaning thyroid hormones can boost IGF-1 on their own.

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

Fit Body Science verdict — we translate health claims into clear verdicts backed by peer-reviewed research.

Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.