The Claim

In female weanling Sprague-Dawley rats, higher dietary vitamin D3 intake (2–4 IU/g) is associated with greater lean mass accretion over an 8-week period compared to lower dietary vitamin D3 intake (1 IU/g), without significant changes in body weight or fat mass.

Source: Lean body mass accretion is elevated in response to dietary vitamin D: A dose-response study in female weanling rats.

What the research says

Supports is higher

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

Supports
14score
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.

Correlation
1 study reviewed
In plain English

When young female rats eat more vitamin D3 in their food, they grow more muscle over 8 weeks, but their overall weight and fat don’t change.

See the scientific wording

In female weanling Sprague-Dawley rats, higher dietary vitamin D3 intake (2–4 IU/g) is associated with greater lean mass accretion over 8 weeks compared to lower intake (1 IU/g), without changes in body weight or fat mass.

What the research says

1 study
  1. Study: Lean body mass accretion is elevated in response to dietary vitamin D: A dose-response study in female weanling rats.

    Rats that ate more vitamin D3 gained more muscle over 8 weeks without getting heavier or fatter, exactly what the claim says.

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.

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