The Claim

In primary human skeletal muscle myotubes, treatment with 100 nM of active vitamin D (1,25(OH)2D) for 5 days enhances protein synthesis signaling in the presence of insulin.

Source: Effects of vitamin D on primary human skeletal muscle cell proliferation, differentiation, protein synthesis and bioenergetics.

What the research says

Roughly balanced

Support and challenge are close. The picture may shift as more studies come in.

Supports
3score
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

When muscle cells from humans are treated with a specific form of vitamin D for five days, they become more active in building proteins — especially when insulin is also around.

See the scientific wording

In primary human skeletal muscle myotubes, treatment with 100 nM of active vitamin D (1,25(OH)2D) for 5 days enhances protein synthesis signaling in the presence of insulin.

What the research says

1 study

  1. Study: Effects of vitamin D on primary human skeletal muscle cell proliferation, differentiation, protein synthesis and bioenergetics.

    Scientists gave human muscle cells the active form of vitamin D for five days along with insulin, and found that the cells showed stronger signals for building protein — exactly what the claim said would happen.

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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