The Claim

In adults with prediabetes and serum vitamin D levels below 30 ng/mL, weekly supplementation with 60,000 IU of vitamin D3 for 12 weeks increases the oral glucose insulin sensitivity (OGIS) index by an average of 15.3 mL/min/m² compared to placebo.

Source: Effect of Vitamin D3 Supplementation on Insulin Sensitivity in Prediabetes With Hypovitaminosis D: A Randomized Placebo-Controlled Trial

What the research says

Supports is higher

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

Supports
77score
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.

Cause and effect
1 study reviewed
In plain English

In adults with prediabetes and low vitamin D levels, taking 60,000 IU of vitamin D3 weekly for 12 weeks increases insulin sensitivity by 15.3 mL/min/m² compared to a placebo.

See the scientific wording

In adults with prediabetes and serum vitamin D levels below 30 ng/mL, weekly supplementation with 60,000 IU of vitamin D3 for 12 weeks significantly improves insulin sensitivity, as measured by the oral glucose insulin sensitivity (OGIS) index, increasing it by an average of 15.3 mL/min/m² compared to placebo, suggesting vitamin D repletion may enhance glucose metabolism in this specific subgroup.

Why this might work

When vitamin D levels rise in the blood, it activates a receptor inside cells that turns on the gene for the insulin receptor. More insulin receptors are made on the surface of muscle and fat cells, allowing insulin to bind more effectively and pull sugar out of the blood, improving how well the body uses glucose.

Supported mechanismbased on 1 study

What the research says

1 study
  1. Study: Effect of Vitamin D3 Supplementation on Insulin Sensitivity in Prediabetes With Hypovitaminosis D: A Randomized Placebo-Controlled Trial

    In people with prediabetes and low vitamin D, taking a weekly high-dose vitamin D pill for three months helped their bodies respond better to sugar, as shown by a standard test called OGIS. The group taking vitamin D got significantly better at handling glucose than those who took a dummy pill.

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.