The Claim

In adults aged 40-85 years with a dietary calcium-to-magnesium intake ratio of at least 2.6, oral magnesium supplementation for 12 weeks increases plasma 25-hydroxyvitamin D2 (25(OH)D2) levels in a manner dependent on baseline 25-hydroxyvitamin D (25(OH)D), with a statistically significant 8.39-fold increase at baseline 25(OH)D of 50 ng/mL compared to placebo.

Source: Magnesium status and supplementation influence vitamin D status and metabolism: results from a randomized trial.

What the research says

Supports is higher

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

Supports
84score
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

For people aged 40 to 85 who eat a lot more calcium than magnesium, taking a magnesium pill for 12 weeks boosts their blood level of a specific form of vitamin D (vitamin D2). The boost is bigger when they already have more vitamin D at the start—up to 8 times higher compared to a sugar pill.

See the scientific wording

In adults aged 40-85 years with a dietary calcium-to-magnesium intake ratio ≥2.6, magnesium supplementation for 12 weeks increases plasma 25-hydroxyvitamin D2 (25(OH)D2) levels as baseline 25(OH)D increases, with a significant 8.39-fold increase at baseline 50 ng/mL compared to placebo. This effect was dose-dependent relative to baseline 25(OH)D.

Why this might work

When you take magnesium, it helps certain proteins in your liver and kidneys that process vitamin D. When your vitamin D level is already high, these proteins work better and break down one form of vitamin D (vitamin D3) more quickly, but they don't break down another form (vitamin D2) as fast. So vitamin D2 stays in your blood longer and its level goes up, especially if you start with high vitamin D.

Suggested mechanismbased on 1 study

What the research says

1 study

  1. Study: Magnesium status and supplementation influence vitamin D status and metabolism: results from a randomized trial.

    The study showed that taking magnesium pills can significantly increase the amount of vitamin D2 in your blood, especially when you already have high vitamin D levels. At a starting level of 50, vitamin D2 went up by more than 8 times.

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

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