Research paper
Monthly high-dose vitamin D supplementation does not increase kidney stone risk or serum calcium: results from a randomized controlled trial.
Study answer
What this study found
Monthly 100,000 IU vitamin D3 did not increase kidney stone events or hypercalcemia compared with placebo over a median follow-up of 3.3 years. Kidney stone events occurred in 76 vitamin D participants versus 82 placebo participants, with HR 0.90 (95% CI: 0.66, 1.23; P = 0.51). Hospitalizations for urolithiasis were also not increased (7 vitamin D vs 11 placebo; HR 0.62, 95% CI: 0.24, 1.26; P = 0.30). In the annual blood-test subsample, there was no hypercalcemia in the vitamin D arm, and mean serum calcium rose from 2.28 at baseline to 2.36 at year 3 with no significant time-by-treatment…
- Study & population
- Population-based, double-blind, placebo-controlled randomized trial in adults aged 50-84 years living in Auckland, New Zealand.
- Intervention
- Monthly oral vitamin D3 100,000 IU was given as identical-looking soft-gel capsules containing sunflower oil, with 2 capsules in the first month and then 1 capsule monthly thereafter.
- Key limitation
- Hypercalcemia assessment was limited to an annual blood-test subsample, and calcium-related events were rare.
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Open PDFOriginal abstract
BACKGROUND A growing number of randomized controlled trials (RCTs) are investigating the potential health benefits of high-dose vitamin D supplementation. However, there are limited RCT data on the safety of calcium-related adverse effects. OBJECTIVE…