New evidence
High-dose vitamin D3 (24,000 IU every two weeks) raised sufficiency levels in just 46% of people with chronic spinal cord injury — even in a year-long trial.
This is some of the first rigorous evidence on vitamin D3 dosing for this specific clinical population, but 42 participants and a 46% success rate mean the results are far from a prescription for the general public — more before-and-after testing is needed before anyone assumes high doses guarantee sufficiency.
In a year-long, double-blind trial, people with chronic spinal cord injury were given either a placebo, 24,000 IU of vitamin D3 monthly, or 24,000 IU every two weeks. The every-two-week dose raised blood levels of vitamin D above the sufficiency threshold in fewer than half of the participants, with better results in those who had less severe injuries, lower body weight, or started with higher baseline levels. The study shows that even a high dose doesn't work the same for everyone in this group — and that individual factors matter a lot.
Where this fits in the evidence
This is among the first studies we've indexed on Vitamin D3 for Elevated Circulating 25-Hydroxyvitamin D Level — treat it as an early signal until more research accumulates.
The study
- Randomized Controlled Trial (RCT)
- n = 42
- 2025-01
- Topics in spinal cord injury rehabilitation
- PubMed: 41268138
- DOI: 10.46292/sci24-00077
- Full study breakdown →
This is a plain-language summary of a research finding, not medical advice. Pillser surfaces research signals to help you decide what's worth investigating — always consult a qualified professional before changing what you take.