Cholecalciferol and ergocalciferol compared for raising vitamin D levels in people
What it found
Across trials in adults, cholecalciferol raised blood vitamin D levels more than ergocalciferol.
The difference was clear with large single doses but not with daily ones.
What they found
Studies in people
Overall vitamin D levels
When all seven trials were combined, cholecalciferol produced a greater rise in blood vitamin D levels than ergocalciferol. This held true across different doses and delivery methods in these adult participants.
Large single doses
In three trials where people received one or a few large doses of 50,000 to 300,000 IU, cholecalciferol raised blood vitamin D levels much more than ergocalciferol did.
Daily doses
In six trials using daily doses of 1000 to 4000 IU, cholecalciferol appeared to raise levels slightly more than ergocalciferol. However, the difference between the two was not statistically significant.
How long levels last
Two trials showed that after a large dose, blood vitamin D levels from cholecalciferol stayed higher for longer. Levels from ergocalciferol fell back to baseline within 14 days in one trial, while cholecalciferol levels had not returned to baseline by 28 days.
Other findings
Why they differ
The authors explain that the two forms have slightly different chemical structures. Ergocalciferol has an extra methyl group on carbon 24. This means the body deactivates ergocalciferol faster, while cholecalciferol stays active longer.
What the authors conclude
- They conclude that cholecalciferol is better at raising blood vitamin D levels than ergocalciferol, so it could become the preferred supplement choice.
- They call for larger and stronger trials to explore why the two forms behave differently in the body.
- They say future research should look at how age, sex, ethnicity and genetics affect the way each form works.
How it was done
Scientists were unsure whether the two forms of vitamin D work equally well to raise blood vitamin D levels. They wanted to settle this because vitamin D is important for bone health and many people lack enough of it.
They gathered 10 randomised trials that directly compared cholecalciferol with ergocalciferol in adults. Seven trials had complete data for their main analysis, covering 1016 participants aged 18 to 97. The studies used different doses and lasted from 14 days to 12 months.
What it can’t tell you
- These trials only included adults, so the results may not apply to children or pregnant women.
- Most studies used doses far above what people normally get from food or sunlight.
- Scientists do not yet know if the same difference would happen at lower everyday doses.
Who paid
- Funding
- Funded by Medical Research Council; Department of Health; Biotechnology and Biological Sciences Research Council (from the PubMed record).
- Authors work at
- University of Surrey, UK
The paper
- Title
- Comparison of vitamin D2 and vitamin D3 supplementation in raising serum 25-hydroxyvitamin D status: a systematic review and meta-analysis
- Type
- Systematic review and meta-analysisThe authors follow a set, published method to find every relevant study, then combine the numbers from them into one result.
- Evidence
- Studies in people
- Summarised from
- Full text
- Cite
- Tripkovic L, Lambert H, Hart K, et al (2012). Comparison of vitamin D2 and vitamin D3 supplementation in raising serum 25-hydroxyvitamin D status: a systematic review and meta-analysis. The American journal of clinical nutrition. doi:10.3945/ajcn.111.031070Free full textPubMed 22552031DOI
Summary written 1 Oct 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error