Brief
Study finds vitamin D2 supplements may lower vitamin D3 levels
University of Surrey researchers say vitamin D3 supplements are generally more effective than D2 at raising total vitamin D.
By Felo News Desk · Published
Research published last year in the journal Nutrition Reviews indicates that vitamin D2 supplements can decrease blood levels of vitamin D3, the form the body naturally produces, according to a University of Surrey study.
What the study examined
The team, led by Emily Brown, a PhD research fellow in the university’s Nutrition, Exercise, Chronobiology & Sleep Discipline, reviewed 11 randomized trials that measured participants’ vitamin D3 concentrations after starting vitamin D2 supplementation.
Key findings
Across the trials, participants taking vitamin D2 showed consistent reductions in vitamin D3 compared with control groups not taking D2. The researchers note that while D2 still raises overall vitamin D levels, D3 supplementation is more effective at increasing total vitamin D and may better stimulate immune defenses.
Expert comment
“This study suggests that subject to personal considerations, vitamin D3 supplements may be more beneficial for most individuals over vitamin D2,” the lead author said in a university statement shared via ScienceDaily.
Context
Vitamin D is essential for bone health, immunity and nutrient absorption. With reduced sunlight in winter, many turn to supplements. Earlier Felo coverage noted that 48% of adults under 30 take vitamins or minerals, highlighting growing supplement use (see related report).
Key facts
- Vitamin D2 supplements can lower blood levels of vitamin D3 (gizmodo.com)
- The study reviewed 11 randomized trials tracking D3 after D2 supplementation (gizmodo.com)
- Researchers recommend D3 supplements for most people needing to raise vitamin D (gizmodo.com)
Sources
- [1] gizmodo.com — originally reported as “Vitamin D2 Supplements Have a Surprising Drawback. Here’s What to Take Instead”
