Sep 22, 2025 02:29 AM
(This post was last modified: Sep 22, 2025 02:39 AM by C C.)
Common vitamin D supplements could reduce body’s best form of vitamin D, study warns
https://knowridge.com/2025/09/common-vit...udy-warns/
INTRO: Many people take vitamin D supplements to keep their bones strong and their immune system healthy, especially during the darker winter months when sunlight is scarce. But new research suggests that not all vitamin D supplements are equally effective—and one type may even lower the levels of the form our bodies use most efficiently.
The study, led by scientists at the University of Surrey, the John Innes Center, and the Quadram Institute Bioscience, examined the effects of two different types of vitamin D: vitamin D2 and vitamin D3. Both are available as supplements, and both can raise overall vitamin D levels, but the researchers found that vitamin D2 has an unexpected downside.
When people took vitamin D2 supplements, their blood levels of vitamin D3 dropped. Vitamin D3 is the form that our bodies naturally produce when skin is exposed to sunlight, and it is considered the most effective for boosting vitamin D status.
In many of the trials analyzed, participants taking vitamin D2 actually ended up with lower vitamin D3 levels than those who did not take any supplement at all. The findings, published in Nutrition Reviews, highlight the importance of understanding the differences between the two forms... (MORE - details)
https://knowridge.com/2025/09/common-vit...udy-warns/
INTRO: Many people take vitamin D supplements to keep their bones strong and their immune system healthy, especially during the darker winter months when sunlight is scarce. But new research suggests that not all vitamin D supplements are equally effective—and one type may even lower the levels of the form our bodies use most efficiently.
The study, led by scientists at the University of Surrey, the John Innes Center, and the Quadram Institute Bioscience, examined the effects of two different types of vitamin D: vitamin D2 and vitamin D3. Both are available as supplements, and both can raise overall vitamin D levels, but the researchers found that vitamin D2 has an unexpected downside.
When people took vitamin D2 supplements, their blood levels of vitamin D3 dropped. Vitamin D3 is the form that our bodies naturally produce when skin is exposed to sunlight, and it is considered the most effective for boosting vitamin D status.
In many of the trials analyzed, participants taking vitamin D2 actually ended up with lower vitamin D3 levels than those who did not take any supplement at all. The findings, published in Nutrition Reviews, highlight the importance of understanding the differences between the two forms... (MORE - details)