Types of vitamin D found to have differing impact(s) on human health
New research investigating the effects of vitamin D supplementation on human health suggests slight differences – vitamin D3 may be more effective at strengthening the immune system and raising blood levels of vitamin D, compared to vitamin D2, researchers at the University of Surrey, UK, said.
In contrast, some study participants – out of several hundred – taking vitamin D2 were noticed to have lower levels of circulating vitamin D, leading the researchers to hypothesise vitamin D2 may have the potential to deplete or counteract beneficial effects of vitamin D3.
The study participants were enrolled in a placebo-controlled trial for 12 weeks and were otherwise healthy.
After 12 weeks, the researchers detected significant differences in gene expression between the vitamin D2 and vitamin D3 groups, “Notably, following vitamin D3 supplementation, the majority of changes in gene expression reflected a down-regulation in the activity of genes, many encoding pathways of the innate and adaptive immune systems, potentially shifting the immune system to a more tolerogenic status,” the researchers said.
“Surprisingly, gene expression associated with type I and type II interferon activity, critical to the innate response to bacterial and viral infections, differed following supplementation with either vitamin D2 or vitamin D3, with only vitamin D3 having a stimulatory effect.”
Speaking on the research, Professor Colin Smith, from the University of Surrey, opines that vitamin D3 may be more effective than vitamin D2 at strengthening immune responses against viruses. Vitamin D supplementation prior to any viral exposure is thought to be beneficial as it is unlikely there is clinical benefit in vitamin D supplementation after a viral infection takes hold.
Professor Susan Lanham-New, Head of the Department of Nutritional Sciences at the University of Surrey, meanwhile suggests vitamin D3 should be the preferred form of vitamin D supplement for most people.
Vitamin D is available in two main forms: ergocalciferol (vitamin D2) and cholecalciferol (vitamin D3). Prior research has established vitamin D3 supplements are much more effective at raising blood levels of vitamin D. It remains unclear if there is/are any functional differences to human health between the two types of vitamin D supplements.