Vitamin D2 (ergocalciferol), unlike D3 (cholecalciferol), ineffective for immune health

A very important study, with huge ramifications, considering most people taking prescription vitamin D are consuming vitamin D2 (ergocalciferol) as that is the only FDA-approved vitamin D variety available for oral use. The widely available OTC variety vitamin D3 (cholecalciferol) is not FDA-approved and doctors rarely prescribe it to their patients out of litigation fears. Well, according to the study below, when it comes to boosting immunity, people might as well throw their vitamin D2 pills/drops in the trash. Only viamin D3 was found to modulate a key biomarker of immune activity (type I interferon) responsible for the initial response to invading pathogens such as bacteria and/or viruses. Something tells me that the “active” vitamin D, known as calcitiriol, is also ineffective as immune booster…but I don’t want to rile up the vitamin D goblins attacking Danny and me lately:-)

https://doi.org/10.3389/fimmu.2022.790444

Study Finds Vitamin D3 Important for Fighting Infections – Helps Strengthen Defenses Against COVID-19

“…In a collaborative study by the Universities of Surrey and Brighton, researchers investigated the impact of vitamin D supplements – D2 and D3 – taken daily over a 12-week period on the activity of genes in people’s blood. Contrary to widely held views, the research team discovered that both types of vitamin D did not have the same effect. They found evidence that vitamin D3 had a modifying effect on the immune system that could fortify the body against viral and bacterial diseases. Professor Colin Smith, lead-author of the study from the University of Surrey, who began this work while at the University of Brighton, said:  “We have shown that vitamin D3 appears to stimulate the type I interferon signaling system in the body – a key part of the immune system that provides a first line of defence against bacteria and viruses. Thus, a healthy vitamin D3 status may help prevent viruses and bacteria from gaining a foothold in the body.“Our study suggests that it is important that people take a vitamin D3 supplement, or suitably fortified foods, especially in the winter months.”

“…Professor Susan Lanham-New, co-author of the study and Head of the Department of Nutritional Sciences at the University of Surrey, said: “While we found that vitamin D2 and vitamin D3 do not have the same effect on gene activity within humans, the lack of impact we found when looking at vitamin D2 means that a larger study is urgently required to clarify the differences in the effects. However, these results show that vitamin D3 should be the favoured form for fortified foods and supplements.””