Vitamin D absorption and effectiveness research

New research from British scientists, including researchers from the University of Surrey, John Innes Centre, and the Quadram Institute, suggests significant differences between Vitamin D2 (ergocalciferol) and Vitamin D3 (cholecalciferol). Findings published in Nutrition Reviews indicate that individuals taking Vitamin D2 supplements may experience lower blood concentrations of Vitamin D3 compared to those not using the supplement.

Vitamin D3, which is naturally produced in the skin via sunlight, is generally considered more effective at increasing overall Vitamin D levels. Additionally, studies in Frontiers in Immunology suggest Vitamin D3 may provide superior support for the immune system.

Dietary habits also impact Vitamin D efficacy. Because Vitamin D is fat-soluble, it is best absorbed when consumed with meals containing fats. Experts warn that taking supplements with black coffee or on an empty stomach may hinder absorption. Furthermore, while not directly blocking the vitamin, foods high in phytates—such as beans, lentils, and chickpeas—can interfere with the absorption of calcium, which works alongside Vitamin D to maintain bone health.