“…Several studies demonstrated associations between levels of vitamin D and incerased risk of development of DM2 (Lu et al, 2018;Spiro and Buttriss, 2014). Vitamin D supplementation, resulting in changes of its levels, results in significant decrease of risk of DM2 (Zavorkova et al, 2018;Luo et al, 2015). Numerous studies found deficits in vitamin D levels not only in European countries, but worldwide (Tessari and Lante, 2017).…”