Abstract
Peak performances in different life domains are often achieved by healthy young- or middle-aged adults and are partly based on their executive functions. The extensive literature on older or non-healthy populations suggests an adequate availability of vitamin D as essential for good executive functioning. However, for healthy young- or middle-aged populations, the association between vitamin D levels and executive functions is not well understood. To test whether previous findings generalize to healthy young- or middle-aged participants, we conducted a scoping review to systematically map the existing literature on the association between vitamin D levels and executive functions. Literature searches of three databases were performed identifying seven studies that met the inclusion criteria. Results indicate mixed findings for the relationship between vitamin D and the three core executive functions cognitive flexibility, response inhibition, and working memory. Thus, this scoping review indicates a rather unsystematic impact of varying vitamin D levels or supplements on executive functions among healthy young- or middle-aged populations and we argue for more systematic investigations in the future.