In this paper, we looked into the effect vitamin D supplementation has on depressive symptoms in different populations. We found that, despite the existence of clear evidence towards the hypothesis, the number of solid studies (meat-analyses) on the topic were rather few and did not cover all populations. With this article, we aim to make it perfectly clear that there exists a need for far more research on the topic. At least 1 study showed that vitamin D had no effect on depressive symptoms, which also necessitates further research. Furthermore, nations, such as the republic of the Sudan, need to establish ?normal? vitamin D levels in their populations. This is also meant to urge such researches into taking place.