This chapter discusses the relationship between vitamin D and depression,
shedding light on the physiological functions of the unique characteristics of vitamin D,
its synthesis, and its role in extraskeletal activities apart from its established function in
bone metabolism. It further delves into the global prevalence of vitamin D deficiency
and the rising incidence of depression worldwide. The link between vitamin D and
depression is presented emphasizing the potential roles of vitamin D in neuromuscular
and immune function. The document also discusses the purported mechanisms
underlying the relationship between vitamin D and depression, including
neuroinflammation, imbalance in calcium homeostasis, and deficiency in
neurotransmitters. Furthermore, the document presents a comprehensive review of the
existing literature on the topic, citing multiple studies and reviews to support the
discussed findings. It covers various aspects, including the molecular basis of vitamin
D, its impact on neurobehavioral health, and its association with depressive symptoms
across different age groups primarily fetal origins, children, adolescents, adults, and
older adults. Many studies suggest a possible connection between depression and
vitamin D insufficiency, but the exact nature of this relationship and whether the
supplementation of vitamin D could effectively treat depression remains ambiguous.
Given that the link between vitamin D and depression has attracted attention, further
well-designed trials are needed to establish causality, elucidate the practical
consequences, and address the existing discrepancies and limitations in the evidence.
Keywords: Depression, Neuroinflammation, Neurotransmitters, Supplementation, Vitamin D insufficiency.
