The role of vitamin D in the human body is not only participation in the regulation of calcium and phosphate metabolism, prevention of rickets in children or osteomalacia and osteoporosis in adults. Vitamin D deficiency can be caused by a variety of health conditions. Currently, epidemiological studies confirm the relationship between vitamin D deficiency in the body and an increased risk of neurodegenerative diseases, psychiatric disorders, autoimmune diseases and in cancer prevention. Vitamin D deficiency has been identified as a common metabolic abnormality. Despite known dietary sources of vitamin D and the role of sunlight in its production, a significant proportion of the population may have insufficient serum levels of 25-hydroxyvitamin D.