Vitamins are organic compounds that are essential for various physiological functions in the human body. They are necessary for the proper functioning of various enzymes, hormones, and other molecules. There are 13 essential vitamins, each with its own specific functions and roles in the body. These vitamins are classified into two categories: fat-soluble vitamins (A, D, E, and K) and water-soluble vitamins (B vitamins and vitamin C). Research in the field of vitamins focuses on understanding their roles in maintaining overall health and preventing various diseases. This includes studying the effects of vitamin deficiencies, exploring potential health benefits of vitamin supplementation, and investigating the interactions between vitamins and other nutrients in the diet. Additionally, research is also conducted to determine optimal vitamin intake levels, identify populations at risk of vitamin deficiencies, and develop strategies for improving vitamin status in vulnerable groups.