Home » The total number of essential vitamins required for the proper functioning of the human body is Vitamins MCQs The total number of essential vitamins required for the proper functioning of the human body is January 26, 2022 14 Views Q. The total number of essential vitamins required for the proper functioning of the human body is______________. A. 12 B. 13 C. 15 D. 22 Answer: 13.