Vitamins are the cofactors that act as a kind of catalyst for the hundreds of metabolic reactions that occur in your body. They are helper molecules which activate enzymes to work and assist in biochemical transformations.
These include antioxidants (vitamin A, C & E), B vitamins (for immune, heart and brain health and making energy), vitamin K (blood clotting & bone health) and vitamin D (bone & immune health)
Vitamin B12 and vitamin K can be made by gut bacteria in addition to obtaining these essential nutrients from the diet.