Vitamins A, D, E and K are fat-soluble, meaning that they dissolve in fat and are carried by fat molecules throughout the body. If we had no fat in our diets, we would be unable to absorb these vitamins and reap their benefits. These vitamins also can be stored in body fat, so taking supplements of fat-soluble vitamins-especially vitamin A or vitamin D-is risky unless prescribed by a doctor, since the stored excess can build up to dangerous levels.
The B-vitamins and vitamin C are water-soluble, which means that they dissolve in water and are carried throughout the body in the bloodstream. The body does not store most water-soluble vitamins with exception of vitamin B-12. Other than B-12, the body uses what it needs and the kidneys excrete any excess water-soluble vitamins in the urine.
Like vitamins, minerals are essential nutrients required to help the body function properly.