Eating high potassium foods will change your energy in a short time. Potassium is not a stimulant. It is not a source of direct energy to the body. It is a mineral. Although a mineral, it is involved in many of the functions of the body and helps to maintain and improve those functions. It is involved in the function of the cell membranes of every cell in the body. The membranes of the brain cells, nerve cells, and muscle cells are heavily involved in how much energy we feel we have.