Every cell in your body uses CoQ10 to produce energy for cell maintenance and growth.  It is essential for the basic function of all cells.   It also acts as an antioxidant to help protect the body from free radicals.  CoQ10 levels decrease with age, the use of certain types of medications, and are seen to be low in individuals suffering with chronic diseases (Heart disease, Cancer, diabetes, etc).  CoQ10 levels in the body can be increased through supplementation.