CoQ10 is a naturally occurring antioxidant found in every cell of our body, with particularly high concentrations in the heart, liver, and kidneys. Its primary role is to aid in the production of adenosine triphosphate (ATP), the molecule that supplies energy to our cells. As we age or if we have certain medical conditions, our body's natural production of CoQ10 can diminish, which may lead to decreased energy levels, muscle weakness, and a range of other health issues.