Five carbon sugar mitochondrial support. D-Ribose is essential to life, and has been shown to support healthy cardiac function. It is an essential component of RNA and DNA. D- Ribose is a an essential ingredient in the production of ATP or energy. therefore it is needed for times of high energy output. D- Ribose improves stamina, athletic performance, strengthens cardio vascular system, increases cardiac muscle energy production and helps aid in atherosclerosis.