Non-GMO Natural Soy-Free Supports Muscle Recovery & Cardiovascular Health Bioenergy Ribose Dietary Supplement Suitable for Vegetarians and Vegans D-Ribose is a naturally occurring pentose (5-Carbon) sugar, which is a primary building block in the production of Adenosine Triphosphate (ATP) - the body's main energy source. ATP levels can become severely depressed following periods of rigorous exercise and metabolic stress. Supplementing with D-Ribose may help replenish depressed levels of ATP, and improve workout recovery. Consider Healthy Origins Natural CoQ10 or Ubiquinol in combination with D-Ribose for enhanced cardiovascular support.