Healthy Origins - 100% Natural D-Ribose - 10.6 oz. 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 Healthy Origins 100% Natural D-Ribose may help replenish depressed levels of ATP, and improve workout recovery. Consider Healthy Origins™ 100 % Natural CoQ10 in combination with D-Ribose for enhanced cardiovascular support. Healthy Origins 100% Natural D-Ribose supports muscle recovery and cardiovascular health.