NOW Pyruvate includes a stable, supplement-ready form form of pyruvic acid, a substance manufactured by the body to help produce the cellular energy factor ATP (adenosine triphosphate). ATP is the most important energy source for cells powering most vital functions. So increasing the amount of ATP available to a cell should theoretically increase or enhance its work capacity. Pyruvic acid can be synthesized by the body, but only at a limited rate. So people use pyruvate supplements like this one from NOW Foods to enhance exercise endurance and aid fat loss. As with all NOW Foods products, you can trust the purity and potency of these NOW Pyruvate tablets. Optimal dose is 5-6 grams per day.