Thorne's Glutathione is NSF Certified for Sport®. It occurs naturally in cells and is a cofactor in dozens of enzymatic reactions involved in detoxification.* As an antioxidant, glutathione directly quenches several reactive oxygen species (free radicals).* The body’s benefits from maintaining a normal level of glutathione include support for liver function, pulmonary function, immune function, bowel health, carbohydrate metabolism, cardiovascular health, cognitive health, and eye health.* Glutathione-SR is a breakthrough in glutathione supplementation because its sustained-release formula protects it from stomach acid and digestive enzymes, allowing for a slower release and a more steady level in the bloodstream of this essential nutrient.*Glutathione is the most abundant anti-oxidant. Since training and competition create more oxidative stress and damage, athletes have a higher need for antioxidants. Exercise longer than 60-90 minutes significantly decreases glutathione levels in the blood, so supplementing is beneficial for endurance and ultra endurance events.The liver is the body’s largest reservoir for glutathione. A potent endogenous antioxidant, glutathione is essential for the liver’s phase I and phase II detoxification.* However, negative lifestyle issues and adverse conditions that affect liver health can result in a decreased amount of glutathione in the liver.Maintaining an optimal level of glutathione appears to be important for supporting cognitive function, especially during aging.* The normal process of aging is associated with a decrease in glutathione activity, which can result in increased oxidative activity.* Less than an optimum level of glutathione is observed in individuals experiencing a decline in cognitive function.* Conversely, individuals who live to 100 tend to have higher glutathione activity.*Although a common mistaken belief is that glutathione is not well absorbed when it's taken orally, significant data confirms that glutathione is efficiently absorbed across the intestinal epithelium by a specific uptake system.*Because athletes need to know their supplements are trustworthy and compliant, every batch of an NSF Certified for Sport® product is tested for compliance with label claims and to ensure the absence of more than 200 substances banned by many major athletic organizations.