What is Green Tea Extract? Swanson Green Tea Extract is a dietary supplement containing green tea leaf extract and powder. Each capsule is 550 mg of the valuable active ingredient in a gelatin shell. A standardized extract containing up to 60% polyphenols was used in the production of the preparation. Green tea has many properties, the most important of which are reducing the feeling of fatigue, beneficial effect on the immune system, supporting the cardiovascular system, antioxidant effects and support in weight loss, thanks to metabolic support. Green Tea Extract is a dietary supplement containing green tea extract and powdered leaves of green tea (Camellia sinensis (L.) Kuntze). Each capsule is 500 mg of the valuable active ingredient in a gelatin coating. Importantly, a standardized extract containing up to 60% polyphenols was used in the production of the preparation.