Swanson® Resveratrol 100 mg is a food supplement designed to supplement the daily diet of adults. Each gelatin-coated capsule contains 100 mg of resveratrol obtained from Japanese knotweed root extract ( Polygonum cuspidatum ). What is resveratrol? Resveratrol is an organic plant-derived substance that is attracting increasing interest as a dietary supplement ingredient that can be used to supplement the daily menu of healthy people. The source of this compound in a properly balanced diet can be primarily berries such as strawberries, blueberries, black currants and walnuts or tomato skins, which are underestimated by some. Swanson ® brand also uses a natural source of resveratrol, which is the root of a plant called Japanese knotweed. Swanson® Resveratrol 100mg is just 1 capsule a day. A pack of 30 will provide one month of daily supplementation with naturally occurring resveratrol.