Healthvit Resveratrol 100MG Calcium | 60 Capsules Resveratrol is a powerful antioxidant that is produced by some plants to protect against environmental stresses. Perhaps the most notable producer of resveratrol is the grapevine, which produces large amounts of resveratrol in the skins of grapes to protect against sun damage.Resveratrol is a powerful antioxidant that is produced by some plants to protect against environmental stresses. Perhaps the most notable producer of resveratrol is the grapevine, which produces large amounts of resveratrol in the skins of grapes to protect against fungal diseases and sun damage.It is therefore no surprise that wine ( In particular red wine – which is fermented with grape skins ) has some of the highest levels of resveratrol out of any natural food.