Natural Factors Quercetin with Zinc & Copper - A potent antioxidant supplement that protects against oxidative stress and is used in herbal medicine as a capillary and blood vessel protectant. Quercetin is a bioflavonoid found in many vegetables, fruits, and herbs. Increased intake helps support cellular health throughout the body by counteracting unstable free radicals, provides seasonal allergy relief, and may support immune health. Natural Factors Quercetin is a great choice for anyone who wants to take a plant-based approach to self-protection and is a key addition to any health defence toolkit.