Protective Bioflavonoid. Suitable for Vegetarians. Gluten Wheat and Dairy Free. Kosher. Rutin is an important non-citrus antioxidant bioflavonoid. Flavonoids are a group of water-soluble plant pigments found naturally in many foods. They help your body to absorb and utilize Vitamin C. The natural source of Rutin in this formulation helps the body to fight free radicals which damage cells through oxidation.