Natural Factors C Extra + Quercetin - An immune-support formula that combines the antioxidant benefits of vitamin C with the bioflavonoid quercetin for enhanced support. Vitamin C is not stored by the body and needs to be consumed daily in order to maintain the levels recommended for overall health. Vitamin C is an essential nutrient that helps in collagen formation, which is needed for the normal development and maintenance of bones, cartilage, teeth, and gums. It also helps maintain the body’s ability to metabolize nutrients. Quercetin is a bioflavonoid found in many fruits, vegetables, and herbs. It has a wide range of benefits, including allergy relief, cardiovascular support, and enhancing the body’s absorption and use of vitamin C. Both vitamin C and quercetin also help protect tissues from free radical damage. C Extra + Quercetin contains 500 mg of Vitamin C blended with 250 mg of Quercetin for anyone looking for additional immune and antioxidant support.