Jarrow Formulas Quercetin is an immune system support supplement designed to enhance cardiovascular and immune system health.(1) These quercetin 500 mg capsules support immune function by providing quercetin, the bioflavonoid antioxidant found in onions, green leafy vegetables, and fruits such as apples and cherries.(1) Quercetin supports healthy cellular function, cardiovascular health, and has been shown to support a healthy immune response.(1) This support supplement is crafted to fit into various dietary routines as it is non-GMO and gluten-free. Adults are advised to take one capsule daily with meals or as instructed by a healthcare professional. Jarrow Formulas commits to blending superior science with smarter formulas to help you maintain optimal health through simple daily supplementation. (1) Jarrow Formulas – Superior Science. Smarter Formulas. (1)These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.