When it comes to immune support, quercetin alone is great. But quercetin combined with zinc and copper is even better.* The benefits of quercetin, a natural plant compound, are many.* It protects cells from damaging free radicals, helps regulate immune response, and supports sinus health.* This formula amplifies the benefits of quercetin with zinc, which is crucial for immune support, and copper, which competes with zinc for absorption.* Quercetin helps zinc enter cells, so it can better do its immune work.* Copper helps maintain the optimal zinc/copper ratio needed for all-around health.*