Originating from the acidic swamps of North America, cranberries have been consumed fresh or dried for centuries by various Native American populations. A small berry highly valued for its taste, cranberries also contain numerous compounds, including proanthocyanidins (PAC), as well as a natural sugar: D-mannose. Each capsule contains 400 mg of high-quality cranberry powder combined with 60 mg of vitamin C. Vitamin C contributes to the normal functioning of the immune system.