The Dark blue black berries of Sambucus migra L. have many naturally occurring nutritional substances such as Rutin, Quercertin (flavonoids) and Anthocyanins which support the immune system especially during the winter season or when experiencing extra stress. When deciding on a Sambucus liquid, remember to check the kind of sweetener it contains. Many brands add sugar or sorbitol while Nature's Answer® Sambucus contains only pure coconut glycerin.