Nature's Answer Immune Boost Herbal Blend Fluid Extract simply boosts the immune system naturally. Immune Boost includes a variety of herbs including Echinacea (Echinacea angustifolia, purpurea), Olive Leaf (Olea Europaea), Wild Indigo (Baptisia tentoria), Thuja (Thuja occidentalis) which are all well known for their immune supportive properties. Echinacea is well researched immune support herb, Olive Leaf and all other herbs are well known for its immune support properties. The alcohol free extracts are produced using cold Bio-Chelated proprietary extraction process, yielding a Holistically Balanced Advanced Botanical Fingerprint extract in the same synergistic ratio as in the plant.