One of the most popular claimed health benefits of elderberries is for cold and flu relief or prevention. However the fact of the matter is those claims are unproven, at least as of now. But what has been proven is that elderberries have a high ORAC value and therefore, contain a high amount of antioxidants.
ORAC Source
USDA Database for the Oxygen Radical Absorbance Capacity (ORAC) of Selected Foods, Release 2 - Prepared by Nutrient Data Laboratory, Beltsville Human Nutrition Research Center (BHNRC), Agricultural Research Service (ARS), U.S. Department of Agriculture (USDA) - May 2010