Photo: Purple coneflowers, or echinacea, are on display at the Philadelphia Flower Show in this March 4, 2004 photo. With reported annual sales of more than $300 million, echinacea is one of the most popular medicinal herbs used by people to treat colds.

　　Being sick with a cold is nothing to sneeze at, but new research finds that taking the popular herbal remedy echinacea does nothing to treat or prevent it.

　　The federally funded study was what fans and foes of such substances say they have long needed — rigorous, scientific testing. It found that patients who took an echinacea plant extract fared no better than those who took a dummy treatment.