Echinacea is an herbal remedy people often use to treat the common cold. Many people believe that the plant can boost the immune system and reduce the severity or length of colds. Echinacea is one of the best-selling herbal products in the U.S.
But despite its popularity, some recent studies of echinacea for the common cold have not found that it helps. If echinacea does have a benefit, many researchers feel that it has not been proven.
Mothers are celebrated (if sometimes vilified) for their eagerness to advise
their children on matters big and small: how to behave, what to wear, whom to
marry, when to have kids ... and, oh yes, how to stay healthy during cold and
Does science back up what Dr. Mom told you about the common cold? Or was she
full of hot air? Here's what real doctors have to say about 10 familiar
Echinacea is a flowering plant that grows throughout the U.S. and Canada. There are nine species. Some of the plant's common names are the purple coneflower or black-eyed Susan. The leaves, stems, flower, and roots may be used to produce supplements, liquid extracts, and teas. People have used echinacea as a remedy in the Americas for centuries.
Echinacea for the Common Cold: Does It Work?
Studies of echinacea for the common cold have had mixed results. Extracts of echinacea do seem to have an effect on the immune system. Studies have shown that it increases the number of white blood cells and boosts the activity of other immune cells.
But these effects may not translate into an actual benefit when it comes to fighting the common cold. A study published in 2005 in the New England Journal of Medicine found that echinacea was no more effective than a placebo in preventing colds. It also did not reduce the severity of cold symptoms.
Two studies funded by the National Center for Complementary and Alternative Medicine also did not find any benefit from echinacea for the common cold in either children or adults.
However, there are many variables in studying echinacea for the common cold. Studies have looked at different types and strengths of echinacea as well as different parts of the plant or root. This makes it hard to compare the results. It's possible that some formulations are better than others. Echinacea may also help against some viruses that cause colds but not others.