According to new research Echinacea, a herbal remedy traditionally used to help fight infections does work and can in fact reduce the chances of catching a cold by more than half.
The research which looked at 14 different studies on the anti-cold properties of Echinacea, found that taking the product decreased the overall risk of catching a cold by 58% and the duration of the colds was reduced by an average of 1.4 days.
Nine species of Echinacea, also known as purple cornflower, are indigenous to North America and it was considered a potent medicine by Plains Indians.
It was also popular as a herbal remedy in both Europe and America in the 1930's.
The U.S. researchers, led by Dr Craig Coleman from the University of Connecticut School of Pharmacy, say they found that Echinacea has a benefit in decreasing the incidence and duration of the common cold.
However, they also say that further investigation is needed before the remedy could be recommended to patients; adverse side effects such as stomach upsets, nausea and dizziness have been reported with the use of Echinacea.
The three species most commonly used for their medicinal value are Echinacea angustifolia, pallida and purpurea and they are thought to boost the immune system and fight infection.
The U.S. scientists identified more than 800 products containing Echinacea and different parts of the plant, the flower, stem or root, were used in different products.
However exactly how the plant exerts its biological effects remains unknown and the study results do conflict with other studies that have shown no beneficial effect.
The research is published in the journal The Lancet.