You've likely heard about it in the mainstream media, but in case you didn't, a new study published in the most recent issue of the prestigious medical journal The Lancet Infectious Disease, supports the use of echinacea in the battle against the common cold.¹ A group of researchers from the University of Connecticut School of Pharmacy conducted a meta-analysis of 14 previous studies on echinacea. The researchers reviewed the studies for two criteria, incidence of the common cold and duration of the common cold. The analysis revealed that echinacea may reduce the risk of contracting a common cold by 58% and reduce the duration of a cold by 1.4 days.

While this may come as no surprise to those who have used echinacea in the past, this contradicts a much-publicized and much-criticized study which appeared in the New England Journal of Medicine (NEJM) in 2005 that found echinacea was not effective. At that time, critics pointed out that the NEJM-published study was fundamentally flawed because the researchers used a product devoid of phenolic compounds (which are believed to be the active components) and failed to administer adequate amounts to the test subjects.

The researchers of the new study also point out that echinacea is most effective when used periodically. Echinacea should not be used chronically, but rather periodically for up to two weeks at a time, followed by at least one week off.

1. Shah, S. A., S. Sander, et al. (2007). "Evaluation of echinacea for the prevention and treatment of the common cold: a meta-analysis." Lancet Infect Dis 7(7): 473-80.