Selective Science And Low Dose Echinacea Studies

A study published in the New England Journal of Medicine in July 2005 which found that echinacea was not effective against the common cold, has indeed affected sales of echinacea - and public perception - in some quarters. In the UK, for example, sales dropped from a high of 6.1 million euros to 4.9 million in 2005. This is unfortunate, as the study has been roundly criticised in a number of areas.

There are 3 basic areas that been called into question within the study:

1. the dosage
2. the type of echinacea product used
3. the relevance of artificially inducing a virus in young and healthy volunteers

The dosage of echinacea used is one of the most critical points. Even assuming the quality of echinacea extract used in the study was the same as that used by good commercial preparations, the study participants were given about one third of the recommended dosage for those suffering a cold.

Sick college students in the study were only given 1.5 ml extracts of echinacea, three times a day. In milligrams, the 1.5ml was approximately equivalent to 300mg of the dried powdered root, or 900 mg of echinacea in total per day. Compare this to the dosage recommended by the World Health Organization (WHO), which is 3 grams per day of the dried root. So, the World Health Organization recommends 330% MORE echinacea per day for cold and flu symptoms. As Michael McGuffin, of the American Herbal Products Association, said: "It's like conducting a study on the effect of a third of an aspirin and wondering why you still got a headache."

The headache continues for good science. Looking at the type of echinacea extract used in the study, there are further discrepancies when compared with commercial preparations.

The study used extracts that were made in a university lab. If there was a standard method to extracting echinacea so that all of the active ingredients were present in the same quantities, this would not be a problem. However, this is just not the case. MediHerb, who make herbal preparations under the guidelines of pharmaceutical Good Manufacturing Practices, wrote that after testing other commercial echinacea products worldwide, they could not find one that had anywhere near the level of alkylamides that their strongest echinacea product did. Echinacea alkylamides are an important active constituent responsible for immune stimulation.

It is significant that even amongst commercial products - made by companies with a vested interest in getting echinacea extracts right - there is such a variance in quality. Even Consumer Lab, an independent testing organization, noticed quite a variance in different commercial preparations. They were testing for phenols, not alkylamides, though.

But what hope is there that one study lab, inexperienced in making echinacea, was able to produce the quality that many commercial preparations failed to deliver? In any case, unless the study co-ordinators provide a chemical profile of the echinacea they made, any comparisons to commercial products are without scientific foundation.

One of the study authors, David Gangemi, even said this about the dosage and the extract they used: "I think in retrospect if we go back and we look at some of the other products that are out there maybe we're only one tenth the level we should be."

The final point that has been raised about the study is just how relevant it is to compare the experience of healthy college students, with a good immune system, to the typical consumer of echinacea supplements. As one herbalist said, it is difficult to generalize their experience: "This could be irrelevant to the real life situation where people with compromised immunity are exposed to a range of constantly evolving viruses and bacteria."

There are a lot of studies that have found echinacea does in fact help alleviate the symptoms of colds and flus, and help in the recovery process. The American Botanical Council provides summaries of 21 clinical trials on different echinacea preparations, and types of echinacea (there are 3 species) on their website. It's a shame that these successful trials did not receive the same media coverage that a flawed study did.

References:
1. American Botanical Council
2. MediHerb Clinical Support and the Standard Process website
3. Nutraingredients

If you'd like to learn more about echinacea, see these articles. Rebecca presents this herbal medicine information site.