Plant extracts of Echinacea purpurea increase immune cell production during a viral cold infection and help make the suffering more bearable. Nutrition researchers at the Canadian University of Alberta conclude this from their tests on a commercial Echinacea preparation. The product manufacturer, Factors R & D Technologies, paid for the research.
The researchers carried out their study on 150 volunteers. The volunteers started to take the liquid Echinilin at the first sign of cold symptoms. On the first day, the subjects took eight doses of five millilitres each, and on the remaining days they took three doses. The volunteers did this for a week long.
For the first few days the cold symptoms became worse, and after that the Echinacea reduced the extremity of the symptoms. TDDS = total daily symptom scores; E = Echinacea; P = placebo.
From the blood samples taken from the test subjects, the researchers noticed that Echinacea increased the total number of immune cells. The neutrophils and monocytes increased in number, but the number of lymphocytes went down.
The immune cells started to behave differently in response to the supplement. At first Echinacea increased the amount of toxic substances that the neutrophils excreted, but this went down after a while. The figure below shows this effect.
3T = effect after two days; 8T = effect after seven days.
Echinacea probably induces the immune cells to produce more endogenous antioxidants, and this reduces the immune cells’ excretion of toxic compounds.
The researchers speculate that Echinacea stimulates the non-learning, primitive part of the immune system. This is the part of the immune system that is responsible for the first line of attack against intruders and ‘faulty’ cells. An indicator of this is the increase in symptoms in the early stages of the cold. As the cold progresses Echinacea inhibits ‘secondary infections’, the Canadians speculate.
Meta-studies have also shown the effectiveness of Echinacea. Taking Echinacea halves your chances of getting a cold. It appears that using it in combination with vitamin C works well. The active ingredients in Echinacea are alkamides, chlorogenic acid and polysaccharides, and we now know that alkamides interact with the CB2 receptor.
A proprietary extract from the echinacea plant (Echinacea purpurea) enhances systemic immune response during a common cold
In a previous paper, it was reported that Echinilin™ (Factors R & D Technologies, Burnaby, British Columbia, Canada) a formulation prepared from freshly harvested Echinacea purpurea plants and standardized on the basis of three known active components (alkamides, cichoric acid and polysaccharides) is effective for the treatment of a naturally acquired common cold. However, the mechanism by which this effect is achieved remains unknown. In the present study, Echinilin™ or placebo were administered to volunteers at the onset of their cold for a period of 7 days, with eight doses (5 mL/dose) on day 1 and three doses on subsequent days. Fasting blood samples were obtained before and during their colds. The decrease in total daily symptomatic score was more evident in the echinacea group than in the placebo group. These effects of echinacea were associated with a significant and sustained increase in the number of circulating total white blood cells, monocytes, neutrophils and NK cells. In the later part of the cold, the echinacea treatment suppressed the cold-related increase in superoxide production by the neutrophils. These results suggest that Echinilin™, by enhancing the non-specific immune response and eliciting free radical scavenging properties, may have led to a faster resolution of the cold symptoms. Copyright © 2005 John Wiley & Sons, Ltd.