This is an example of how I break down some of the research around the most common herbs used in many cold and flu remedies:
🌱 Astragalus: In-vitro, in-vivo, and clinical studies have demonstrated some immune-stimulating effects. Many of the clinical studies (“clinical” = human studies) studied in populations of immunodeficient or immunocompromised individuals show increased natural killer cell activity compared to their control (no treatment) groups. Interestingly, most of the clinical studies were done in cancer populations due to the inherent immunosuppressive property of cancer cells. In this population of patients, astragalus improved their immune markers and also seemed to improve their quality of life.
🌱 Ginseng: Clinical studies show that the immunomodulating properities of ginsenosides may come from an up regulation of phagocytic activity of mononuclear cells and increased T-cell and natural killer cell activity. In terms of reducing frequency of colds, there is data that supports the use of ginseng to reduce instances of the cold & flu compared not taking anything.
🌱 Echinacea: Despite the wide use of this herb in many “cold remedies”, most of the data to support its use isn’t actually that strong. Many pre-clinical (“pre-clinical” = nonhuman) trials definitely show some immunomodulatory effects including up regulation of immune cells (phagocytes, natural killer cells), but there aren’t many clinical trials that demonstrate that there is any reduction to the frequency, duration, or severity of colds.
So, what does this ALL mean? To me, not only is it important that preclinical data demonstrates some sort of physiological benefit, but it has to MATTER. Does it decrease the severity of the illness? Does it reduce frequencies of colds & flus? These are important answers that I look for in the literature before I make any recommendations to my patients.
**Check with a healthcare professional before consuming any natural health product
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