All berberine-containing herbs should be avoided during pregnancy because they may cause premature uterine contractions. It seems prudent to include garlic in the diet on a regular basis as a preventive measure and to increase its consumption, either fresh or in extract form, during cold and flu season. Other herbs are also reported to have either antimicrobial or immune-enhancing effects. All three have demonstrated virucidal activity in vitro. 38 People with high blood pressure, however, should consult a health care practitioner before using licorice.
Astragalus enhances T cell function.
39 Panax ginseng has been shown to increase numbers and activity of lymphocytes, neutrophils and T cells. 40 And shiitake, reishi and maitake mushrooms all contain polysaccharide and protein complexes that stimulate immune cells and their ability to produce antimicrobial substances. All of these medicinal plants can be taken alone or in combination with other immune-supportive supplements. Immune health is ultimately our last defense against disease-causing organisms. The antibiotics upon which we have grown so dependent do nothing to support our own resistance and in fact have created antibiotic-resistant organisms.