Dr. Kristin Woodward tells us some natural ways to prevent the cold and flu.
Vitamin C may reduce the length of a cold but routine use does not prevent colds for most people. For most people, vitamin C does not prevent colds and only reduces their length and severity. It may be useful useful for people exposed to extreme physical stress, for example marathon runners. Vitamin C is generally considered safe. However in high doses can cause diarrhea, nausea, and abdominal cramps.
Geranium extract may be helpful in relieving symptoms of bronchitis and the common cold in adults but evidence is low and more research needs to be done. Geranium can be given in liquid drops three times a day. Research suggests geranium is generally well tolerated in most people.
Research generally supports the use of Echinacea by adults to prevent or treat a cold. However, additional trials are needed. In the lab, echinacea inhibits the production of pro-inflammatory cytokines induced by the flu virus and shows direct antiviral activity. There is substantial variability in echinacea products sold in the United States.
European black elderberry is widely used to treat colds and flu. In vitro, elderberry binds to and prevents infection with influenza H1N1 virus. Studies suggest that black elderberry extract (1-4 tablespoons daily for 3-5 days for adults) can inhibit the growth of influenza viruses in vitro and shorten the duration of flu symptoms. However, additional studies are needed to confirm these effects. No studies have demonstrated effectiveness of elderberry extracts in preventing or treating a cold. Elderberry is generally tolerated however allergic reactions are possible.
Studies suggest ginseng taken daily for 4 months can reduce the number and duration of colds in adults. In addition, 100 mg of ginseng a day 4 Weeks before and 8 Weeks after the flu shot may improve the effectiveness of the vaccine but more research is again needed before an overall recommendation can be made. Ginseng may cause hypertension and agitation.