CHICAGO – Herbal remedies have been used to treat illness and promote health for thousands of years – and that’s enough evidence for some people during cold and flu season.
Peggy Everist, a 44-year-old elementary school teacher from Kansas City, takes Airborne, an effervescent tablet containing Chinese herbs, vitamins and echinacea, when she feels a cold coming on.
“It really seems to knock out the cold or at least make it less severe,” Everist said.
But what is the scientific evidence for alternative cold and flu remedies, such as echinacea, ginseng and zinc? Dr. Ronald B. Turner, a cold virus expert at the University of Virginia School of Medicine in Charlottesville, says the evidence is weak. But Turner doesn’t try to discourage people from spending their money on remedies they think make them feel better, as long as there are no harmful side effects.
“One of the things that permits people to believe in unproven therapies is that it really doesn’t matter what you take because you’re going to get better anyway,” Turner said.
Symptoms of the common cold increase rapidly and disappear just as fast, Turner said, making it difficult, but not impossible, for scientists to design studies proving what works.
But some studies have been done. Here is a quick look at the evidence.
Echinacea: The herbal supplement is made from purple coneflower. Early studies suggested some benefit, but more recent studies with better designs have found no effect on preventing colds or lessening their length or severity. There are no known significant side effects, but commercial products aren’t standardized. One study found that about half the echinacea products didn’t contain the species listed on the label.
Zinc: An essential mineral, zinc is found in oysters, beans, nuts and seeds. Studies have yielded mixed results. Those studies that showed zinc to be a successful cold fighter may be because subjects could taste the metallic flavor and believed they were getting the real thing rather than a dummy pill, so they reported they felt better. There are scattered reports of damage to the sense of smell from zinc nasal sprays. High daily doses (80 mg) have been linked to urinary problems. You can buy zinc in a variety of forms – nasal sprays, lollipops, gum, and lozenges, including Cold-Eeze lozenges.
Vitamin C: Found in fruits and vegetables, the nutrient got a huge boost to its reputation for cold prevention in 1970 when Nobel Prize-winning scientist Linus Pauling wrote a book endorsing it. Some studies have shown it reduces the duration and severity of colds when taken daily in doses of 200 mg or more. Other studies found nothing. Turner thinks there’s “probably little true effect.” Vitamin C can cause gastrointestinal problems in high doses.
Ginseng: Traditional Chinese medicine uses the extract of this root to restore energy. The commercial herbal supplement Cold-fX contains ginseng. Some studies have found ginseng lessens number and severity of colds. Turner says the studies were poorly designed. Another study found that most ginseng products contained less than half of what was listed on the label. Ginseng may cause insomnia.
Oscillococcinum: This homeopathic medicine, made from minuscule amounts of duck hearts and livers, is used to treat influenza. Studies have not produced strong evidence that it works. But New York Times personal health columnist Jane Brody has said she keeps it in her medicine cabinet, adding that it may be the belief in homeopathic medicine that make them work for some people.
Airborne: Growing in popularity, the brand-name herbal product Airborne is now the second highest selling cold tablet, with sales up 24 percent last quarter over the same period last year, according to Information Resources Inc., a company that tracks retail sales. But there are “no credible clinical studies, so no evidence of effect,” Turner said. “Based on the ingredients, (there is) no reason to expect an effect.”
Chicken soup: Also known as “Jewish penicillin,” chicken soup has been a favorite remedy for centuries. Some studies suggest its vapors warm up the respiratory passages and loosen mucus. An article in a magazine for nurse practitioners pointed out that chicken soup’s ingredients are known antioxidants and it keeps patients hydrated. Known side effects include feelings of comfort and nostalgia.