Americans are turning to cold and flu supplements in greater numbers.
By R. Morgan Griffin
WebMD Feature Reviewed by Michael W. Smith, MD
This year, people in the U.S. will suffer up to 50 million cases of flu and about a billion colds. But while the misery of cold and flu season might be inevitable, one thing is changing: where we look for relief.
Research indicates that many of us are turning away from the over-the-counter medicines we grew up with and toward natural cold and flu remedies, like vitamin C, zinc, echinacea and others.
Last year we spent over $1.5 billion on supplements to boost immunity and help ward off colds and the flu.
The market for these supplements appears to be growing more than twice as fast as the market for over-the-counter cold and flu drugs.
Experts aren't surprised. "From a conventional medical standpoint, there's just not much that's effective for cold and flu," says David C. Leopold, MD, director of integrative medical education at the Scripps Center for Integrative Medicine in San Diego. "People are trying to find something else that will work."
The incentive may be particularly strong now, given recent FDA reports about the ineffectiveness -- and even risks -- of over-the-counter cold and flu treatments in children.
But do alternative treatments offer the relief that pharmaceutical companies can't? There's growing evidence to suggest that some might -- at least to a modest degree. WebMD turned to the experts to get the details.
Natural Cold and Flu Remedies: How Good Is the Evidence?
First things first: cold and flu viruses are not the same thing. While colds are a drag, flu is much worse.
The symptoms of flu are more severe; they include fever and body aches along with congestion.
Flu can be dangerous, too; flu kills over 30,000 people a year.
But because there's some overlap in symptoms, treatments are often lumped together.
How well do natural cold and flu remedies work? Paul M. Coates, PhD, director of the Office of Dietary Supplements at the
National Institutes of Health, says that possible benefits appear to be small. But that's a good thing, in a way.
"If a supplement has a big, positive effect, then we worry about an equally powerful negative effect," Coates tells WebMD. Experts agree that popular natural cold and flu remedies seem to be safe for the average person. That's important when dealing with unproven treatments. So long as there's little risk in trying a supplement, the evidence of a benefit doesn't need to be quite so strong.
Which Natural Cold and Flu Remedies Should You Consider?
To help guide you, here's a rundown of the most notable cold and flu supplements according to the experts. Note that some have been studied with colds, while others with flu.
Vitamin C for Colds
While vitamin C has been long used as a treatment for the common cold, you might be surprised at how conflicted the evidence is. While it seems to boost some aspects of the immune system, studies do not show that vitamin C -- at least in doses of 1 gram per day -- helps prevent colds in most people.
As a treatment, the evidence is somewhat better. Some studies show that vitamin C can reduce the duration of a cold by as much as 24 to 36 hours. However, other studies show that even very high doses -- 3 grams a day -- have no effect.
Keep in mind that the high doses of vitamin C sometimes recommended for cold and flu can upset the stomach. Leopold is particularly wary of using high doses of vitamin C in children.
Echinacea for Colds
Once again, the evidence is mixed. While some studies do not show that echinacea works as a treatment, others show it can reduce the length and severity of colds by 10% to 30%.
Despite the confusion, many experts are fairly sure that echinacea can help treat colds. Leopold points out that some of the conflicting study results may stem from researchers testing different species of echinacea. So far, the best evidence supports taking echinacea purpurea.
Can echinacea also help prevent you from catching cold or flu viruses? Most studies say no.
Echinacea does have some mild risks. If you have allergies to ragweed or certain flowers, don't take echinacea before talking to your doctor. It may also not be safe for people with certain diseases that affect immunity, such as autoimmune conditions like rheumatoid arthritis and lupus, Leopold says.
Zinc for Colds
Zinc lozenges have become a popular treatment for the common cold.
Laboratory studies show that zinc can fight the cold virus in a test tube. But it's not clear that zinc has the same affect on cold viruses in the human body. As a treatment, some studies show that lozenges with 9 to 24 milligrams of zinc can shorten the duration of a cold and ease symptoms. However, you need to start as soon as symptoms appear and take them every two to three hours (except when you're sleeping.) Other studies show no benefit.
Can zinc also help prevent colds or the flu? So far, there isn't good evidence to support zinc lozenges for cold and flu prevention.
Elderberry for the Flu
There's some promising evidence that elderberry might help treat the flu, Leopold says. Elderberry appears to boost the production of some immune cells, and may also help block a virus's ability to spread. One study shows that taking 4 tablespoons a day for three days of a specific formulation of elderberry extract -- Sambucol -- appears to shorten the symptoms of flu by 56%. It also seems to reduce some flu symptoms, like fever. However, the study was small and the full implications aren't clear.
Garlic for Colds and Immunity
Like a number of other supplements, garlic seems to stimulate the immune system. Garlic may also help fight viruses. Also, there is some preliminary evidence that garlic may lower the risk of catching a cold.
However, more research needs to be done. Note: Garlic may be dangerous in people taking blood thinners.
Ginseng for Cold and Flu
While commonly used as a mild stimulant, ginseng may also boost the immune system and help prevent or treat cold and flu. One species, panax ginseng, may also increase the protection offered by the flu vaccine.
Coates singles out a specific blend of North American ginseng sold as Cold fX. Preliminary results suggest that Cold fX, when taken for several months during flu season, seems to lower the risk of contracting either cold or flu. As a treatment, it also seems to reduce the duration and the severity of the symptoms. "The jury's still out, but the evidence is promising," says Coates.
Andrographis for Colds and Immunity
"Andrographis is called 'Indian echinacea,'" says Evangeline Lausier, MD, assistant clinical professor at Duke Integrative Medicine in Durham, N.C. "It seems to stimulate the immune system." Studies of andrographis show that it appears to improve cold symptoms significantly, at least when started within three days of the onset. There's also some early evidence that it may reduce the chances of catching a cold, at least when taken for several months beforehand. Most studies have used a specific product called Kan Jang, which combines andrographis with eleutherococcus senticosus.
Combination Supplements for Colds and Flu
Many alternative medicines packaged for cold and flu are combinations of some of the herbs and vitamins listed above -- typically echinacea, zinc, high doses of vitamin C, and other ingredients. While there's no particular reason to think that combination cold and flu products are more dangerous, they're much less likely to have been studied than the individual ingredients that they contain. You might be better off choosing the specific supplements in the dosages you want.
These aren't the only supplements sold as natural cold and flu remedies. Others include astragalus, goldenseal, kiwi, and boneset. However, so far, there's not enough evidence to say whether they help with cold or flu.
Natural Cold and Flu Remedies: What Are the Risks?
Experts say that natural cold and flu remedies seem fairly safe -- at least when taken in normal doses by healthy adults. The fact that you'd probably only use them for a few days when you're sick adds to their safety.
"The risks of potentially toxic effects from herbs are almost always related to long-term use," says Paul R. Thomas, EdD, RD, scientific consultant for the Office of Dietary Supplements at the National Institutes of Health.
There are some exceptions. Talk to your doctor before taking any herb, supplement or vitamin if:
You are pregnant.
You have a medical condition.
You take medicines or other supplements, which may interact to cause problems.
Make sure you purchase brands of supplements that bear a USP or NF seal on the label. The USP and NF seals indicate the supplements have undergone quality-control testing.
Also, don't rely on supplements when you truly need medical care.
"I think the biggest risk is when the symptoms don't subside, but people just keep trying to treat themselves with supplements instead of seeing a doctor," Leopold tells WebMD. Self-treatment is especially risky when it comes to the flu. Influenza can be dangerous, especially to those who are very young, older, or sick.
Natural Cold and Flu Remedies in Children
Are natural cold and flu remedies safe for kids? It's a question many parents are asking, particularly in light of the risks of cold and cough medicines for children.
Leopold believes that using supplements in children can be a reasonable option -- provided you always check with a pediatrician first. Keep in mind that most alternative supplements have never been studied in children specifically. So we can't be certain that a treatment that is effective and safe in adults will work the same way in kids.
Always err on the side of caution. "When a child is really sick, you don't want to waste time messing with herbal stuff," says Lausier. "You need to get them to a pediatrician."
Cold and Flu: Other Natural Treatments
Natural remedies for colds and flu go well beyond herbs and supplements. Good lifestyle and hygiene habits are proven to reduce your risk of getting sick.
Eat healthy foods. Get regular exercise. Learn to manage stress. Those are among the best natural ways to prevent colds and flu, says Leopold.
Cover your mouth when you cough. Make sure to cough into your sleeve instead of your hand, Lausier says. You'll reduce the odds of passing your germs onto someone else.
Wash your hands. Washing with soap -- or rubbing your hands with an alcohol-based gel -- remains one of the best ways of protecting yourself from cold and flu germs.
Don't Forget to Get the Flu Vaccine
Nowadays, an annual flu vaccine is recommended for most children and adults. It's highly effective and, contrary to what you may have heard, the flu vaccine cannot give you the flu. It can save you and your family a lot of misery.
